taxonomic revision of genus gyretes brullé (coleoptera: gyrinidae) from america north of mexico

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Taxonomic Revision of Genus Gyretes Brullé(Coleoptera: Gyrinidae) from America North ofMexicoAuthor(s): Jennifer Babin and Yves AlarieSource: The Coleopterists Bulletin, 58(4):538-567. 2004.Published By: The Coleopterists SocietyDOI: http://dx.doi.org/10.1649/677URL: http://www.bioone.org/doi/full/10.1649/677

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TAXONOMIC REVISION OF GENUS GYRETES BRULL�

(COLEOPTERA: GYRINIDAE) FROM AMERICA NORTH OF MEXICO

JENNIFER BABIN AND YVES ALARIE1

Department of Biology, Laurentian University,Ramsey Lake Road, Sudbury, Ontario P3E 2C6, CANADA

Abstract

Species of the genus Gyretes Brulle of America north of Mexico are reviewed. Morphologicalvariation among species is characterized using multivariate analyses. Three species are recognized:Gyretes iricolor Young, G. sinuatus LeConte and G. torosus new species. Gyretes compressusLeConte and G. californicus Regimbart are synonymized under G. sinuatus new synonymies.Diagnoses, illustrations, and a key to identify species from America north of Mexico are provided.

The aquatic beetle family Gyrinidae comprises four genera in America north ofMexico; Gyrinus Muller (41 species), Dineutus MacLeay (11 species), Gyretes Brulle(3 species) and Spanglerogyrus Folkerts (1 species) (Roughley 2001). Of these,Gyretes is the least studied. Adults of this genus are stream-dwellers that can bedistinguished from other North American gyrinids by the hidden scutellum, the conicalshape of the last abdominal segment and the presence of pubescence along the marginof the pronotum and elytra (Ferkinhoff and Gundersen 1983; Oygur and Wolfe 1991).Specimens of Gyretes generally are found in areas shaded by overhanging banks andvegetation. Individuals frequently leave the flowing water to rest by climbing ontoemergent roots and leaves (Folkerts and Donavan 1973; Steiner and Anderson 1981).Besides allowing the beetles to remain motionless for periods of time, this climbingbehavior could aid in heat conservation, reducing predator risk, and maintainingposition during floods (Folkerts and Donavan 1973).

The genus Gyretes comprises 79 species worldwide, all of which occur in theWestern Hemisphere (Oygur and Wolfe 1991). The taxonomy of the world Gyretesrequires revision. In spite of a limited number of species, North America is noexception as the limits and validity of the existing species are still debated. Four speciesnames have been proposed thus far for Gyretes of America north of Mexico. Gyretessinuatus LeConte (1852) first was described from the Colorado River in California.Gyretes compressus LeConte (1863) subsequently was described from Illinois anddistinguished from G. sinuatus by its narrower shape. There has been, however, muchdebate over the status of the latter two species (Regimbart 1883; Ochs 1949; Walls1974; Poole and Gentili 1996). Regimbart (1883) postulated that G. compressus wasa junior synonym of G. sinuatus. More recently, in his key to the Gyretes of NorthAmerica, Walls (1974) recognized Gyretes compressus as a valid species. This key,however, was not sufficient to identify a number of specimens, according to Walls(1974) himself. This was due to the variation in the height of the pubescent border andin the shape of the midcaudal tooth on the penultimate abdominal tergite in members ofthis genus in North America.

In 1907, Regimbart described a new species, G. californicus, based on a singlefemale. Gyretes californicus was synonymized as a junior subjective synonym ofG. sinuatus by Leech and Chandler (1963) and Walls (1974).

1 Corresponding author (e-mail: [email protected])

538

The Coleopterists Bulletin, 58(4):538–567. 2004.

Previous to G. torosus, described as new here, the most recently described species ofGyretes from America north of Mexico was G. iricolor Young (1947), described fromFlorida. This species represents a valid species as it can be readily distinguished fromother North American congeners by its small size and southeastern distribution.

The purpose of this study is to establish the identity of the North American species ofGyretes, North of Mexico. More specifically, it aims at describing components ofmorphological character variation that could facilitate in the definition of speciesboundaries within this genus. Therefore we intend to evaluate the ability of charactersto discriminate between species, both quantitatively and qualitatively.

Material and Methods

Specimens. A total of 619 specimens from 24 institutional collections listed belowwere examined for this revision including the holotypes of G. iricolor and the syntypesof Gyretes sinuatus and G. compressus. In spite of thorough efforts, the holotype ofG. californicus could not be located. Following is the list of museums with theiracronyms and the names of the curators:

AMNH American Museum of Natural History, L.H. HermanANSP Academy of Natural Sciences, Philadelphia, D. OtteCASC California Academy of Sciences, D.H. KavanaughCISC University of California-Berkeley, C.B. BarrCNIC Biosystematics Research Centre, Agriculture Canada, Y. BousquetCUIC Cornell University, J.K. LiebherrEMUS Utah State University, W.J. HansonFEMP Frost Entomological Museum, J. GrehanFMNH Field Museum of Natural History, P.P. ParrilloFSCA Florida State Collection of Arthropods, division of Plant Industry, M.C.

ThomasICCM Carnegie Museum of Natural History, J.E. RawlinsINHS Illinois Natural History Survey, K. ZeidersJBWM J.B. Wallis Museum, University of Manitoba, R.E. RoughleyLACM Los Angeles County Museum of Natural History, B.V. BrownLSAM Louisiana State Arthropod Museum, V. BaylessMCZC Museum of Comparative Zoology, Harvard University, P.D. PerkinsMSUC Michigan State University, F. StehrROMC Royal Ontario Museum, B. HubleyTAMU College of Agriculture, Texas A and M University, E.G. RileyUAIC University of Arizona, C. OlsonUCMC University of Colorado Museum, M.D. BowersUKAN Snow Entomological Museum, University of Kansas, R.W. BrooksUMMZ Museum of Zoology, University of Michigan, M. O’BrienUSNM National Museum of Natural History Smithsonian Institution, P.J. Spangler

Dissection of Male Genitalia. Determination of the sex of individuals was madesimply by reference to the form of the protarsi. Adult males have broad protarsalsegments that are laterally flattened and padded with adhesive, cup-shaped setae. Toextract the aedeagus, beetles were first relaxed in warm soapy water. A hooked needlewas then inserted into the abdominal opening to extract the genitalia. The aedeagus andlateral lobes were then disarticulated and glued to a point, which was pinned beneaththe specimen. If the abdomen was removed, it was also glued on the same point as thegenitalia. Male genitalia reveal to be fairly similar morphologically and not diagnosticfor the species studied. Accordingly, a description was provided for the genus only.

539THE COLEOPTERISTS BULLETIN 58(4), 2004

Criteria for Ranking Taxa. Defining boundaries between species is oftena controversial subject, especially for closely related and similar species. Ordinationtechniques have proven to be effective for studies dealing with taxonomically difficultcomplexes such as the one found in this study. These methods can identify whichcombination of morphological variables is optimal in distinguishing different species.Principal Components Analysis (PCA) is one of the most commonly used ordinationtechnique for the examination of relationships among taxa in systematic studies (Foottitand Sorensen 1992). Instead of having many characters each explaining its own amount ofvariation between specimens, this analysis combines variables and extracts artificial axes,or components that will each explain more variation than possible for any single variable.A two-dimensional plot of the resulting component scores of the individual specimens canbe used to show clusters of related specimens (Pimentel 1992). Depending on the type ofstudy, these clumps of specimens may coincide with species groups. Once the specieshave been identified, Discriminant Analyses (DA) can be used to examine the ability ofthe variables to discriminate between taxa. This analysis also reduces dimensionality bycreating artificial axes. However, these axes maximize separation among groups ofobjects. Species boundaries can, therefore, be further identified. Furthermore, DA uses themost discriminating variables to provide a function that can predict group membership. Inthis study, statistical analyses were used for an objective evaluation of the groupings usingquantitative morphological measurements. Distributions and qualitative morphologicalfeatures were then examined for support of the results.Morphometric Analysis. Measurements were taken using a Wild M3C stereomi-

croscope with a caliper in one ocular. Where possible 10 specimens of each sex fromeach state were chosen for measurements. Care was taken to select only intact, maturespecimens, to ensure accurate values. A total of 219 specimens (103 females and 116males) were selected for the morphometric analyses. A total of 28 variables weremeasured to the nearest 0.05 mm. The characters and terms used in the morphometricanalyses are defined (Table 1) and illustrated (Figs. 1–7). Unless otherwise stated, allmeasurements represent greatest distance. In order to obtain measures of shape, thefollowing ratios were calculated: SBL/BH, SBL/EW, EL/EW, PTL/PTW, PW/PL,HW/HL, EW/PW, PW/HW.Statistical Analyses. Principal Components Analyses (PCA) and Discriminant

Analyses (DA) were performed with SPSS 9.0� (Statistical Package for the SocialSciences) for Windows and Vax. Because of dimorphism in these beetles, the data wereseparated by gender and initial Principal Components Analyses (PCA) were performedwith 103 females and 116 males. Many specimens had broken or missing parts, leavingworking samples of 69 females and 63 males with complete data. These specimenswere used in the PCA without being classified a priori. The components that accountedfor the majority of the total variance were examined and the most highly loadedvariables (with the highest eigenvector coefficients) were considered for any furtheranalyses. A scatterplot of the component scores of the specimens was created to findclustered individuals. The resulting clusters were given the arbitrary labels of SpeciesGroup 1, 2, and 3. The specimens within the clusters were examined for distinguishingqualitative features. All specimens were then classified using these qualitativecharacters. Using 50% of the population, a total of 36 female and 47 male specimenswere suitable for the DA. Discriminant Analyses were performed to clarify moreconclusively the species boundaries, reduce the variable list, and confirm howaccurately the quantitative variables were able to correctly classify given specimensinto their respective species groups. The holotypes of the known described species thenwere placed into the DA to determine into which species complex they were classified.Illustrations, Maps and SEM Photos. Illustrations were drawn with the aid of

a camera lucida mounted on an Olympus SZH10 stereoscope. To facilitate

540 THE COLEOPTERISTS BULLETIN 58(4), 2004

Table 1. Morphometric characters measured on adults of Gyretes.

Variable Description

1 Width of flagellum (AFW) measured at maximum width whenthe tip of the antenna is at itswidest angle

2 Labral width (LW) measured along midline3 Clypeal length (CL) measured along midline from

anterior margin to posteriormargin

4 Clypeal width (CW) measured along posterior margin5 Distance between dorsal and

ventral eye (DDV)minimum distance from eyes at

lateral view, measured whenventral eye margin isperpendicular to rule

6 Dorsal eye length (DEL) measured from anterior margin toposterior margin

7 Distance between dorsal eyes (DD) minimum distance between thedorsal eyes

8 Head length (HL)* measured along midline from themargin of the clypeus to theposterior margin of the dorsaleyes

9 Dorsal head width (DHW) measured near posterior margin10 Ventral head width (VHW) measured between outer margins

of ventral eyes11 Pronotal pubescent border

height (PPH)laterally measured within 0.05 mm

of anterior margin of pronotum12 Pronotal length (PL)* measured along midline from

anterior margin to posteriormargin

13 Pronotal width (PW) measured at posterior margin14 Body height (BH) measured from apex of elytral

arch to mesocoxae15 Elytral length (EL)* measured along midline from the

dorsal posterior margin of thepronotum to the apex ofthe elytron

16 Elytral height (EH) measured from the apex of elytralarch to ventral margin of elytron

17 Elytral width (EW) measured at greatest transversewidth across both elytra

18 Medial elytral pubescent borderheight (EPH)

measured medially, at the samepoint as HB and HEL

19 Length of protibia (PTL) Refer to Figure 2 (PTL)20 Width of protibia (PTW) Refer to Figure 2 (PTW)21 Length of profemur (PFL) Refer to Figure 2 (PFL)22 Width of profemur (PFW) Refer to Figure 2 (PFW)23 Length of hind tibia (HTL) Refer to Figure 2 (HTL)24 Width of hind tibia (HTW) Refer to Figure 2 (HTW)25 Length of hind femur (HFL) Refer to Figure 2 (HFL)26 Width of hind femur (HFW) Refer to Figure 2 (HFW)27 Length of male protarsi (MTL) Refer to Figure 5 (MTL)28 Width of male protarsi (MTW) Refer to Figure 5 (MTW)

Standardized body length (SBL) Sum of DHL þ PL þ EL

* all dorsal measurements were taken when the tip of the clypeus and the apex of the elytra are on an equalplane of focus.


comparisons, homologous structures are consistent in scale and aspects. Maps arepresented using RangeMapper 2.0� to illustrate known distributions of the speciesstudied. Localities are from specimens examined in this study. For examination of thepronotal microreticulation, selected specimens were gold-coated and photographedthrough a Cambridge Stereoscan 120 scanning-electron microscope at LaurentianUniversity, Sudbury, Ontario.

Fig. 1. Dorsal habitus (semi-diagrammatic) of Gyretes specimen, illustrating measurementpoints (acronyms are given in Table 1).


Results

Results of the Multivariate Analyses. The Principal Components Analysesrevealed three components for both males and females, explaining 82.6% and 82.9%of the total variance respectively (Table 2). The first component explained 37.4% of thetotal variance for males (eigenvalue ¼ 10.5), 43.4% of the total variance for females(eigenvalue ¼ 11.3) and was highly loaded with general body measurements for bothmales (eigenvector coefficients: DEL¼ 0.83, PW¼ 0.78, BH¼ 0.78, EL¼ 0.91, EW¼0.81) and females (eigenvector coefficients: DEL¼ 0.82, PW¼ 0.82, BH¼ 0.81, EL¼0.93, EW¼ 0.80, HFL¼ 0.79) (Tables 2, 3). The second component explained 31.1%

Fig. 2. Ventral habitus (semi-diagrammatic) of Gyretes specimen, illustrating measurementpoints (acronyms are given in Table 1).


of the total variance for males (eigenvalue¼ 8.7) and 25.6% for females (eigenvalue¼6.6). This component was highly loaded by pubescence for females (eigenvectorcoefficients: PPH ¼ 0.79, EPH ¼ 0.96) and pubescence and forelegs for males(eigenvector coefficients: PPH¼ 0.80, EPH¼ 0.92, PTW¼ 0.81, MTW¼ 0.82). Thethird component was highly loaded by clypeal length for both males (eigenvectorcoefficient: CL¼ 0.79) and females (eigenvector coefficient: CL¼ 0.87) and explained14.1% of the total variance for males (eigenvalue¼3.9) and 13.9% of the total variancefor females (eigenvalue ¼ 3.6) (Tables 2, 3). An ordination plot of the componentscores of the first two components demonstrated that there is a slight horseshoe or archpattern for both female (Fig. 8) and male specimens (Fig. 9). Clusters of specimenswere arbitrarily named Species Group 1, 2 and 3. These groups were examined forqualitative distinguishing features (e.g., lateral body shape and presence or absence ofa tooth on the penultimate tergite). The remaining specimens were then placed into theirrespective groups by these qualitative characteristics.

From the PCA, ten variables were found to be highly loaded (eigenvector coefficient. 0.78) on the first three components for males and nine variables for females (Table3). These variables were then selected for Discriminant Analysis using half thepopulation and the classification groups of the PCA in order to attempt to more clearlyobjectively classify individuals. Discriminant Analysis successfully differentiated threegroups, correctly classifying 93.6% of the female specimens and 98.1% of malespecimens (Table 4).

A scatterplot of functions 1 and 2 was created to aid in determining the boundariesof the species groups around their respective centroids (Figs. 10, 11). Using theseboundaries, the functions were tested on the second half of the specimens with Chi-squared test and were found to correctly classify 90.9% of the males (chi-square ¼67.4, phi ¼ 1.2, P , 0.05) and 80.4% of the females (chi-square ¼ 59.8, phi ¼ 1.1,P , 0.05).

Discriminant Analysis classified the male holotype of G. iricolor as Centroid 1 with98.3% probability. Some measurements could not be measured for the syntypes ofG. sinuatus and G. compressus and accordingly were unavailable for the DA. A modifiedDA using eight of the nine female variables classified the syntype of G. compressus asCentroid 2 with 99.7% accuracy. The syntype of G. sinuatus was missing data for one

Fig. 3. Lateral habitus (semi-diagrammatic) of Gyretes specimen, illustrating measurementpoints (acronyms are given in Table 1).


further female variable but was classified as Centroid 2 with 96.6% accuracy using sevenof the nine DA variables.Species Recognition. Those specimens of Centroid 1 (Figs. 10, 11) had an angular

body outline, no tooth on the penultimate tergite and number of other similarities thatwill be mentioned below. These specimens resembled descriptions of Gyretes iricolor.The holotype of G. iricolor was classified in this species group by both qualitative andquantitative methods.

The specimens called Centroid 2 (Figs. 10, 11) corresponded to many specimenspreviously identified as G. compressus and some specimens classified as G. sinuatus.These specimens often had very distinct pronotal microreticulation at a magnificationof 403 and a distinct tooth on the penultimate tergite while their shape was variable.The statistical results of a modified DA placed the syntypes of G. sinuatus and

Figs. 4–7. Habitus (semi-diagrammatic) of selected structures of Gyretes specimen, illus-trating measurement points. 4) Dorsal eye; 5) male protarsi; 6) head, frontal aspect; 7) antenna,dorsal, aspect; acronyms (Table 1).


G. compressus with Centroid 2. The shared qualitative features of this group supportedthese results.

The specimens grouped as Centroid 3 were often previously identified as G. sinuatususing Walls’key (1974) in that they had no tooth to a very slight projection on thepenultimate abdominal tergite. However, these specimens did not have distinct pro-notal microreticulation, which was found on both syntypes of G. sinuatus andG. compressus. This species is here described as G. torosus new species.

Description of Adults of the Genus Gyretes Brulle of America North of Mexico(Figs. 12–23)

Color. Dorsal surface black and shiny. Ventral surface dark red-brown to black.

Body. Ovate, attenuate at both ends, strongly convex; SBL 4.5–6.0 mm. Head. Deeply retractedinto pronotum; 2.0–2.5 times wider than long, with micropunctures and microreticulation present.Dorsal and ventral eyes separated by large interorbital area; ventral eyes somewhat larger than andslightly posterior to dorsal eyes. Second antennal segment (pedicel) is spade-shaped, relativelysymmetrical. Clypeus transverse and narrow, with micropunctures and microreticulation. Labrumrelatively transverse. Mouthparts. Maxillary palps with terminal segment that widens distally,squared at apex. Galea absent. Labial palps with terminal segment lobate and curved. Thorax.Pronotum 2.2 to 3.0 times wider than long, overlapping both head and elytra. Scutellum concealed.Elytrawidest at apical 1/3; 1.2 to 1.7 times longer than wide; width of margined pubescence variable;punctures present under pubescence; truncate apically, slightly produced or sinuous; without distinctstriae but may have micropunctures and a small area of microreticulation at apex of females. Maleprotarsi strongly widened into a broad crescent shape with modified adhesive setae that are short anddistinctly cup-shaped. Abdomen. Last abdominal segment elongate and conical; dorsal setaeabsent at posterior 1/3. Gonocoxosternite with medial ridge of macrosetae. Male Genitalia.Aedeagus simple, elongate, tapered distally, slightly upturned, shorter than parameres. Parameresdorsally flattened, slightly expanded distally (Fig. 13).

Key to Adults of North American Species of Gyretes Brull�

Protarsi flattened laterally into broad crescent, with cup-shaped modified (Figs.15, 16); lateral pubescence extending to elytral apex; elytral microreticulationlacking - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - A (male)

Protarsi narrow and relatively unmodified (Fig. 14); lateral pubescence generallyabsent at elytral apex; microreticulation generally distinct at apex ofelytra - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - B (female)

Table 2. Eigenvalues, percent variance explained, and cumulative percent variance explainedfor each component from Principal Components Analysis performed for morphometric data ofspecies of Gyretes.

Component Eigenvalue% of variance

explained Cumulative %

Male

1 10.47 37.39 37.392 8.71 31.12 68.513 3.94 14.07 82.57

Female

1 11.29 43.42 43.422 6.65 25.60 69.023 3.62 13.90 82.92


A (Male)

1. Pronotum with rhomboid microreticulation that is distinct at magnification 403(may be faint or sparse in Oklahoma specimens) (Figs. 17, 19); penultimate tergitewith distinct midcaudal tooth dorsally (less distinct in Texas specimens) (Fig. 12MT); California to Alabama, north to Indiana, Virginia (Fig. 24) - - - - - - - G. sinuatus

Microreticulation on pronotal surface transversely elongated and not distinct atmagnification 403 (Fig. 18); penultimate tergite, at most, slightly convex mesallybut lacking distinct midcaudal tooth - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2.

2. Outline of body angular in lateral view; PW, 2.20 mm; EPH, 0.20 mm; EW, 2.40mm; SBL 4.49–5.06 mm (Table 5); Alabama and Florida (Fig. 25) - - - - - - - G. iricolor

Outline of body more evenly rounded in lateral view; PW . 2.20 mm; EPH . 0.20mm; EW . 2.40 mm; SBL 4.99–5.76 mm (Table 5); Arizona to Texas (Fig. 26)- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - G. torosus

B (Female)

1. Apex of elytra extended distinctly along midline (Fig. 22), decurved in lateral view(Fig. 20); EW , 2.35 mm; HFL , 0.71 mm (Table 5); penultimate tergite, at most,

Table 3. Variable loadings (Eigenvector Coefficients) for each component from PrincipalComponents Analysis for morphometric data of species of Gyretes. Shaded numbers indicate thehighest loadings for each component (the most highly loaded variables were subsequentlyincluded in Analyses; see material and methods).

Male Female

Component 1 2 3 Component 1 2 3

AFW 0.50 0.08 0.59 AFW 0.55 �0.04 0.64LW 0.58 0.72 0.23 LW 0.58 0.70 0.30CL �0.06 0.11 0:79 CL �0.06 0.15 0:87CW 0.60 0.56 0.33 CW 0.61 0.60 0.28DDV 0.62 0.59 0.13 DDV 0.54 0.65 0.23DEL 0:83 0.18 0.20 DEL 0:82 0.24 0.20DD 0.55 0.72 0.33 DD 0.62 0.66 0.29HL 0.56 0.17 0.63 HL 0.56 0.13 0.54DHW 0.74 0.53 0.35 DHW 0.76 0.51 0.34VHW 0.74 0.53 0.35 VHW 0.77 0.48 0.35PPH 0.48 0:80 �0.11 PPH 0.49 0:79 �0.05PL 0.43 0.40 0.63 PL 0.54 0.38 0.59PW 0:78 0.54 0.22 PW 0:82 0.45 0.20BH 0:78 0.46 0.19 BH 0:81 0.36 0.13EL 0:91 0.11 0.16 EL 0:93 0.10 0.21EH 0.71 0.31 0.05 EH 0.76 0.29 0.12EW 0:81 0.52 0.08 EW 0:80 0.49 0.10EPH 0.22 0:92 0.01 EPH �0.07 0:96 0.06PTL 0.59 0.48 0.44 PTL 0.62 0.48 0.44PTW 0.34 0:81 0.36 PTW 0.53 0.66 0.29PFL 0.63 0.60 0.36 PFL 0.72 0.54 0.32PFW 0.38 0.64 0.48 PFW 0.55 0.52 0.38HTL 0.70 0.49 0.29 HTL 0.64 0.43 0.40HTW 0.65 0.62 0.29 HTW 0.67 0.56 0.35HFL 0.75 0.51 0.22 HFL 0:79 0.49 0.20HFW 0.65 0.35 0.52 HFW 0.71 0.23 0.50MTL 0.39 0.74 0.32MTW 0.06 0:82 0.44


slightly convex mesally but lacking distinct midcaudal tooth; Alabama and Florida(Fig. 25) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - G. iricolor

Apex of elytra at most slightly produced less extended along midline (Fig. 23), notdecurved in lateral view (Fig. 21); EW . 2.35 mm; HFL . 0.71 mm (Table 5);penultimate tergite may or may not have a strongly developed tooth dorsally; westof Florida, and Virginia - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2.

2. Pronotum with rhomboid microreticulation distinct at magnification 403 (Figs. 17,19) (may be faint or sparse in Oklahoma specimens); WEL 2.38–2.97 mm (mean¼2.59 mm) (Table 5); penultimate tergite with distinct midcaudal tooth dorsally

Table 4. Unstandardized coefficients, group centroids, eigenvalues, percent varianceexplained, cumulative percent variance explained, and canonical correlation coefficient of thetwo functions created from Discriminant Analysis performed for males and females separately(percentage of the specimens correctly classified is included for each gender).

Function 1 Function 2

Male

Unstandardized coefficients

LDE 23.16 �2.33PUP 17.91 0.82WMT �49.62 43.36(Constant) �6.56 �11.85

Functions at Group Centroids

Group 1 �2.54 �2.10Group 2 �0.53 0.84Group 3 3.20 �0.79

Eigenvalues 3.79 1.37% of Variance 73.49 26.51Cumulative % 73.49 100.00Canonical Correlation 0.89 0.76Original grouped cases correctly classified 98.1%

Female

Unstandardized coefficients

LC �26.20 122.09HB 8.81 �8.22PUP 15.02 7.83(Constant) �23.27 �6.72

Functions at Group Centroids

Group 1 �5.37 �1.36Group 2 �0.61 0.86Group 3 2.74 �0.69

Eigenvalues 7.33 0.86% of Variance 89.53 10.47Cumulative % 89.53 100.00Canonical Correlation 0.94 0.68Original grouped cases correctly classified 93.6%

Figs. 8–9. Component scores of the first two components from the Principal ComponentsAnalysis. 8) Males (n¼ 63); 9) females (n¼ 69). Numbers refer to arbitrary group labels (refer tomethodology).


(less distinct in Texas specimens); California to Alabama, north to Indiana, Virginia(Fig. 24) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - G. sinuatus

Pronotum with transversely elongated microreticulation not distinct at magnification403 (Fig. 9); WEL 2.43–3.03 mm (mean¼2.80 mm) (Table 5); penultimate tergite,at most, slightly convex mesally but lacking distinct midcaudal tooth; Arizona toTexas (Fig. 26) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - G. torosus

1. Gyretes iricolor Young 1947(Figs. 16, 18, 20, 22, 25)

G. iricolor Young 1947:31 (orig. descr.)G. iricolor Young 1954: 158 (descr.)G. iricolor Walls 1974: 7 (taxon. rev.)G. iricolor Poole and Gentili 1996: 271 (cat.)

Fig. 10. Discriminant scores of the two functions created from the Discriminant Analysisperformed on males; diamonds¼ species-group 1; squares¼ species-group 2, triangles¼ species-group 3.


Notes About Type Material of G. iricolor. The holotype is a male specimen (UMMZ)glued to a point with the following labels: Holmes Co., Fla. X.18.41 #392, Sandy Creek - FNY[handwritten]/Holotype male, Gyretes iricolor 1947 F.N. Young Fla. Ent.33:31/Vidit J.J. Babin2002 [white rectangular label]. The dorsal surface has an oily film, the ventral surface is coveredwith fine dirt particles, the last abdominal tergite is hidden, the last abdominal segment is partiallyhidden, and the body is black. Aedeagus and parameres are attached to the body.

Diagnosis. This species has a smaller body size and is more attenuated at both ends than theother North American species. Pronotum with microreticulation not distinct at a magnification of403, and with scattered faint punctures. Midcaudal tooth on the penultimate tergite absent. Bodyoutline angular in lateral view, with more sharply tapering posterior end. Female elytral apexextending strongly along midline, decurved in lateral view (Figs. 20, 22). Epipleuron yellow todark-orange.

Redescription. Microsculpture and punctation. Pronotal microreticulation transverselyelongated, not distinct at a magnification of 403. A small field of distinct rhomboidmicroreticulation present on the female elytral apex. Micropunctation may occur faintly andsparsely on pronotum and elytra. Measurements (Table 5). Pronotum 1.2–1.5 times broader thanhead. Elytra 1.1–1.2 times broader than pronotum. Standardized body length 2.0–2.2 times greater

Fig. 11. Discriminant scores of the two functions created from the Discriminant Analysisperformed on females; diamonds ¼ species-group 1; squares ¼ species-group 2, triangles ¼species-group 3.


than elytral width. Elytral pubescence generally narrower (0.1–0.2 mm), broadening posteriorlygradually. Female pubescent band reduced to 1–2 hairs at elytral apex. Male protibia not stronglywidened distally, 2.4–2.9 times longer than wide.

Remarks. The angular body shape is more pronounced in females and in males andfemales from Florida. The penultimate tergite can be slightly sinuous, and may bemistaken for a midcaudal tooth laterally.Distribution. Alabama and Florida.Material Examined. Holotype, and 107 specimens with the following label data:

ALABAMA: Styx R., Baldwin Co., at 64, 26.V.1976, coll. G.W. Wolfe (1, FSCA);Conecuh Co., 13 km E. Evergreen, 19.IV.1980, coll. W.E. Steiner (1, USNM); BushyCr., Conecuh Co., 1 mi. SW Lenox, at Co.Rd. 6, 22.V.1988, coll. C.B. Barr (2, CISC20; 5, LSAM); Old Town Cr., Conecuh Co., 10 km E. Evergreen, at Hwy 31, 27–29.IV.1987, coll. R.G. Beutel, R.E. Roughley (1, JBWM); Old Town Cr., ConecuhCo., 10 mi. E. Evergreen, at Hwy 31, 5.V.1991, coll. I.S. Askevold (10, JBWM); SandyCr., Conecuh Co., at Co.Rd. 42, 1 km E. Evergreen, undercut stream bank, 26.IV.1987,coll. R.G. Beutel, R.E. Roughley (18, JBWM); Silas Cr., Escambia Co., at Co.Rd. 4,SE Brewton, 14.IX.1971, coll. G.W. Folkerts (3, USNM); Sandy Cr., Geneva Co., 4.5mi. SW Geneva, 15.IX.1971, coll. G.W. Folkerts (1, TAMU; 10, USNM). FLORIDA:Topotype, 1958, coll. PJ Spangler (1, USNM); Escambia R., Escambia Co.,30.III.1953, coll. S.S.R. (1, ANSP); Sandy Cr., Holmes Co., near Ponce de Leon,21.VIII.1951, coll. F.N. Young (2, AMNH; 28, CASC; 1 CNIC; 2, CUIC; 8, FSCA; 2ICCM; 4, UKAN; 5, UMMZ); Sandy Cr., Holmes Co., near Ponce de Leon, topotype,21.VIII.1951, coll. F.N. Young (1, USNM).

2. Gyretes sinuatus LeConte 1852(Figs. 12, 13, 17, 19, 21, 23, 24)

G. sinuatus LeConte 1852: 210 (orig. descr.)G. compressus LeConte 1863: 23 (orig. descr.)G. sinuatus LeConte 1868: 373 (descr.)G. compressus LeConte 1868: 373 (descr.)G. sinuatusG. compressus syn. Regimbart 1883: 399 (descr.)

G. californicus Regimbart 1907: 188 (orig. descr.)G. sinuatus Blatchley 1910: 242 (descr.)

Fig. 12. Habitus of G. sinuatus. MT ¼midcaudal tooth on penultimate tergite.


G. sinuatus Ochs 1929: 74 (taxon. rev.)G. sinuatusG. compressus syn. Ochs 1949: 294 (descr.)

G. sinuatusG. californicus syn. Leech and Chandler 1963: 330 (descr.)

G. sinuatus McCleve 1978: 257 (note)

Figs. 13–15. Selected structures of Gyretes. 13) Male genitalia of G. sinuatus at 703; 14–15)protarsus of G. torosus new species. 14) Female; 15) male.


G. sinuatusG. californicus syn. Walls 1974:7 (descr.)

G. compressus Walls 1974: 7 (descr.)G. sinuatusG. compressus syn. Poole and Gentili 1996: 271 (cat.)

G. californicus Poole and Gentili 1996: 271. New Junior Synonym (cat.)

Synonyms.

G. compressus LeConte 1863G. californicus Regimbart 1907

Notes About Type Material of G. sinuatus. LeConte did not explicitly designateholotypes in his descriptions. The syntype studied is a female specimen (MCZC) gluedto a point with the following labels: gold circular tag/ Type 6109 [red label]/ Gyretessinuatus Lec. [handwritten]/ Vidit J.J. Babin 2002 [white rectangular label]. LeConteindicated that the type locality was Colorado River. The ventral surface is covered inglue and dirt, penultimate tergite is hidden, last abdominal segment is partially exposed,body is more reddish than black.Notes AboutTypeMaterial ofG. compressus. LeConte did not explicitly designate

holotypes in his descriptions. The syntype studied is a female specimen (MCZC)pinned through the body with the following labels: gold circular tag/Type 6110 [redlabel]/ G. compressus Lec. [handwritten]/ Vidit J.J. Babin 2002 [white rectangularlabel]. LeConte indicated that the type locality was Quincy, Illinois. Dorsal surface withdirt and patches of glue and film. Ventral surface with some dirt particles. Penultimatetergite is hidden, last abdominal segment is partially exposed, body is red-black.

Figs. 16–19. Selected structures of Gyretes. 16) Male protarsus of G. iricolor at 1743 17–19)pronotal microsculpture. 17) G. sinuatus at 7323 18) G. iricolor at 3663 19) G. sinuatus at 3663.


Diagnosis. This species is variable in size but is generally larger than G. iricolor andsmaller than G. torosus new species. Body is not as attenuated as G. iricolor in dorsalview but it is not as rounded as G. torosus new species. Pronotum with rounded meshmicroreticulation seen at a magnification of 403with faint micropunctures. Midcaudaltooth on the penultimate tergite present. Body outline is variable but is generally ovate.Female elytral apex at most slightly produced (Figs. 21, 23). Epipleuron orange to darkbrown, generally darker than G. iricolor.

Redescription. Microsculpture and punctation. Pronotal microreticulation rhomboid anddistinct at a magnification of 403. A small field of distinct rhomboid microreticulation present onthe female elytral apex. Micropunctation may occur on pronotum and elytra. Measurements(Table 5). Pronotum 1.3–1.8 times broader than head. Elytra 1.0–1.2 times broader than pronotum.Standardized body length 1.9–2.3 times greater than elytral width. Elytral pubescence variable(0.1–0.6 mm), generally thicker than G. iricolor. Female pubescent band is reduced to 1–2 hairs atelytral apex. Male protibia more strongly widened distally than G. iricolor, being 2.2–2.8 timeslonger than wide.

Remarks. Body outline rounded to slightly angular in southeastern beetles.Midcaudal tooth of penultimate tergite often more pronounced in females than males.This tooth is generally very distinct but may be reduced to a small projection in Texasand California specimens. A general increase in body size and width of elytral

Figs. 20–23. Selected structures of female Gyretes. 20–21) Lateral habitus. 20) Gyretesiricolor; 21) G. sinuatus. 22–23) Apex of elytra, dorsal aspect. 22) Gyretes iricolor; 23) G.sinuatus.


pubescence occurs in an east-to-west pattern. Pronotal microreticulation is faint andsparse (occurring more laterally) in Oklahoma specimens. Female elytral apex does notextend strongly along midline but may be slightly produced, giving a slight projectingin lateral perspective.Distribution. California to Alabama, north to Indiana and Illinois, Virginia.Material Examined. Two syntypes and 393 specimens with the following label data:

ALABAMA: Borden Cr., Lawrence Co., Bankhead Natl. For., at F.S. Rd. 224,16.V.1988, coll. C.B. Barr (2, CISC; 4, LSAM); Lawrence Co., 8 mi. S. Mount Hope,22.V.1988, coll. Paul and Phyllis Spangler (1, USNM); Lawrence Co., 5.5 mi. S.Youngtown, 23.V.1988, coll. Paul and Phyllis Spangler (2, USNM); Lawrence Co., 5 mi.S. Youngtown, 26.V.1988, coll. Paul and Phyllis Spangler (3, USNM); Brushy Cr.,Peterman, Monroe Co., 15.VI.1991, coll. I.S. Askevold (5, JBWM); Peterman, MonroeCo., 11.IV.1980, coll. W.E. Steiner (1, USNM); Brushy Cr., Monroe Co., 0.2 km E.Peterman, at Rd. 30, undercut stream bank, 29.IV.1987, coll. R.G. Beutel, R.E. Roughley(8, JBWM); Line Cr., Montgomery-Mason Co. line, at I-85, 9.VI.1972, coll. G.W.Folkerts (1, TAMU); Watermelon Cr., Russel Co., 5 km S. Seale, 8.IV.1980, coll. W.E.Steiner (1, USNM); Indian Cr., Walker Co., 7.5 mi. S. Oakman, at Ala 69, 7.IX.1973, coll.G.W. Folkerts (2, TAMU). ARIZONA: (1, ICCM; 1, INHS); Yuma (1, ANSP); GilaValley, 3 mi. SE Bylas, 2,000 ft, at light, 18.VII.1952, coll. R.B. and R.K Selander (1,USNM). ARKANSAS: Saline R., Howard Co., at Hwy. 4, N. Dierks, 12.IV.1987, coll.C.B. Barr (2, CISC; 3, LSAM). CALIFORNIA: (2, ICCM; 1, MCZC). INDIANA:Green Co. Stream, Greene Co., 2 mi. S. Bloomfield, 7.IX.1963, coll. F.N. Young (1,FSCA); Fish Cr., Owen Co., Nr. Freedom, 9.VIII.1971, coll. F.N. Young (6, FSCA).KANSAS: Douglas Co., 17.VI.1922, coll. J. Marion Bruer (1, MCZC). LOUISIANA:(3, CASC); Vowell’s Mill (4, AMNH; 11, CASC; 1, FSCA; 1, UCMC); Vowell’s Mill,

Fig. 24. Known distribution of Gyretes sinuatus in America north of Mexico.


coll. A. Lustgurs (1, AMNH); Beaugard Co. (Presumed to be Beauregard), 13.VIII.28,coll. R.H. Beamer Jr. (10, UKAN); Little Comite Cr., East Feliciana Par., Hwy 19,16.IV.1983, coll. T.W. Walker (1, LSAM); Hog Branch Cr., Livingston Par., 1980 (1,LSAM); Kisatchie Bayou, Natchitoches Par., Kisatchie Natl. For., S. Kisatchie BayouCgd., 18.VI.1988, coll. C.B. Barr (1, CISC; 1, LSAM); Abita Cr., St. Tammany Par., atAbita Springs, LA 435, 29.IV.1981, coll. C.B. Barr (2, CISC; 1, LSAM); Abita Cr., St.Tammany Par., at Abita Springs, LA 435, collected in roots, 29.IV.1981, coll. C.B. Barr(5, LSAM); Natalbany R., Tangipahoa Par., W. Independence, LA 40, 13.VIII.1980, coll.C.B. Barr (2, CISC); Natalbany R., Tangipahoa Par., W. Independence; LA 40, collectedon wood, 13.VIII.1980, coll. C.B. Barr (2, LSAM); Comrade Cr., Vernon Par., 0.5 mi. W.Kerthwood, 7.X.1967, coll. J.G. Wells (2, FSCA). MISSISSIPPI: Richton, 3.III.1932,coll. H. Dietrich (1, CUIC); Homochita R., Lincoln Co., at 550, 25.IV.1976, coll. G.W.Wolfe (2, FSCA); Marion Co., 6 mi. E. Columbia, 21.IV.1979, coll. Paul K. Lago (1,FSCA); Pearl River Co., 1 mi. SW Silver Run, 26.V.1980, coll. Paul K. Lago (1, FSCA);Wilkinson Co., 4 mi. W. Wilkinson, 27.V.1980, coll. Paul K. Lago (1, FSCA).MISSOURI: Little Black R., Poplar Bluff, 12 mi. S. Rt. 160, 23.IV.1956, coll. P.J.Spangler (1, USNM). NEW MEXICO: (2, CASC); Carlsbad (1, USNM); Carlsbad,27.VIII.1934, coll. Carl J. Drake (1, FSCA); Las Cruces, Dona Ana Co., 1.IX.1953, coll.R.X. Schick (2, LACM). OKLAHOMA: Latimer Co., VIII.1982, coll. K. Stephan (32,FSCA); Latimer Co., VIII.1986, coll. K. Stephen (5, FSCA). TENNESSEE: Elmwood,coll. J.Corse (1, CASC). TEXAS: (2, AMNH; 3, ANSP; 6, ICCM; 7, INHS; 1, MCZC;20, USNM); coll. W.E. Dietz (2, MCZC); coll. Fuchs and Leach (1, CASC); Green RiverSurvey, 12.5.1981 (1, ANSP); Columbus (3, MCZC; 19 USNM); Columbus, coll. E.A.Schwarz (1, CASC; 9 USNM); Dallas (2, ANSP; 2, MCZC; 3, MSUC; 4, UKAN; 2,USNM); Dallas, coll. F.C. Bowditch (2, FSCA); Dallas, coll. Liebeck (1, FSCA); Ft.Ringgold, 20.V.1995 (1, CASC; 6 USNM); Guadalupe R. nr. Victoria, 23.VIII.62, coll.S.S. Roback (1, ANSP); Guadalupe R., Sequin, 9.4.1950, coll. T.D. IV (6, ANSP);Guadalupe R., nr Bloomington, 3 mi. below DuPont Plant, 20.VIII.1952, coll. T.D. IV (1,ANSP); Guadalupe R., S. Victoria, below DuPont Plant, 21.VIII.1952, coll. T.D. IV (4,ANSP); Laredo, 12.XII.1930, coll. Eugene Ray (28, FMNH); Presidio, 17.VI.1968, coll.J.E. Hafernik (2, TAMU); Presidio, 18.VI.1968, coll. J.E. Hafernik (3, TAMU); Presidio,at black light, 18.VI.1968, coll. J.E. Hafernik (2, TAMU); Santa Elena Canyon, Big BendNat. Park, 24.IV.1953, coll. B.J. Adelson (43, CASC); Rio Grande Camp, Big Bend Nat.Park, at UV light trap, 25.VIII.1971, coll. D.P. Levin (2, LACM); Little Brazos R., BrazosCo., at TX 21, 20.X.1995, coll. S.K. Jasper (1, TAMU); Brewster Co., Boquillas Camp,Big Bend N.M., 6.VIII.1963, coll. J. Doyen (1, CISC); Cameron Co., 8.3.28, coll. J.G.Shaw (1, UKAN); Dimmit Co., coll. A.W. (1, CASC); Hidalgo Co., 30.VII.1928, coll.R.H. Beamer (3, UKAN); Cascade Caverns, Boerne, Kendall Co., 21.VIII.1981, coll.W.E. Steiner (1, USNM); Kerrville, Kerr Co., 17.IX.1977, coll. Hanson and Hsiao (1,EMUS); Lee Co., 4.IV.1907 (1, MSUC); Long King Cr., Polk Co., 0.5 mi. W. Livingston,14.VII.1962, coll. H.R. Burke (4, TAMU); Shafter, Presidio Co., 22.VI.1968, coll. J.E.Hafernik (1, TAMU); Starr Co., 30.VII.28, coll. R.H. Beamer (6, UKAN); Guadalupe R.,Victoria, Victoria Co., 0.5 mi. below DuPont pump house, 12.VIII.73, coll. J. Richardson(2, ANSP); San Gabriel R., Williamson Co., at Hwy 95, 16.VII.1972, coll. Phelps andSweet (27, TAMU). VIRGINIA: (1, MCZC). NO LOCALITY: (2, CUIC; 1, MCZC).

3. Gyretes torosus Babin, new species(Figs. 14, 15, 26)

Notes About Type Material of Gyretes torosus New Species. The holotype isa male specimen (USNM) glued to a point with the following labels: ARIZ. YavapaiCo., Convergence Oak Cr. and Verde R. 10 July, 1979. M.W. Sanderson UV light trap.


Table 5. Descriptive statistics (mm) for North American species of Gyretes. Explanations ofvariable abbreviations and their measurements given in Table 1.

Gyretes iricolor Gyretes sinuatus Gyretes a n. sp.

Malen ¼ 15

Femalen ¼ 14

Male(n ¼ 78)

Female(n ¼ 62)

Male(n ¼ 22)

Female(n ¼ 26)

AFW

Range 0.14–0.15 0.14–0.16 0.14–0.18 0.14–0.18 0.14–0.17 0.14–0.17Mean 0.14 0.15 0.16 0.16 0.15 0.16SD 0.002 0.005 0.01 0.01 0.01 0.01

LW

Range 0.51–0.59 0.52–0.57 0.55–0.74 0.57–0.73 0.60–0.71 0.61–0.73Mean 0.55 0.55 0.65 0.65 0.67 0.68SD 0.02 0.01 0.04 0.04 0.03 0.03

CL

Range 0.14–0.17 0.14–0.17 0.14–0.19 0.14–0.20 0.14–0.17 0.14–0.17Mean 0.16 0.15 0.17 0.17 0.15 0.16SD 0.01 0.01 0.01 0.01 0.01 0.01

CW

Range 0.62–0.71 0.63–0.70 0.62–0.86 0.68–0.83 0.69–0.79 0.71–0.82Mean 0.66 0.67 0.73 0.74 0.74 0.77SD 0.03 0.02 0.04 0.04 0.03 0.03

DD

Range 0.64–0.73 0.67–0.73 0.69–0.95 0.74–0.93 0.74–0.86 0.76–0.90Mean 0.68 0.70 0.80 0.81 0.80 0.84SD 0.02 0.02 0.04 0.04 0.03 0.04

DDV

Range 0.25–0.30 0.26–0.30 0.27–0.38 0.28–0.38 0.29–0.36 0.29–0.36Mean 0.28 0.28 0.32 0.32 0.33 0.34SD 0.01 0.01 0.02 0.02 0.02 0.02

DEL

Range 0.42–0.48 0.43–0.48 0.44–0.54 0.43–0.54 0.47–0.51 0.46–0.55Mean 0.45 0.45 0.48 0.49 0.49 0.50SD 0.02 0.02 0.02 0.02 0.01 0.02

HL

Range 0.64–0.75 0.69–0.76 0.67–0.88 0.67–0.89 0.69–0.80 0.69–0.84Mean 0.70 0.72 0.76 0.76 0.74 0.77SD 0.03 0.03 0.04 0.05 0.03 0.03

DHW

Range 1.40–1.55 1.40–1.53 1.47–1.83 1.55–1.81 1.55–1.75 1.59–1.82Mean 1.46 1.47 1.64 1.66 1.67 1.73SD 0.04 0.05 0.7 0.07 0.05 0.06

VHW

Range 1.37–1.52 1.39–1.53 1.48–1.81 1.52–1.89 1.55–1.73 1.54–1.79Mean 1.44 1.45 1.62 1.65 1.64 1.71SD 0.03 0.05 0.07 0.07 0.05 0.06


Table 5. Continued.


Malen ¼ 15

Femalen ¼ 14

Male(n ¼ 78)

Female(n ¼ 62)

Male(n ¼ 22)

Female(n ¼ 26)

PPH

Range 0.24–0.38 0.21–0.40 0.36–0.72 0.40–0.69 0.57–0.73 0.57–0.74Mean 0.32 0.33 0.55 0.57 0.66 0.67SD 0.04 0.05 0.08 0.07 0.04 0.05

PL

Range 0.76–0.91 0.76–0.85 0.81–1.07 0.76–1.07 0.86–0.99 0.84–1.00Mean 0.83 0.79 0.94 0.92 0.92 0.92SD 0.04 0.03 0.06 0.06 0.04 0.04

PW

Range 1.80–2.12 1.93–2.13 2.02–2.62 2.12–2.57 2.24–2.52 2.24–2.67Mean 2.02 2.03 2.31 2.32 2.40 2.47SD 0.08 0.07 0.11 0.11 0.07 0.11

BH

Range 1.81–2.00 1.88–2.03 1.90–2.33 1.88–2.26 2.05–2.30 2.10–2.45Mean 1.90 1.93 2.08 2.13 2.15 2.26SD 0.04 0.06 0.08 0.08 0.06 0.08

EL

Range 2.97–3.44 3.18–3.57 3.15–4.00 3.14–4.18 3.39–4.12 3.45–4.18Mean 3.25 3.39 3.55 3.64 3.68 3.85SD 0.13 0.13 0.20 0.22 0.16 0.18

EH

Range 1.45–1.64 1.46–1.64 1.44–1.87 1.51–1.94 1.57–1.96 1.67–2.02Mean 1.54 1.56 1.70 1.73 1.79 1.83SD 0.06 0.06 0.08 0.08 0.09 0.09

EW

Range 2.14–2.38 2.12–2.31 2.24–2.94 2.38–2.97 2.52–2.96 2.50–3.03Mean 2.25 2.23 2.58 2.59 2.73 2.82SD 0.05 0.06 0.13 0.13 0.11 0.13

EPH

Range 0.10–0.17 0.10–0.17 0.10–0.52 0.10–0.62 0.26–0.36 0.27–0.39Mean 0.12 0.13 0.29 0.36 0.31 0.35SD 0.02 0.02 0.10 0.15 0.02 0.03

PTL

Range 0.70–0.80 0.70–0.81 0.76–1.02 0.76–1.02 0.79–0.93 0.79–0.93Mean 0.75 0.74 0.84 0.84 0.83 0.85SD 0.03 0.03 0.05 0.05 0.03 0.03

PTW

Range 0.26–0.30 0.21–0.26 0.29–0.39 0.25–0.33 0.31–0.36 0.26–0.39Mean 0.28 0.23 0.34 0.28 0.33 0.29SD 0.01 0.01 0.02 0.02 0.01 0.02

PFL

Range 1.07–1.19 1.07–1.17 1.15–1.50 1.14–1.46 1.28–1.40 1.22–1.44Mean 1.12 1.11 1.30 1.28 1.32 1.34SD 0.03 0.03 0.07 0.07 0.03 0.05


Table 5. Continued.


Malen ¼ 15

Femalen ¼ 14

Male(n ¼ 78)

Female(n ¼ 62)

Male(n ¼ 22)

Female(n ¼ 26)

PFW

Range 0.31–0.36 0.31–0.38 0.33–0.43 0.36–0.43 0.36–0.40 0.36–0.42Mean 0.35 0.34 0.38 0.39 0.38 0.39SD 0.01 0.02 0.02 0.02 0.01 0.02

HTL

Range 0.61–0.71 0.64–0.70 0.69–0.89 0.71–0.89 0.73–0.84 0.74–0.90Mean 0.66 0.67 0.79 0.82 0.80 0.83SD 0.03 0.02 0.04 0.05 0.03 0.04

HTW

Range 0.45–0.49 0.45–0.50 0.48–0.64 0.50–0.64 0.52–0.62 0.52–0.64Mean 0.47 0.47 0.55 0.55 0.56 0.57SD 0.01 0.02 0.03 0.03 0.03 0.03

HFL

Range 0.63–0.71 0.62–0.71 0.69–0.91 0.71–0.88 0.76–0.85 0.74–0.90Mean 0.67 0.67 0.77 0.79 0.81 0.84SD 0.02 0.03 0.04 0.04 0.02 0.04

HFW

Range 0.37–0.41 0.34–0.44 0.41–0.50 0.38–0.50 0.41–0.47 0.43–0.50Mean 0.39 0.39 0.45 0.46 0.44 0.46SD 0.01 0.02 0.02 0.03 0.02 0.02

MTL

Range 0.40–0.46 0.45–0.60 0.48–0.60Mean 0.42 0.54 0.53SD 0.02 0.03 0.03

MTW

Range 0.22–0.26 0.24–0.36 0.26–0.31Mean 0.24 0.30 0.27SD 0.01 0.03 0.02

SBL

Range 4.49–5.06 4.68–5.09 4.78–5.89 4.69–5.98 4.99–5.76 5.04–5.97Mean 4.78 4.89 5.26 5.34 5.34 5.54SD 0.16 0.16 0.26 0.30 0.18 0.22

SBL/BH

Range 2.42–2.16 2.46–2.68 2.39–2.73 2.25–2.97 2.43–2.62 2.34–2.58Mean 2.52 2.53 2.53 2.51 2.49 2.46SD 0.06 0.06 0.09 0.11 0.05 0.07

SBL/EW

Range 2.01–2.20 2.08–2.23 1.93–2.28 1.89–2.32 1.89–2.09 1.88–2.16Mean 2.13 2.18 2.03 2.06 1.95 1.96SD 0.05 0.04 0.07 0.08 0.04 0.06

EL/EW

Range 1.33–1.52 1.41–1.55 1.28–1.51 1.27–1.63 1.30–1.42 1.30–1.53Mean 1.44 1.50 1.38 1.40 1.34 1.36SD 0.05 0.04 0.06 0.06 0.03 0.05


A79-9 [typed]/ Gyretes sinuatus Lec. Det. Sanderson 1983/ Gyretes torosus Babin,Det. J.J. Babin 2002/ Gyretes torosus Babin 2002 Holotype [red rectangular label]. Thedorsal and ventral surfaces are relatively free of dirt. Body black. Penultimate tergitewithout midcaudal tooth Aedeagus and parameres glued to a rectangular point pinnedbeneath specimen.

The allotype is a female specimen (USNM) glued to a point with the followinglabels: ARIZ. Yavapai Co., Convergence Oak Cr. and Verde R. 10, July 10 1979.M.W. Sanderson UV light trap. A79-9 [typed]/ Gyretes sinuatus Lec. Det. Sanderson1983/ Gyretes torosus Babin, Det. J.J. Babin 2002/ Gyretes torosus Babin 2002Allotype [red rectangular label]. Body black. The dorsal and ventral surfaces arerelatively free of dirt. Penultimate tergite without midcaudal tooth. Last threeabdominal segments slightly dislodged to the right.Etymology. The specific name ‘torosus’ is chosen to reflect the relatively larger size

and and the more brawny shape of this species.Diagnosis. This species is relatively robust, having a wider body than G. sinuatus

and G. iricolor and is not as attenuated as G. iricolor. At 403 pronotum with evidentmicropunctures but microreticulation not distinct. Midcaudal tooth on the penultimatetergite lacking. Body outline ovate in lateral view. Female elytral apex does not extendalong midline, but may be slightly produced (Figs. 21, 23). Epipleura orange to dark-brown, generally darker than G. iricolor.

Description. Microsculpture and punctation. Pronotal microreticulation transverselyelongated, not distinct at a magnification of 403. Microreticulation on the female elytral apexnot distinct. Micropunctation evident on pronotum and elytra. Measurements (Table 5).

Table 5. Continued.


Malen ¼ 15

Femalen ¼ 14

Male(n ¼ 78)

Female(n ¼ 62)

Male(n ¼ 22)

Female(n ¼ 26)

PTL/PTW

Range 2.39–2.91 2.93–3.56 2.19–2.80 2.58–3.36 2.24–2.69 2.30–3.14Mean 2.69 3.17 2.48 2.96 2.50 2.91SD 0.16 0.20 0.15 0.15 0.11 0.17

PW/PL

Range 2.23–2.69 2.44–2.72 2.24–2.72 2.31–2.87 2.48–2.80 2.39–3.03Mean 2.42 2.55 2.45 2.52 2.62 2.68SD 0.11 0.09 0.11 0.10 0.09 0.15

HW/HL

Range 1.96–2.22 1.96–2.14 1.98–2.42 1.93–2.47 2.13–2.40 2.11–2.40Mean 2.08 2.04 2.16 2.18 2.25 2.26SD 0.07 0.06 0.09 0.10 0.07 0.08

EW/PW

Range 1.06–1.16 1.09–1.14 1.00–1.17 1.02–1.17 1.10–1.18 1.02–1.23Mean 1.11 1.11 1.12 1.12 1.13 1.15SD 0.02 0.01 0.02 0.03 0.02 0.04

PW/HW

Range 1.25–1.48 1.33–1.41 1.36–1.48 1.32–1.47 1.42–1.47 1.34–1.56Mean 1.38 1.38 1.41 1.40 1.44 1.43SD 0.05 0.02 0.02 0.03 0.01 0.05


Pronotum 1.3–1.6 times broader than head. Elytra 1.0–1.2 times broader than pronotum.Standardized body length 1.9–2.2 times greater than body width. Elytral pubescence broader thanG. iricolor (0.3–0.4 mm). Female pubescent band is reduced to 2–4 hairs at elytral apex. Maleprotibia more strongly widened distally than G. iricolor, 2.2–2.7 times longer than wide.

Remarks. Body outline ovate in lateral view. Penultimate tergite may be sinuousbut lacks a distinct midcaudal tooth. Female elytral apex at most slightly produced inlateral perspective.Distribution. Arizona to Texas.Material Examined. One hundred and ten specimens with the following label data:

ARIZONA: Guadalupe Canyon, SE Arizona, at light, 31.VII.1975, coll. Scott McCleve(6, UAIC); Peloncillo Mtns., 33 mi. E. Douglas, at light, 17.VII.1973, coll. S. McCleve (3,UAIC); San Bernardino Ranch, SE Arizona, at light, 14.VII.1975, coll. S. McCleve (1,UAIC); Guadalupe Canyon, Cochise Co., at light, 2.VIII.1977, coll. S. McCleve (1,UAIC); Guadalupe Canyon, Cochise Co., 8.VIII.1983, coll. C.A. Olson (1, UAIC);Coconino Co., Oak Cr. Cmpgd, Red Rock X-ing, 14.VII.81, coll. J.C. Burne (3, UAIC);Kocineo Co.(Presumed to be Coconino Co)., 8.2.62, coll. Don Rich (4, CISC); E. VerdeR., Gila Co., 3 mi. N. Payson, Hwy 87, 20.VI.1977, coll. Folkerts and field class (2,UAIC); Salt River Canyon, Gila Co., 16.IV.1969, coll. H.M. Ohlendorf (1, TAMU);Greenlee Co., Big Lue Mountain, UV, 16.VII.79, coll. Olson, Sailowitz (1, UAIC);Navajo Co., 1 mi. E. Lakeside, at light, 2,090 m, 12.VIII.1978, coll. Scott McCleve (1,UAIC); Yavapai Co., Rd. 120, S. Village Oak Cr., UV light trap, 3–4.VIII.1983, coll.M.W. Sanderson (1, USNM); Oak Cr., Deer Pass Crossing, Yavapai Co., SW Sedona,11.V.1977, coll. M.W. Sanderson (3, USNM); Oak Cr., Deer Pass Crossing, Yavapai Co.,UV light trap, 15.VII.1977, coll. M.W. Sanderson (1, USNM); Oak Cr., Cornville,

Fig. 25. Known distribution of Gyretes iricolor in America north of Mexico.


Yavapai Co., UV light trap, 10.VII.1979, coll. M.W. Sanderson (2, USNM); Oak Cr.,Cornville, Yavapai Co., at UV light trap, 8.VIII.1978, coll. M.W. Sanderson (1, USNM);Oak Cr., Baldwins Crossing, Yavapai Co., UV light trap, 19.VII.1977, coll. M.W.Sanderson (3, USNM); Oak Cr., Yavapai Co., Red Rock, S. Sedona, 4.VIII.1983, coll.C.B. Barr (3, CISC; 5, LSAM); Yavapai Co., convergence Oak Cr. and Verde R.,9.VI.1977, coll. M.W. Sanderson (1, USNM); Yavapai Co., convergence Oak Cr. andVerde R., UV light trap, 10.VII.1979, coll. M.W. Sanderson (6, USNM); Camp Verde,Yavapai Co., 28.VII.1962, coll. W.W. Boyle, M.A. Goodrich (1, FEMP); Verde R.,Yavapai Co., Campe Verde, UV light trap, 10.VII.1980, coll. M.W. Sanderson (3,USNM); Camp Verde, Yavapai Co., black light trap, 15.VII.1969, coll. A. and B. Hilton(7, INHS); Yavapai Co., 7.5 mi. ESE Camp Verde, W. Clear Cr. Cp., 3,500 ft, black light,11.VII.1968, coll. G.W Forister (1, INHS); Verde R., Cottonwood, Yavapai Co., UV lighttrap, 19–20.VII.1981, coll. M.W. Sanderson (3, USNM); Red Tank Draw, Yavapai Co.,1.5 mi. E. jct 17–179 on rd. 645 to Beaver Creek, UV light trap, 10–11.VII.1982, coll.M.W. Sanderson (7, USNM); Beaver Cr., Yavapai Co., nr Montezuma Well, 14.VI.1985,coll. M.V. Sanderson (8, ROMC); Yavapai Co., 7 mi. S. Sedona, Village Oak Cr., at light,25–26.VII.1982, coll. M.W. Sanderson (10, USNM); Yavapai Co., 7 mi. S. Sedona,Village Oak Cr., Porch light over funnel, 2–15.VIII.1982, coll. M.W. Sanderson (1,USNM); Yavapai Co., Coconino Natl. For., Clear Cr. Campgrd, at black light,29.VII.1983, coll. C.B. Barr (1, CISC; 2, LSAM); Yavapai Co., Rd. 120, 10 mi. S.Sedona, 1 mi. W., UV light trap, 5–9.VIII.1982, coll. M.W. Sanderson (2, USNM).NEWMEXICO: Carlsbad (1, USNM); E. Fort Gila R., Grant Co., Gila N.P., E. off Hwy 15,7.VIII.1987, coll. C.B. and J.E. Barr (1, CISC; 2, LSAM); E. Fort Gila R., Grant Co.,27.VIII.1934, coll. Carl J. Drake (1, CISC; 1, LSAM). TEXAS: (1, CASC; 2, FMNH; 1

Fig. 26. Known distribution of Gyretes torosus new species in America north of Mexico.


INHS); Ottine Palmetto State Park, 12–13.VIII.1963, coll. P.J. Spangler (3, USNM); SanMarcos R., Gonzales Co., Palmetto State Park, 31.V.1983, coll. C.B. Barr (1, CISC).

Discussion

Taxonomic recognition of North American members of the genus Gyretes hasproven to be very problematic owing to their overall similarity. Indeed, in the mostrecent attempt aimed at identifying the species of this genus, Walls (1974) was unableto identify a number of specimens due to overlapping measurements and intermediatecharacter states occurring with the character system used.

Despite detailed analyses of external features, it became obvious that no uni- orbidimensional approach could help in discriminating these species. Characters used inpast studies, such as the thickness of the pubescence and shape of the elytral apex, showa continuum, often with an east-west pattern, proving a discrete approach to be lessuseful than previously believed (Walls 1974). Morphologically, responses may occur ina multidimensional fashion, rather than as a change in a single character (Foottit andSorensen 1992). Species may overlap when characters are studied individually, butthey may become distinct entities when many characters are considered jointly.A multivariate approach was therefore favoured for this study.

Several measurements were made to characterize the form of the species studied. PCAextracted three components useful in explaining the total variance between the specimens(82.6% for males; 82.9% for females). The first component was a general size component(Table 3) for both males (37.4% total variance explained, eigenvalue¼10.5) and females(43.4% total variance explained, eigenvalue¼11.3). The second component was highlyloaded by pubescence for females (25.6% total variance explained, eigenvalue¼6.6, seeTable 3 for eigenvector coefficients) and pubescence with prolegs for males (31.1% totalvariance explained, eigenvalue¼8.7, see Table 3 for eigenvector coefficients). The thirdcomponent was highly loaded by clypeal length (Table 3) for both males and females andexplained 14.1% of the total variance for males (eigenvalue¼3.9) and 13.9% of the totalvariance for females (eigenvalue¼ 3.6) (Tables 2, 3).

Ordination plots of the first two components (which together explained 68.5% of thetotal variance for males and 69.0% for females) demonstrated the ability of the PCA toseparate the specimens into three subgroups (¼ centroids). The ordination plot resultedin a slight horseshoe pattern in both male and female specimens. A stronger arch issometimes viewed as a cause of concern for a PCA as it reveals a polynomial design inthe data (Pimentel 1992; Podani 2000). A Detrended Correspondence Analysis (DCA)has been developed to remove such an arch in multivariate analyses, however, is notnecessary or even recommended by some authors (Podani 2000). Indeed, with this typeof taxonomic study, a slight polynomial trend is of no great concern and can almost beexpected from morphological data. This is due to the nature of such a study, ‘‘when onetaxon has a body part longer than wide, another the opposite, then the relationshipamong the taxa is nonlinear’’ (Pimentel 1992).

Centroid 1 was associated with specimens showing a southeastern distribution (Figs.10, 11). Specimens within this subgroup shared a number of qualitative features such asan angular body outline, lack of a midcaudal tooth on the penultimate tergite, pronotalmicroreticulation not distinct at a magnification of 403 and small body size. Centroid 1was defined a posteriori as G. iricolor.

Similarly, the syntypes of G. sinuatus and G. compressus grouped along withspecimens associated with Centroid 2 (Figs. 10, 11). This group was qualitativelycharacterized by a variable body outline, presence of a midcaudal tooth on thepenultimate tergite, pronotal microreticulation that is distinct at a magnification of 403and a variable body size. The fact that both syntypes share qualitative features with other


specimens associated with this second group and cluster together in the multivariatespace strongly suggests that G. sinuatus and G. compressus are the same species. Giventhat G. compressus was described posteriorly to G. sinuatus, it is hereby proposed thatthe former species name is a junior subjective synonym of G. sinuatus. This conclusion isin accord with some previous works by Ochs (1949), Poole and Gentili (1996) andRegimbart (1883). The species name G. californicus must also be postulated to bea junior subjective synonym of G. sinuatus. The holotype of G. californicus could not befound for this study, despite efforts to trace the specimen. It was reportedly a singlefemale specimen that could not be distinguished fromG. sinuatus in its description (Ochs1949; Leech and Chandler 1963; Walls 1974). The examination of this type would be ofthe utmost interest in order to know if this name could be applied to G. torosus newlydescribed in this paper. The fact that the type locality of G. californicus (California) lieswithin the distribution of G. sinuatus as defined in this study, however, is seen as anadditional argument to put this name under G. sinuatus.

An interesting finding in this study was the presence of a third species grouprepresented by Centroid 3 (Figs. 10, 11). This centroid is almost equidistant from bothCentroids 1 and 2. Specimens included in this group were found to be characterized by:ovate body outline, lack of a midcaudal tooth on the penultimate tergite, pronotalmicroreticulation not distinct at a magnification of 403 and a larger, more robust bodyshape. Assuming that Centroids 1 and 2 refer to G. iricolor and G. sinuatusrespectively, and that both G. compressus and G. californicus are junior synonyms ofG. sinuatus, Centroid 3 should refer to G. torosus new species. At the moment G.torosus is distributed from southern Arizona to Texas, along the Mexican border. Sucha distribution may suggest that this species is found in Mexico. We examined someMexican species (G. leionotus Aube, G. boucardi Sharp, G. minor Regimbart, andG. minor laevipennis Ochs). Variation in the shape of the body outline and pattern ofmicroreticulation indicate that specimens included in Centroid 3 could not be any ofthese species. This leaves three remaining species in Mexico: G. acutangulus Sharp, G.dampfi Ochs, and G. mexicanus Regimbart (R. A. Perez pers. comm.) as well as thepossibility of G. sinuatus, as this species was recorded from Central America by Ochs(1949). The descriptions provided in this paper, however, could not help at identifyingCentroid 3. Central American Gyretes are in great need of revision and accordingly thekey of Ochs (1949) seems outdated. Until a thorough worldwide revision of this genusis done, it seems more appropriate to refer to specimens of Centroid 3 as G. torosus.

At the moment, the genus Gyretes has a transcontinental distribution within theUnited States, ranging mostly along the southern states and northeast up to the 408Nlatitude. Compared to the other North American species, Gyretes sinuatus shows themore extensive distribution ranging from the extreme southwest to the northeast (Fig.24). As a result of this study, Arizona, Arkansas, Kansas, Oklahoma and Virginia areseen as new state records since the last study of this genus (Walls 1974).

At the moment, the species G. iricolor is found to be restricted to the southeasternUnited States (Alabama and Florida). Folkerts and Donavan (1973) also recorded thisspecies in Mississippi. It seems likely that this state could be part of the distribution ofG. iricolor due to its proximity to Alabama but as no specimens of G. iricolor fromMississippi were available for this study, this observation cannot be confirmed.

Finally, Gyretes torosus shows a range of distribution in southwestern United Statesfrom Arizona to Texas (Fig. 26).

Acknowledgments

We thank the individuals and institutions mentioned in the ‘‘Specimens’’ section formaking material available to us for study. Anders Nilsson (University of Umea,


Sweden) is acknowledged for his critical review of the M. Sc. thesis from which thispaper was prepared. YA was supported by a Natural Sciences and EngineeringResearch Council of Canada Research grant.

Literature Cited

Ferkinhoff, W. D., and R. W. Gundersen. 1983. A key to the whirligig beetles of Minnesota andadjacent states and Canadian provinces (Coleoptera: Gyrinidae). Scientific Publications ofthe Science Museum of Minnesota 5(3):1–53.

Folkerts, G. W. 1979. Spanglerogyrus albiventris, a primitive new genus and species ofGyrinidae (Coleoptera) from Alabama. The Coleopterists Bulletin 33:1–8.

Folkerts, G. W., and L. A. Donavan. 1973. Resting sites of stream-dwelling gyrinids(Coleoptera). Entomological News 84:198–201.

Foottit, R. G., and J. T. Sorensen. 1992. Ordination methods: their contrast to clustering andcladistic techniques [pp. 1–10]. In: Ordination in the study of morphology, evolutionand systematics of insects: applications and quantitative genetic rationals (J. T. Sorensenand R. Foottit, editors). Elsevier Science Publishing Inc., New York.

LeConte, J. L. 1852. Descriptions of new species of Coleoptera from California. Annals of theLyceum of Natural History of New York 1(1):125–216.

LeConte, J. L. 1863. New species of North American Coleoptera, part I. SmithsonianMiscellaneous Collections 6(167):1–177.

LeConte, J. L. 1868. The Gyrinidae of America, North Mexico. Proceedings of the Academy ofNatural Sciences of Philadelphia 20:365–373.

Leech, H. B., and H. G. Chandler. 1963. Aquatic Coleoptera [pp. 293–371]. In: (R. L. Usinger,editor) 1963. Aquatic Insects of California with Keys to North American Genera andCalifornia Species. University of California Press, Berkeley.

McCleve, S. 1978. Gyretes sinuatus LeConte in Arizona (Coleoptera: Gyrinidae). TheColeopterists Bulletin 32(3):257.

Meinwald, J., T. Eisner, and K. Opheim. 1972. Gyrinidal: a sesquiterpenoid aldehyde from thedefensive glands of gyrinid beetles. Proceedings of the National Academy of SciencesUSA 69(5):1208–1210.

Ochs, G. 1924. On the West Indian Gyrinidae and a new species of Gyretes from Northern Brazil.American Museum Novitates 125:1–8.

Ochs, G. 1929. Bestimmungstabelle de Gyrinidengattung Gyretes Brulle. KoleopterologischeRundschau 15(2/3):62–92.

Ochs, G. 1949. A revision of the Gyrinoidea of Central America (Col.) Revista de Entomologia(Brazil) 20(1/3):253–300.

Oygur, S., and D. Wolfe. 1991. The classification, distribution and phylogeny of North American(North of Mexico) species of Gyrinus Muller (Coleoptera: Gyrinidae). Bulletin of theAmerican Museum of Natural History 207:1–97.

Pimentel, R. A. 1992. An introduction to ordination, Principal Components Analysis andDiscriminant Analysis [pp. 11–28]. In: Ordination in the study of morphology, evolutionand systematics of insects: applications and quantitative genetic rationals (J. T. Sorensonand R. Foottit, editors). Elsevier Science Publishing Inc., New York.

Podani, J. 2000. Introduction to the exploration of multivariate biological data. BackhuysPublishers, Leiden.

Poole, R. W., and P. Gentili. 1996. Nomina insecta nearctica: a checklist of the insects of NorthAmerica. Vol 1: Coleoptera, Strepsiptera. Entomological Information Services. Rockville,Maryland.

R�gimbart, M. 1883. Essai monographique de la famille des Gyrinidae: 3e Parti. Annales de laSociete Entomologique de France 6(3):381–482.

R�gimbart, M. 1907. 3e Supplement de la famille des Gyrinidae. Annales de la SocieteEntomologique de France. 6(76):137–245.

Roughley, R. E. 2001. Gyrinidae Latreille, 1810 [pp. 133–137]. In: American beetles Volume 1;Archostemata, Myxophaga, Adephaga, Polyphaga: Staphyliniformia (R. H. Arnett, Jr. andM. C. Thomas, editors). CRC Press, Washington, D.C.

SPSS Inc. 1988. SPSS-X� User’s guide. 3rd ed. SPSS Inc., Illinois.


Steiner, W. E., Jr., and J. J. Anderson. 1981. Notes on the natural history of Spanglerogyrusalbiventris Folkerts, with a new distribution record (Coleoptera: Gyrinidae). Pan-Pacific

Entomologist 57(1):124–132.Walls, J. G. 1974. Distribution and recognition of United States whirligig beetles of the genus

Gyretes (Coleoptera: Gyrinidae). Studies in Arthropoda 1(1):1–10.Young, F. N. 1947. A new species of Gyretes from western Florida. Florida Entomologist 30(3):

31–33.Young, F. N. 1954. Water beetles of Florida. University of Florida Press.

(Received 2 May 2003; accepted 5 November 2003. Publication date 24 January 2005.)

The Coleopterists Bulletin, 58(4):567–568. 2004.

SCIENTIFIC NOTE

Occurence and Conservation Status of the Milkweed Beetle Tetraopes texanus Horn(Coleoptera: Cerambycidae) in Arkansas

The cerambycid genus Tetraopes Dalman is represented by 13 species in the United States andsouthern Canada (Chemsak 1963). Species of Tetraopes are milkweed specialists (AsclepiasLinnaeus), with adults feeding on leaves and flowers and larvae feeding within roots. Hostspecificity is high within the genus, with Tetraopes species exhibiting preferences for specificmilkweed species (Farrell and Mitter 1998).

Individuals of Tetraopes texanus Horn were recently collected from two distinct regions ofArkansas. These collections establish a new state record and extend the known range of thisspecies. The primary distribution of T. texanus was described as occurring from Oklahoma toTexas and into northern Mexico (Chemsak 1963; Linsley and Chemsak 1995). However, Rice(1988) and MacRae (1993) published records that extended the distribution of this species intoMissouri, and Schiefer (1998) discovered disjunct populations of T. texanus in Mississippi andAlabama. Recently, Huber and Wright (2002) reported this species in Kansas.

New Records. U.S.A., Arkansas: Franklin County, H.E. Flanagan Prairie Natural Area, May19, 2003, M.D. Warriner (6 adults, deposited University of Arkansas Arthropod Museum).Hempstead County, Grandview Wildlife Management Area, June 5, 2003, M.D. Warriner (8adults, deposited University of Arkansas Arthropod Museum).

The Franklin County collections are from a tallgrass prairie remnant approximately 120 mileseast of the nearest reported occurrences in Oklahoma. Collections from Hempstead County werefrom blackland prairie habitat approximately 145 miles east of the nearest reported occurrence ofT. texanus in Texas. Both Arkansas records are separated from one another by 110 miles anda significant physical barrier, the Ouachita Mountains.

Yanega (1996) listed the host plant of T. texanus as A. viridiflora Rafinesque. In Missouri,specimens of T. texanus were also recorded as being associated with A. viridiflora (Rice 1988;MacRae 1993). Huber and Wright (2002) obtained specimens from A. syriaca Linnaeus. InMississippi and Alabama, Schiefer (1998) noted that the probable host plant for T. texanus in thosestates was A. viridis Walter. All specimens in Arkansas were observed on and taken from A.viridis. This plant is the likely host for this species in Arkansas as well.

Known Arkansas populations of T. texanus are strongly associated with tallgrass and blacklandprairie remnants hosting relatively large patches of A. viridis. Association with prairie habitat hasbeen noted by Rice (1988) in Missouri, Schiefer (1998) in Mississippi/Alabama, and Huber andWright (2002) in Kansas. Tremendous losses of prairie have occurred across the Great Plains andin Arkansas as a result of human activity (Noss et al. 1995). What little prairie remains in Arkansasis highly fragmented and often isolated from other prairie habitat by considerable distances.Studies examining the movements of Tetraopes species have shown that individuals moveinfrequently between host plant patches unless patches are large, close, and host plant density ishigh (Lawrence 1988). Once in dispersal mode, these beetles also appear to be poor at relocating


host plants (Lawrence 1988). Consequently, increased destruction and degradation of existingprairie habitat containing suitable host plant resources could have a negative impact on thesustainability of Tetraopes populations (Rice 1988). Tetraopes species known to occur inassociation with fragmented habitats should be considered of some conservation concern.

Literature Cited

Chemsak, J. A. 1963. Taxonomy and bionomics of the genus Tetraopes (Cerambycidae:Coleoptera). University of California Publications in Entomology, Volume 30, No. 1,University of California Press, Berkeley. 89 pp.

Farrell, B. D., C. Mitter. 1998. Might Tetraopes (Cerambycidae) and Asclepias (Asclepiadaceae)have coevolved? Biological Journal of the Linnean Society 63:553–577.

Huber, R. L., V. F. Wright. 2002. First Kansas record for Tetraopes texanus (Coleoptera:Cerambycidae). Journal of the Kansas Entomological Society 75:341.

Lawrence, W. S. 1988. Movement ecology of the red milkweed beetle in relation to populationsize and structure. Journal of Animal Ecology 57:1–35.

Linsley, E. G., J. A. Chemsak. 1995. The Cerambycidae of North America, Part VII, No. 2:taxonomy and classification of the subfamily Lamiinae, tribes Acanthocinini throughHemilophini. Univ. Calif. Publ. Entomol., Vol. 114. University of California Press, Berkeley.292 pp.

MacRae, T. C. 1993. Annotated checklist of the longhorned beetles (Coleoptera: Cerambycidaeand Disteniidae) occurring in Missouri. Insecta Mundi 7:223–252.

Noss, R. F., E. T. LaRoeIII, J. M. Scott. 1995. Endangered ecosystems of the United States:a preliminary assessment of loss and degradation. U.S. Department of the Interior, NationalBiological Service, Biological Report 28. 58 pp.

Rice, M. R. 1988. Natural history observations on Tetraopes and other Cerambycidae(Coleoptera) from the Great Plains ecosystem. Journal of the Kansas EntomologicalSociety 61:412–419.

Schiefer, T. L. 1998. Disjunct distribution of Cerambycidae (Coleoptera) in the black belt prairieand Jackson prairie in Mississippi and Alabama. Coleopterists Bulletin 52:278–284.

Yanega, D. 1996. Field guide to northeastern longhorned beetles. Illinois Natural History Survey,Manual 6. 184 pp.

Michael D. Warriner, Arkansas Natural Heritage Commission, 1500 Tower Building, 323Center St., Little Rock, AR 72201-.S.A. [email protected].

(Received 14 October 2003; accepted 28 June 2004. Publication date 24 January 2005.)


taxonomic revision of genus gyretes brullé (coleoptera: gyrinidae) from america north of mexico

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