introdUCtion

the present work is part of a study on the Cactaceae ofsouthern Peru, which has been running for several years. as abackground, several studies have already been carried out onthe cactaceae of the arequipa region, especially in the andeanhighlands, but very few investigations have been made on thecactaceas that live in the hills, valleys and ravines of the coastof arequipa. in the last five years studies began in the coast ofarequipa, especially in arid hills, with rather scarce resultsbecause the cacti of these areas were always in a vegetativestate. all winters and springs these lomas were visited, but theresults were always the same. However from June 2013 todecember 2014 in the coast of the province of islay andCamaná intense rains began on the hills and also in the ravinesbetween 800 and 1200 m a.s.l. in the completely arid pampas.therefore, while rains persisted, up to 2014, important excur-sions and large plant collections were made between 200 and1050 m a.s.l.. other explorations were later extended above1050 m a.s.l., especially in the pampas of the toro gully, andsome areas that have been given in concession for irrigation.during the spring time the cacti were found in flower. thisallowed to carry out a bio-systematic study of the cactáceasand beside to verifie their state of conservation.

in the province of Camaná above 500 m a.s.l. Cleistocactus

sextonianus, Haageocereus decumbens, occur. this paperdeals with the results of some studies carried out on Islaya thatin such area occurs under 500 m a.s.l..

this genus was described in 1934 by BaCKeBerg, whichreferred its name to the province of islay in the arequiparegion. the species formerly included there were afterwards

in turn transferred to several other genera such asEchinocactus, Malacocarpus, Neoporteria and then toEriosyce. Besides, all the former species of Islaya were inclu-ded by KatterMan (1994) in a single specific taxon, Eriosyce

islayensis (Forster) Katterman together with 10 other Chileangenera. the same treatment was made by anderson (2001).nevertheless, on the basis of a comprehensive anatomical andsystematic study of the genus Eriosyce (including the Peruvianspecies), nyFFeler & eggli (1997) stated that the populationsoccurring along the coasts of Peru do not belong to Eriosyce,but to another genus. taking into account this work, ostolaza

(2014) referred such populations to Islaya Backeb. and propo-sed a larger revision of this genus, especially for the Peruvianpopulations. these studies are still in progress from both thebio-systematic and conservation points of view.

according to BaCKeBerg (1958-1962) and ritter (1964)the genus Islaya includes globular to shortly cylindrical plantswith very woolly apex, yellow, apical small flowers, shortlyconical floral tube with wool and bristles; fruit red, elongatedwith hairs and floral remains, hollow at the base, with the blackseeds in a carpelar dehiscent sac at its base.

only two Islaya species and one subspecies were so farknown from Peru: Islaya islayensis (Forster) Backeb. subspislayensis, Islaya islayensis subsp grandis (rauh & Backeb.)g. Charles and Islaya omasensis ostolaza et Mischler that hasbeen described very recently (ostolaza 2014). in addition, anew endemic species is here described and called Islaya cama-

naensis Cáceres, with reference to the name of the Province ofCamaná where it occurs in the department of arequipa.

Quad. Bot. Ambientale Appl., 30 (2019): 33-39.

Taxonomic studies on the genus Islaya (Cactaceae): Islaya camanaensis, a newendemic species from Arequipa region (Peru)

†F. CáCeres de Baldárrago1, F.M. raiMondo2, i. PoMa2 & P. Mazzola21Herbarium arequipense HUsa. laboratorio de Botánica. dpto. de Biología, Facultad de Ciencias Biológicas. Universidadnacional de san agustín. arequipa, Peru. 2PLANTA/Centro mediterraneo di ricerca, documentazione e Formazione, Via serraglio Vecchio 28 i - 90123 Palermo.raimondo@centroplantapalermo.org

aBstraCt. – in the context of a research project on cactaceae family of the southern region of Peru, a population of the genus Islaya wasparticularly critical. the taxonomic study carried allowed to describe a new species called Islaya camanaensis whith reference to theprovince of Camaná where it occurs between 900 and 1050 m a.s.l.. such species shows clear taxonomic differences from the other Islaya

species occurring in Peru, as far as root and stem; ribs, areolas, lilac flowers, fruits and seeds are concerned. the species, which is soli-tary in its habitat, blooms in september and bears fruits in november december. an average of 7 individuals in 100 m2 were evaluatedin a transect of 50 km. its main threat are the roads and concession in areas that have been delivered to expand agriculture and housing.

Key words: succulent plants, endemic flora, Perù, Camaná province.

Pubblicato online: 24/04/2020http://www.centroplantapalermo.org/

taxonoMy

Islaya camanaensis Cáceres sp. nov. (Figs. 1, 2 & 3)

Diagnosis

small plant 5-10 cm high. it bears 18 straight or spiraleduniform ribs; oval areolas margined by two rows of shortspines; spines 8-10, 1-2 mm long; central spines 4, 2-3 mmlong, greyish green. Parenchyma and inner medulla reddish,about 2 cm. Flowers with calyx-like tepals dark lilac; corol-la-like tepals lilac purple to light lilac. staminal filamentthin; anthers intense yellow. ovary rounded to short ovoid;short cylindrical style 10-12×2.5 mm. stigmas 10-12, wide,oblanceolate, whitish, 4-5×1.2. small fruits 0.5-1 cm, cove-red by abundant whitish wool with persistent and abundantred bristles, and floral coverings. seeds 6-10 kidney-shaped;outer coat blackish and shiny. the new species differs fromboth Islaya islayensis (Forster) Backeb. and Islaya divari-

catiflora ritter.

Type

Perú. departamento de arequipa. Pampas de samuelPastor. Provincia de Camaná. 900 m a.s.l. 14 de octubre del2013. Cáceres & Baldárrago, nro 7323 (Holo, HUsa).

Description

small cactus 5-10 cm high, half or almost all buried,rounded to ovoid, compressed apically (Fig. 1), green-gra-yish. roots dichotomously branched, 15 cm long (Fig. 3a).stem: succulent, ovoid 5-10×(4)-7 cm. areolas 3-4 mm,oval with two marginal rows of short spines; 8-10 short spi-nes 1-2 mm long; 4 central spines 2-3 mm long. Very densewoolly reddish bristles on the apical part of the stem; gra-yish green colour. Parenchyma reddish; medulla 2 cm indiameter, reddish. ribs 16-18 straight or spirally twisted;ribs 0.5 cm distant and hight, parenchyma reddish, corticalmedulla 2 cm, reddish. spines 10-12 in two series, the mar-ginal 6-7 almost homogeneous 5 mm long at the border of

the areola and 4-5 central spines 5-7 mm long, extendedtowards the sides. Flowers sessile with diploclamide peri-gon, with numerous dark lilac to purple tepals 3.8-4×2.5-2.8 cm in the floral tube and 3.5 cm in the anthesis. tepalsintense pale to dark lilac, not reddisch. dense woollyhypanthium, covering up to the half of tepals, 1.2×0.8 inthe middle and 0.5-1×1.5 cm in the apical part. Bractsslightly subulate, 1.5-3 mm with areolas of 2 mm and abun-dant whitish wool, that remains on the fruit until after ripe;bristles reddish, abundant at the base of tepals. Calyx-liketepals subulate, dark lilac 3-5 1.5-2.5 mm in 2-3 series,hardly distinguishable by dense wool. Corolla-like tepalsnumerous, obovate with acute apex, slightly mucronatewith a dark central stain along the tepalo, 2.8-3.2×0.6 cm,light to dark lilac, not reddish. stamens numerous; fila-ments cylindrical shorter than the stigma, withish; anthersdistichous intense yellow, 1 × 1-2 mm. ovary rounded toovoid, ovules ovoid clear cylindrical; style 10-12×2.5 mm;stigma 10-12 numerous 4-5×1.2 mm, whitish. Fruit:slightly rounded ovoid 0.8-1 cm, dark lilac; areolas 1 mm,woolly, dehiscent by the base; cover by numerous whitishhairs and dense red bristles remaining until after the fruit isripe. seeds 6-10, reniform 2×1.5 mm; testa shiny black,hilum whitish.

Habitat

the species occurs only in the loose and marlestone soils ofthe pampas in sandy, crusty, desertic soils from 900 to 1050 ma.s.l. (Fig. 8). the stems grow buried in the soil when are in avegetative state or, in some cases, stand out to the middle. it canonly be observed when very showy flowers are produced.

Associated vegetation

on the slopes and pampas, that are completely desertic, onlyHaageocereus decumbens in very few specimens occurs; insome other places towards the pampas Tyllandsia purpurea isfound.

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Fig. 1 - Islaya camanaensis: stem showing ribs and areolas. Fig. 2 - Purple red flowers of Islaya camanaensis in hillside habitat.

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Fig. 3 - Islaya camanaensis: a, habit; B, areole and spines; C, flower; d, vertical section of flower; e, style and stygmata; F, corolla-liketepal; g, calyx-like tepal; H, hypanthium bract; i, fruit; J, seed.

Distribution

recorded only from la Pampa, upper part of the gorge,between 800 and 1050 m a.s.l., Islaya camanaensis is endemicto an area of about 50 km2 in the province of Camaná,department of arequipa (Fig. 10).

Phenology

the species grows throughout the year, camouflaged inthe midst of the extensive pampas and hills within theCamaneño desert, half buried so that only the apical partappears. it is visible only by its lilac or purple flowers,which are very showy (Figs. 2 & 6). the flowering periodextends from september to october, the fruiting fromnovember to december.

Etymology

the epithet “camanaensis” refers to the name of the pro-vince of Camaná, the hilly area in the department ofarequipa where the new species occurs above.

Taxonomic remarks

Islaya camanaensis Cáceres differs from I. islayensis

ritter and I. divaricatiflora (Forster) Backeb. beingobovoid, slightly compressed at the apex, and having oldstems branched, very marked ribs, prominentareolas, ovalwith two sets of almost uniform short spines, outwardly out-stretched, intense purple or light purple flowers when theanthesis is completely open (Fig. 6), filaments of stamensshorter than the style, very yellow anthers and stigma pro-truding above the whitish stamens, small ovoid toobovoides fruits, covered with wool and with reddish bris-tles (Fig. 5b) developed long with remains of perigonium,reniform seeds, smooth blackish and bright 2 mm.

it could also be confused with Eryosice caligophila r.Pinto from Chile, because it has purple red flowers, but this-latter is easily distinguished because it has conical roots (Fig.5a), 13ribs, tubers and mamillas placed under the areolas

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Fig. 4 - Islaya camanaensis in the field. the upper part only isvisible, most of the body being buried.

Fig. 7 - Habit of the new species in the pampa alta of Camaná.

Fig. 6 - Mature plant of Islaya camanaensis in full bloom in itsnatural habitat.

Fig. 5 - details of Islaya camanaensis: a) dichotomously branchedroots, up to 15 cm long; b) fruit with the apical part with wool andreddish bristles.

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Characters Islaya divaricatiflora ritter Islaya islayensis (Forster) Backeb. Islaya camanaensis Cáceres

stemovate to hemispheric, 4 to 7 cmthick, apically flattened, halfburied. Colour gray-green.

globose to elongated, cylindrical, erect orrecumbent, 25-30 (40)×20 cm in diameter.Whole stem off ground. Colour light lead

ovoid to obovate branched, 7-12×6-15 cm,half buried. apex lightly compressed.Colour dark lead.

root Undeveloped, up to 15 cm long,branched and fibrous

superficial, up to 60 cm long. dichotomous, branched, 15-25 cm long

areoleselongate or oval, 3-6×3-5 mm,tomentose, gray

rounded, 10-15×5-10 mm, hard and thick, grayto blackish.

oval 8-10×2-4 mm, with two rows of shortspines. grayish green in colour

ribsribs 16-25, uniform, elliptic, 6-8mm height, crenate often wrin-kled between furrows

16-25. in some specimens 1-1.7 cm between theribs and 1.3 cm prominence. Highly variable

16-18 with protuberances, uniformly positio-ned. Height between ribs 5 mm, parenchymaand marrow of the bark 2 cm reddish.

spines

12-16 brown, radial spines, well-needle-shaped, around the areola,3-7 mm long, tenuous. Centralspines 4-8, stronger, 4-10 mmlong, in all directions.

15-25 inhomogeneous spines, very hard andwooly, 12×8 mm wide, distant within areoles 1-8mm. Bristles10 mm, long blades.

8-10 almost homogeneous spines of 1-2 mmin average in the margin of the areola and 4central spines of 2-3 mm all extendedtowards the sides

Flower coloryellow pale to greenish at thebase and reddish at the top

light yellow to yellow with reddish border dark lilac to light purple.

HypanthiumHirsute floral tube whitishwoolly.à no bristles, nor nectarife-rous chamber.

lanuginous floral tubedense lanuginous floral tube, covering up tohalf of the tepals, 1.2×0.8 cm wide, 0.5-1×1.5 cm in the apical part.

Calyx tepals

tépals 10-13×5-7 mm, funnel-shaped, with small, red-brownsmall scales, with white wool andmany greenish-yellow tepals orsoft yellow to red, bristles 7-12mm, projecting vertically.

wooly, thin yellow to greenish.subulate, dark lilac 3-5×1.5-2.5 mm in seriesof two to three, hardly distinguishable bydense wool.

Corolla tepals

yellow or green at the base andreddish upwards. 10-14×2-4 mm,reduced, rounded or slightly acu-minate, yellowish green, light yel-low to reddish at the top.

yellow apical tufts 2-4 cm, floral tube with tuftsof dense wool and translucent yellow bristles.

numerous obovate acute at the apex, slightlymucronate with a dark central stain along thetepal. 2.8- 3.2×0.6 cm. light to dark lilac.not reddish.

androecium

stamens numerous with thin fila-ment and whitish anthers 1 mm,almost at the level of stigma. thestamens are inserted at the base oftepals

stamens numerous. with thin filaments and whi-tish anthers

stamens numerous with cylindrical, clearfilaments shorter than the stigma intense yel-low anthers 1-1.2 mm ovary ovoid with fewovules.

gynoecium

ovary elongated style short, paleyellow, inserted at the base oftepals stigmas ca. 7-8, lobed, 3mm long, pale yellow.

ovary elongated. style short with numerousstigmas.

ovary rounded or ovoid, ovules ovoid. stylelight cylindrical, 10 -12×2.5 mm. stigmas10-12 whitish, 4-5×1.2 mm.

Fruit

greenish to dark red on top, 1-2×0.6-1 cm thick, barrel shapedglutinous on the inside with hol-low base. Presence of white woolon the top mostly shiny or softbristles.

different in size, clavate, light pink 3-5 cm long.

Fruit ovoid to obovoide, 0.8-1 cm dark lilacwith areoles of 1 mm, wooly. With nume-rous whitish hairs and very dense perennialred bristles

seeds1.2×0.7-0.5 mm, forehead blackand glabrous. Hilum white.oblong.

ovoid, blackish, opaque, compressed, reniformor obovate, reticulate 3.5×2.5 mm. 23-25 perfruit.

Blackish, reniform 2×1.5.mm, shiny blackforehead, dark brown thread. 6 to 10 seedsper fruit

location lomas de Camanalomas de Chala, atico, Caraveli, ocoña,Camana, Mollendo, arequipa, Moquegua, tacna.

High part of the Pampas gorge

altitude 500-600 m a.s.l. 50-250 m a.s.l. 900-1050 m a.s.l.

Habitat Hills and deep ravines desert sandy slopes below the hills Pampas and high slopes above the hills.

distribution Camaná Costa de Mollendo, Camaná, Caravelí. Camaná

table 1 - Comparition of Islaya camanaensis and the related species occurring in the area.

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(Fig. 1) and larger fruits 2-3.5 cm long (Fig. 5b). it occursabove 900 m a.s.l. in the extensive pampas (Fig. 9) of theprovince of Camaná, department of arequipa (Fig.10).

its habitat is quite peculiar because it inhabits sandy soilsand is usually buried in the ground (Fig. 7), where only halfor almost nothing of its stems appear, unlike I. islayensis

that inhabits sandy soils with abundant limestone andquartz, above 250 m a.s.l., and unlike I. divaricatiflora thatoccurs in the ravines, among 500-600 m a.s.l. and it canremain buried in soft soil and vegetate for many years.

the discriminating features of Islaya camanaensis, com-pared to the two congeneric species occurring in the samearea, are better highlighted in the comparative table shownin table 1.

Conservation status

Islaya camanaensis Cáceres has a wide area in the highpampas of the locality of Camaná and some slopes in a stripthat goes from the 900 to 1050 msnm. the population isbeing threatened at present due to the opening of roads andcarvings that connect the hills of the districts of Camaná withthe upper part of the creek of the bull. the number of indivi-duals between 15 to 30 per 100 m2, approximately 7 indivi-duals per 100 m2. near to the zone roads for irrigations havealso been built, putting in risk the rare plant populations. inthe Pampa the whole area is being populated by dwellings.

Final considerations

according to the present study the genus Islaya Backeb.in the southern region of Peru is conformed by four speciesand one subspecies: Islaya islayensis (Forster) Backeb., I.islayensis subsp. grandis (rauh & Backeb.) g. Charles, I.omasensis ostolaza et Mischler, I. divaricatiflora ritter andI. camanaensis Cáceres which is significantly different fromthe other taxa. the epithet of the new species refers to thename of the province of Camaná where it occurs.

the intense rains of 2013 and 2014 in these areas where itnever rains in arequipa allowed its finding.

it is a rare species and almost does not share with asso-ciated flora in its habitat, and only the presence of

Haageocereus decumbens (Vaupel) Backeb. and sometyllandsias found in the ravines has been observed.

the present state of conservation of I. camanaensis isunfavorable, since its little population is confined in arestricted zone where some human has recently been startd.it has been possible to evaluate up to 7 individuals per 100m2 in an area 50 km2. Besides, a high number of adult plantshave been found dead (3 out of 10 individuals). in addition,carvings that cross the pampas to the province of Camanáhave been recently opened. in conclusion the new speciesshould be considered in critical danger.

Fig. 10 - distribution of Islaya camanaensis in the province ofCamaná, department of arequipa (Peru).

Fig. 9 - natural landscape of the locus classicus of Islaya camanaensis.Fig. 8 - Habitat of Islaya camanaensis in the pampa alta of Camaná.

aCKnoWledgMents

a special thanks to the colleagues of the section of Botanyfrom the Biology school of the University agustín nationalPark, for your collaboration and support; to leoncio MariñoHerrera, director of the Herbarium arequipense HUsa, forallowing to review material present in this Herbarium.thanks also to CienCia aCtiVa ConCyteC-Unsa, forthe financing granted graduated from the training internshipat the University of Palermo (italy).

resUMen – Estudios taxonómicos sobre el género islaya(Cactaceae): islaya camanaensis, nueva especie endémica

de la región de Arequipa (Perú) – Como parte de un pro-yecto de investigación sobre cactaceae en la región sur delPerú, una población del género Islaya fue particularmentecrítica. el afectuoso estudio taxonómico ha permitido des-cribirla como una nueva especie con el nombre de Islaya

camanaensis, en referencia a la provincia de Camaná, dondesu población utiliza la altitud de 900-1050 m s.n.m. elnuevo taxón muestra claras diferencias con respecto a otrasespecies del mismo género presentes en el Perú. en particu-lar, se refieren a la raíz y a la forma del tallo, por lo tanto lascostillas, las areolas, el color de las flores y, finalmente,también el fruto y las semillas. Islaya camanaensis, en sudifícil hábitat de pampas áridas, en el departamento dearequipa, florece en septiembre y da fruto en noviembre-diciembre. de las encuestas realizadas, la nueva especie esbastante rara: en un crucero de 50 km, se producen en pro-medio 7 individuos por cada 100 m2. las principalesamenazas a las que está expuesta son la construcción decarreteras y concesiones de tierras para ser utilizadaspara la expansión de la agricultura y la construcción deedificios.

riassUnto – Studi tassonomici sul genere islaya(Cactaceae): islaya camanaensis, nuova specie endemica

della regione di Arequipa (Perù) – nell’ambito di un pro-getto di ricerca sulle cactacee della regione meridionaledel Perù, una popolazione del genere Islaya è risultata par-ticolarmente critica. lo studio tassonomico affettuato hapermesso di poterla descrivere come nuova specie con ilnome Islaya camanaensis, in riferimento alla provincia diCamaná dove la sua popolazione ricorre alla quota di 900-1050 m s.l.m. il nuovo taxon mostra chiare differenzerispetto alle altre specie congeneri presenti in Perù. esseriguardano la radice e la forma del fusto, quindi le costolature,le areole, il colore dei fiori e, infine, anche il frutto e i semi.Islaya camanaensis, nel difficile habitat della pampas arida,fiorisce in settembre e fruttifica in novembre-dicembre. dairilevi effettuati la nuova specie risulta abbastanza rara: in untransetto di 50 km, mediamente ricorrono 7 individui su100 m2. le principali minacce a cui essa è esposta sono lacostruzione di strade e le concessioni di terreni da destina-re all’espansione dell’agricoltura e alla costruzione di edifici.

reFerenCes

anderson e.F., 2001. – The Cactus Family. – timber Press.oregon Usa.

BaCKeBerg C., 1958-1962. – Die Cactaceae: Handbuch der

Kakteenkunde. – Jena.KatterMann F., 1994. – Eriosyce. – succulent Plant research

1. richmond.nyFFeler r. & eggli U., 1997. – Comparative stem anatomy

and eriosyce sensu lato (Cactaceae). – annals of Botany80: 767-786.

ostolaza C., 2014. – Todos los Cactus del Perú. – MinaM,Peru.

ritter F., 1964. – Kakteen in Sudamerica. – ergerbise Meiner.20 jahrigen Feldforschungen, 4. Peru. germany.

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