Class Mammalia Subclass Prototheria

‡ Order TriconodontaMorganucodontidaeAmphilestidae

Triconodontidae ‡ Order Docodonta Order Monotremata

‡ Subclass Allotheria Order Haramiyoidea

Order Multituberculata Subclass Theria

‡ Infraclass Trituberculata Order Symmetrodonta

Kuehnoetheriidae Order Eupantotheria

Dryolestidae Infraclass Metatheria Infraclass Eutheria

(After Carroll 1988)

‡“Class” Mammaliformes Order Morganucodontia

Morganucodontidae Order Docodonta Order Haramiyoidea

Class Mammalia Subclass Prototheria

Order Platypoda Order Tachyglossa

Subclass Theriiformes ‡ Infraclass Allotheria

Order Multituberculata ‡ Infraclass Triconodontia Infraclass Holotheria ‡ Order Symmetrodontia

‡ Order Eupantotheria Order Metatheria Order Eutheria

(After McKenna & Bell 1997)

PROTOTHERIA – Order TriconodontaMorganucodon (late Triassic)

PROTOTHERIA – Order TriconodontaMorganucodon (late Triassic)

PROTOTHERIA – Order TriconodontaTriconodon

Jurassic - Cretaceous

PROTOTHERIA – Order Docodontia

Haldanodon (mid-late Jurassic)

ALLOTHERIA – Order Multituberculata

Late Triassic-Oligocene (160 million yrs.)

ALLOTHERIA – Order HaramiyoideaLate Triassic – Jurassic, Europe, Greenland & Africa

ALLOTHERIA – Order MultituberculataFamily: Eucosmodontidae

Kryptobaatar late Cretaceous, Mongolia

ALLOTHERIA – Order Multituberculata

Ptilodus Paleocene N. America

Ornithorhynchus anatinus

PROTOTHERIA -- Order MonotremataFamily Ornithorhynchidae

ObdurodonMiocene, Australia

OrnithorhynchusRecent

Deciduous teeth

SteropodonCretaceous, Australia

KollikodonCretaceous, Australia

MonotrematumPaleocene, South America

PROTOTHERIA -- Order MonotremataFamily Ornithorhynchidae (fossil history)

TachyglossusShort-beaked echidna (Australia, Tasmania, New Guinea)

PROTOTHERIA -- Order MonotremataFamily Tachyglossidae (echidnas)

PROTOTHERIA -- Order MonotremataFamily Tachyglossidae (echidnas)

ZaglossusLong-beaked echidna (New Guinea)

ORDER SYMMETRODOTA earliest therians

Vincelestes early Cretaceus, Argentina

PROTOTHERIAN - THERIAN CONTRASTS

PROTOTHERIANS THERIANS (monotremes) (marsupials & placentals)

Teeth Deciduous teeth only Permanent dentition multi-cusped molars tribosphenic molars

Skeleton Therapsid features: skull with “extra” bones fusion of skull bones cervical ribs cervical ribs lost “reptilian” shoulder girdle “mammalian” shoulder sprawling limb posture upright limb posture Reproduction “reptilian” cloacal opening separate urogenital & anal openings oviparous viviparous mammary glands not well-developed teats forming teats

POSSIBLE SUB-ORDER RELATIONSHIPS

MAMMALPOLYPHYLY

MONOTREMES PLUSMULTITUBERCULATES

MONOTREMES PLUSMARSUPIALS

PROTOTHERIA PLUSTHERIA(prevailing view)