A possible mammal, Gondwanadon tapani, has been described from near the village of Tiki, Madhya Pradesh (figure 2.5, table 2.3). Gondwanadon is based on an incomplete, two-rooted, molariform tooth, said to be similar to figure 2.5. Mesozoic mammals of India. Asterisks, Late Triassic-Early Jurassic (localities 1-4); diamond, Cretaceous (localities 5, 6). Localities or local faunas: 1, Tiki (Tiki Formation; Carnian, Madhya Pradesh); 2, Paikasigudem; 3, Manganpalli; 4, Yamanapalli (Kota Formation; ?Early Jurassic, Andhra Pradesh); 5, Naskal; 6, Rangapur (Intertrappean Beds; Maastrichtian, Andhra Pradesh).
figure 2.5. Mesozoic mammals of India. Asterisks, Late Triassic-Early Jurassic (localities 1-4); diamond, Cretaceous (localities 5, 6). Localities or local faunas: 1, Tiki (Tiki Formation; Carnian, Madhya Pradesh); 2, Paikasigudem; 3, Manganpalli; 4, Yamanapalli (Kota Formation; ?Early Jurassic, Andhra Pradesh); 5, Naskal; 6, Rangapur (Intertrappean Beds; Maastrichtian, Andhra Pradesh).
those of Morganucodon except in relative cusp development (Datta and Das, 1996). The occurrence is in the lower part of the Tiki Formation, Gondwana Supergroup, and is believed to be Carnian in age, based on a comparison of the flora and fauna (Maleri fauna, see Jain and Roy-Chowdhury, 1987) to the Keuper. Correlations suggest that this occurrence may be slightly older than that of Ade-lobasileus from the Dockum of Texas (Lucas and Luo, 1993). If the correlations and taxonomic identity are upheld, Gondwanadon may prove to be the oldest identified mammal (Datta and Das, 1996).2
2 Footprints named Cynodontipus, from the Early to Middle
Triassic of France, show traces of hair. They have been alternately attributed to a cynodont (Ellenberger, 1976) or a mammal (Sarjeant, 2000). Given the equivocal nature of the evidence, the affinities of this ichnotaxon remain unresolved.
The Kota Formation, India, has yielded an important assemblage of fossil vertebrates, including several early mammals. The unit may have a wide stratigraphic range. The age of the vertebrate fauna is not well understood; fishes and palynomorphs suggest Early Jurassic, whereas ostracods are more similar to those of the Middle Jurassic (see references in Prasad and Manhas, 1997). We follow the prevailing view (e.g., Jain and Roy-Chowdhury, 1987) and tentatively accept an Early Jurassic (Liassic) age for the mammals of the Kota Formation.3
3 However, a recent abstract (Prasad and Manhas, 1999) suggests that the mammal-bearing part of the unit may actually be as young as Early Cretaceous (Barremian-Aptian). Clearly, interpretation of the biogeographic and biostratigraphic significance of the Kota mammals must be approached with extreme caution and should not be based solely on comparison of isolated mammalian teeth.
table 2.3. Late Triassic-Early Jurassic Mammals of India (see figure 2.5; locality numbers do not correspond). Localities: 1, Tiki (Tiki Formation; Carnian, Late Triassic); 2, Manganpalli; 3, Paikasigudem; 4, Yamanapalli (all Kota Formation, ?Early Jurassic)
Mammalia incertae sedis (3) Morganucodonta
Indozostrodon simpsoni (4) ?Morganucodontidae
Gondwanadon tapani (1) Indotherium pranhitai (3) Eutriconodonta
Family incertae sedis
Dyskritodon indicus (3) ?"Amphilestidae"
Paikasigudodon yadagirii (3) Gen. et sp. indet. (3) Archaic "symmetrodontans" Family incertae sedis
Trishulotherium kotaensis (3) ?Amphidontidae
Nakunodon paikasiensis (3) ?Kuehneotheriidae
Kotatherium haldanei (2)
The Kota Formation includes limestones and sandstones, with intercalated claystone horizons, but mammals and most of the other terrestrial vertebrates have been collected from the claystones (Prasad and Manhas, 1997). A review of the vertebrate assemblage is given by Jain (1980).
Mammalian remains from the Kota are reported to include postcranial and skull elements (Datta et al., 1978), but thus far only isolated teeth have been described. Three localities have yielded mammals, all in the Pranhita-Godavari Valley, Adilabad District, Andhra Pradesh (figure 2.5). The first is near the village of Manganpalli, which has yielded upper molars of Kotatherium haldanei (see Datta, 1981). These appear to belong to some sort of primitive "symmetrodontan" and are distinct from the kuehneo-theriids of the European Late Triassic-Early Jurassic. Whether or not K. haldanei is related to Tinodontidae (Datta, 1981; Prasad and Manhas, 1997, see chapter 9), otherwise known from the Late Jurassic-Early Cretaceous, is uncertain. A second, nearby site in the vicinity of Yamanapalli has yielded a single tooth referred to the megazostrodontid morganucodontan, Indozostrodon simpsoni. The remaining mammals of the Kota Formation are from a locality near the village of Paikasigudem. Most striking of these is the eutriconodont Dyskritodon indicus, known by two incomplete lower molars. The species shares an unusual cusp pattern (in which cusp b is strongly reduced) with D. amaghizi from the Berriasian of Morocco (Prasad and Manhas, 2002). Paikasigudodon yada-girii, based on an upper molar with a slightly triangulated cusp pattern, may represent an "amphilestid" eutricon-odontan (chapter 7). Indotherium pranhitai, known by upper molar fragments, was initially considered to be a "symmetrodontan" (Yadagiri, 1984). Restudy by Prasad and Manhas (1997, 2002) showed that it compares more favorably with morganucodontid "triconodonts," such as Morganucodon watsoni and Eozostrodon parvus.
Trishulotherium kotaensis is known by a single, worn lower molar (Yadagiri, 1984). It has a "symmetrodontan" cusp arrangement and differs from Kuehneotherium in a number of ways, but little more than this can be said of the species at present (Prasad and Manhas, 1997). The final described mammal of the Kota Formation is Nakunodon paikasiensis, which is known from an upper molar that is almost monocuspid. This pattern is analogous to that of the Late Jurassic North Am erican "symmetrodontan" Am-phidon, and on this basis Nakunodon has been tentatively referred to the Amphidontidae (Yadagiri, 1985; Prasad and Manhas, 1997). Prasad and Manhas (1999) reported another mammal from the Paikasigudem locality. It is vaguely similar to docodontans on the one hand, to the "pseudotribosphenic" Shuotherium (chapter 6) on the other, and possibly represents a hitherto unknown mammalian lineage.
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