Asia

Several sites in Asia (figure 2.4, table 2.6) have yielded single specimens of mammals that may be Jurassic, perhaps Middle Jurassic, in age. One of these is Luchang (Luzhang), in Sichuan Province, China, where a fragmentary tooth with two roots has been reported (Chow and Rich, 1984b). The occurrence is in the lower Yimen Formation and is of Early Jurassic age. A second occurrence is that of Manchurodon simplicidens, from the Zha-zy-ao Mine, Liaoning Province. The species is based on a well-preserved dentary and a scapula that may be associated (Yabe and Shikama, 1938); unfortunately, the specimen appears to be lost. There is also confusion as to the age of this occurrence. Yabe and Shikama (1938) described the fossil as having come from the Husin Series, which they believed to be Jurassic in age on the basis of plant fossils. As discussed later, the Husin (Fuxin) is generally regarded as Lower Cretaceous and, indeed, a number of noteworthy mammals of this age occur in western Liaoning (Wang et al., 1995, Wang, Hu, Li, et al., 2001). However, the occurrence of Manchurodon is now generally believed to be in the Wa-fang-dian Formation, which is reported to be Jurassic, perhaps Middle or Upper Jurassic (Zhang, 1984; Zhou et al., 1991). In light of the new dates for the Lower Cretaceous of Liaoning (Swisher et al., 1999) and the possibility that the age for much of table 2.6. Middle Jurassic (?) Mammals of Asia and European part of Russia (see figures 2.3, 2.11; locality numbers do not correspond between table and figures). Localities or local faunas: 1, Luzhang, China (lower Yimen Formation, Early Jurassic); 2, Zha-zy-ao Mine, China (Wa-fang-dian Formation, ?Middle or Late Jurassic); 3, Fangshen, China (Haifanggou Formation, ?Middle Jurassic); 4, Kalmakerchin; 5, Tashkumyr (both in the Balabansay Formation; Callovian, Kirghizia); 6, Peski Quarry, Russia (fissure fillings, Bathonian, Middle Jurassic)

:Mammalia incertae sedis Family incertae sedis Gen. et sp. indet. (1) ?Morganucodonta

?Morganucodontidae Gen. et sp. indet. (6) ?Docodonta

Family incertae sedis Gen. et sp. indet. (4) Docodonta Docodontidae

Gen. et sp. indet. (5) Archaic "symmetrodontans" ?Amphidontidae

Manchurodon simplicidens (2) Eutriconodonta "Amphilestidae"

Liaotherium gracile (3)

Mesozoic sequence may be revised upward, this estimate may be too old.

Liaotherium gracile represents another Jurassic, perhaps Middle Jurassic, mammal from China. From the Fangshen locality, Haifanggou Formation (= Jiulongshan Formation), Lingyuan County, Liaoning Province, the specimen consists of a dentary with part of the last molar; Liaotherium is tentatively referred to the eutriconodon-tan family "Amphilestidae" (see Zhou et al., 1991, and chapter 7).

The final mammal occurrences in the Middle Jurassic of Asia are from the Balabansay Formation, Fergana Depression, Kirghizia. The site of Kalmakerchin has yielded a possible docodontan, based on a badly broken upper molar and an ulna (Nessov, Kielan-Jaworowska, et al., 1994). Also known from the site are salamanders of the family Karauiidae, known only from the Jurassic; an overlying unit has yielded leaves reported to be of Middle Jurassic age (Averianov, 2000). A second, nearby site, Tashkumyr, has yielded a lower molar referred to Docodonta, as a possible relative of Tegotherium Tatari-nov, 1994, from the Late Jurassic of Mongolia (see chapter 5 and Martin and Averianov, 2001).

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