麂属(Muntiacus)的分类及其系统发育研究

麂属(Muntiacus)是一群中小型草食有蹄类,为东洋界的特有属,是典型的热带、亚热带类群。在我国,麂属的分布仅限于长江流域及其以南各地,为我国南方的重要毛皮兽。 以往对麂属的研究多限于一般的形态分类,对其系统发育尚未深入研究。在种级分类上至今还存在一些混乱现象。本文试图用分支系统学(Cladistics)的方法,对麂属的种级分化进行系统整理,并对其系统发育作一初步探讨。

TAXONOMIC AND PHYLOGENETIC STUDIES ON THE GENUS MUNTIACUS

Muntiacus(Artiodactyla:Cervidae) is only found in tropical and subtropical areas of south Asia.We examined nearly 200 skulls and skins, read a part of the articles on the fossil of this genus, to inquire into its origin, differentiation and phylogeny.10 effective species comprise the genus, 5 of which are fossil species.Fossil species: M.nanus Teilhard(late Pliocene and early Pleistocene, in southeast Shanxiand Yuenmou, Yunnan, China).M.cf.nanus Teilhard et TrassaertGate Miocene, in Lufeng, Yunnan). M.fenghoensis Chow(late Pliocene to early Pleistocene, in Jaocheng, Shanxi China). M.lacustris Teilhard et Trassaertdate Pliocene to early Pleistocene, in so-theast Shanxi and Yuanmou, Yunnan China). M.bohlini Teilhard (early Pleistocene, at Niheuan Xianhua, Hebei andZhoukoudien near Beijing, China).Existing species:M.reevesi Ogilby(Chinese muntjac). M .rooseveltorum Osgood(Roosevelt's muntiac). M.crinifrons Sclater (Black muntjac). M.feae> Thomas et Doria(Fea's muntjac). M.muntjak Zimmermann(Indian muntjac).By comparison and analysis, we come to the conclusion:1. M.rooseveltorum is not a hybrid of M.muntjak and M.reevesi. 4 pieces of skin of M.rooseveltorum purchased in west Yunnan(place of production is indefinite)are deposited in Kunming Institute of Zoology.It is a new record in China.M.lachrymans teesdalei described by Lydekker(1915) as having relatively small preorbital pit and premaxillae separated from nasals, should be M.rooseveltorum.Groves(1982)describes a new species, Muntiacus atherodes, should be M.muntjak, his holotype(BM71.3088)in fact, is a subadult male without formed antler branches.2. The developmental trend of Muntiacus is from the grassland of low hill, gully and shrub to deciduous forest of moderate and high mountains. Morphologically, the antler pedicels become longer, ears bigger, limbs longer, lateral toes degenerated, frontal glands developed.3. Male Muntiacus has a pair of short antlers which are divided into two branches.The antler pedicels are long.The frontal sides are provided with ridges extending from pedicel to P~3.In living species the frontal and chin glands are found.An evolutionary tree is established(fig. 5).4. From the geological age of the fossil and the distribution of living species, we presume that Muntiacus evolved in midor late-Pliocene. The origin place may be north and southwest of China.5. The earliest fossil record of M.reevesi shows that it evolved in early and mid-Pleistocene, of M.muntjak mid-and late-Pleistocene.M.muntjak is still living in islands of Ceylon, Java, Sumatra, Borneo and Hainan etc. That means that the existing muntjac originated in early or mid-Pleistocene, as these islands were separated from the main continent.6. Of the existing five species, M.reevesi and M.feae are smaller or medium in size, antler pedicals shorter, limbs shorter, lateral toes developed, chromosome diploids more, with more primitive ancestral characteristics.Their fossils told us that they lived in early and mid-Pleistocene.We infer that the two species had formed two branches before mid-Pleistocene.