Revision on the Type Species of the Genus Kunmingaspis Chang, 1964 (Trilobita)

Based on the new material collected from the Douposi Formation at Shangwuying Village, Yiliang County Yunnan Province, the type species of the genus Kunmingaspis Chang, 1964 is revised. We deny the opinion to identify differentiation between two genera (Kunmingaspis and Yuehsienhszella), Zhang (1964) and Jell and Hughes (1997) considered that “the eye ridge meeting the axial furrow at the level of the rear of the anterior glabellar lobe is distinctive of the genus”. Because an indistinct connection between frontal lobe of glabella and ocular ridge is difficult to be identified on some specimens. The real differentiations selected to be valid are the outline and feature of the frontal lobe of the glabella. Similarly, such as tip of organs about characters (also called character of degradation, or obscure character) can not be excessively weighted in stage of early classification or identification when the phylogeny is unclear，for instance, the S4, the posterior end of several axial ring (may be including the terminal axial piece) of pygidium etc. and invariability and stability of characters should be listed in the diagnosis to distinguish it from other genera. Kunmingaspis differs from Yuehsienszella mainly in having wider less tapering forward glabella with broadly rounded anterior margin, narrower fixigenae between palpebral lobes, relatively longer palpebral lobe of about 1/3 glabellar length (sag.), by contrast in Yuehsienhszella the palpebral lobe is about 1/4 glabellar length (sag.). Besides Yuehsienhszella has a shallower anterior border furrow, wider fixigenae between palpebral lobes (tr.), shallower less curving forward posterior border furrow medially and broader less tapering backward pygidial axis. In the present paper Kunmingaspis yunnanensis Chang, 1964, K. qianbeiensis Zhou in Lu et al., 1974, K. songlinensis Lee in Yin et Lee, 1978, K. longa Zhou in Zhang et al., 1980, K. brevica Zhou in Zhang et al., 1980 are considered as synonymous with K. sakesarensisa (King, 1941). Biostratigraphical, it can be correlated closely between the Yangtze Platform and Himalaya Area (Pakistan or Indian subcontinent).

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