Placoparina dravidicus Whittard 1940

Placoparina ? dravidicus (Reed, 1915) Fig. 13.2 1915 Cheirurus dravidicus; Reed, p. 48, pl. 8, fig. 12. Material. Holotype: pygidium from Lower Naungkangyi Beds (probable Darriwilian) at Man-shio, Fig. 13.2 (Reed, 1915, pl. 8, fig. 12), GSI 11559. Discussion. The species was described by Reed (1915) on the basis of one pygidium; a cast from the counterpart of the type specimen is illustrated here. Reed’s illustrations show the tips of the three pairs of pygidial spines. The anterior pair is not noticeably more strongly developed than the other two pairs, as it is in cheirurines, and the posterior pair is also prominent in P.? dravidicus. Lane (1971) showed that pygidia were the most informative sclerite in cheirurids, and it seems improbable that P. ? dravidicus is a cheirurine given its pygidial structure. Eccoptochile has a pygidium with three pairs of obtuse spines (type material of the type species in Horný & Bastl, 1970, pl. 14, fig. 1). The pygidium of Placoparina Whittard, 1940, is generally similar. However, the relatively obtuse lobes, and their marked fulcrum are more like those on Placoparina (Whittard, 1958) than Eccoptochile, and dravidicus is tentatively assigned herein to Placoparina. The identity of Reed’s species cannot confidently be resolved without further collections.
Published as part of Fortey, Richard A., Wernette, Shelly J. & Hughes, Nigel C., 2022, Revision of F. R. C. Reed's Ordovician trilobite types from Myanmar (Burma) and western Yunnan Province, China, pp. 301-356 in Zootaxa 5162 (4) on page 340, DOI: 10.11646/zootaxa.5162.4.1, http://zenodo.org/record/6810290
{"references":["Reed, F. R. C. (1915) Supplementary Memoir on new Ordovician and Silurian fossils from the Northern Shan States. Palaeontologia Indica, New Series 6, 1 - 98.","Lane, P. D. (1971) British Cheiruridae (Trilobita). Monographs of the Palaeontographical Society, 530, 1 - 95.","Horny, R. & Bastl, F. (1970) Type specimen of fossils in the National Museum, Prague. Trilobita. National Museum, Prague, Prague, 354 pp.","Whittard, W. F. (1940) The Ordovician trilobite faunas of the Shelve-Corndon District, West Shropshire, Part 1. Annals and Magazine of Natural History, Series 11, 5, 153 - 172.","Whittard, W. F. (1958) The Ordovician trilobites of the Shelve inlier, west Shropshire. Monographs of the Palaeontographical Society, 1958, 71 - 116."]}