Revision of F. R. C. Reed’s Ordovician trilobite types from Myanmar (Burma) and western Yunnan Province, China
Author
Fortey, Richard A.
Department of Earth Sciences, Museum of Natural History, Cromwell Road, London, SW 7 5 BD, UK.
Author
Wernette, Shelly J.
Department of Earth and Planetary Sciences, University of California, Riverside, CA 92521, USA. & Department of Geography and Environmental Studies, Texas State University, San Marcos, TX 78666, USA
Author
Hughes, Nigel C.
text
Zootaxa
2022
2022-07-08
5162
4
301
356
journal article
93239
10.11646/zootaxa.5162.4.1
7d343017-483e-43be-9439-d06e748fc54e
1175-5326
6810290
DD2279FA-E8F1-4951-A5CA-91082E875580
Hadromeros
?
submitis
(
Reed, 1915
)
Fig. 13.1
1915
Cheirurus submitis
Reed
, p. 49, pl. 8, figs 13,14.
Material
.
Lectotype
(selected herein): cranidium from
Upper Naungkangyi Beds
(Katian),
Lilu
, northern
Shan State
,
Myanmar
,
Fig. 13.1
(
Reed, 1915
, pl. 8, figs 13,14),
GSI
11560.
Discussion.
We illustrate here a cast taken from the
lectotype
, original of
Reed (1915
, pl 8. fig. 14). Only the cephalon is known of this species, which is only generally cheirurine, and invites comparison with those of many other species of similar age. It does, however, have very large, prominent but scattered tubercles on the cheeks and frontal lobe of the glabella. Many somewhat similar later Ordovician Chinese cheirurines have been assigned to the genus
Parisoceraurus
by
Zhou & Zhen (2008)
but these do not have such prominent tubercles. One species from the Pagoda Formation of Sichuan attributed (under open nomenclature) to
Hadromeros
by
Zhou
et al.
(2016
, pl. 14, fig. 14) does invite comparison with
H
.?
submitis
in showing very coarse, scattered tubercles over the fixed cheeks and forward part of the glabella, and may support a tentative assignment to
Hadromeros
. However, the Sichuan specimen and the type species of
Hadromeros
both show relatively long (tr.) glabellar furrows compared with H.?
submitis
, while the frontal glabellar lobe of the latter is relatively short (sag.) and wide. This structure seems to be unusual in cheirurids, and the distinctive glabellar lobation of the
Myanmar
species may indicate that it could belong to an undescribed genus, but without a pygidium this cannot be verified.