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Journal of Paleontology 91(1):100–115
than second and third; precervical grooves inclined poster- olaterally and do not cross midline; cervical groove concave forward; two or three thoracic segments exposed dorsally; pleonal pleurae strongly reduced or absent; telson and uropods lack any indication of having been setose.
Etymology.—The generic name refers to Yunnan, the province from which the specimens were collected, and the Latin copia = abundance, in reference to the abundance of specimens referable to the genus. The gender is feminine.
Remarks.—The specimens collected from the Luoping Biota represent taxa that can confidently be assigned to a new genus. Previously, Taylor et al. (2001) described Schimperella acanthocercus from Triassic rocks in Guizhou, China. Species of Schimperella differ in several ways from the Luoping material sufficiently to warrant description of a new genus. Schimperella Bill, 1914, was based upon two species from the Triassic of France: S. beneckei, the type species by subsequent designation of Hessler (1969), and S. kessleri. The unique nature of S. kessleri has been questioned (Taylor et al., 2001). Certainly the illustrations of the species (Bill, 1914, pl. 16, figs. 3, 4) suggest that it may be the female counterpart of S.
beneckei.In addition, Schimperella spp. have been reported from the Middle Triassic Meride Limestone in northeastern Italy (Largi and Tintori, 2007) and from the Middle Triassic (middle Anisian) Strelovec Formation in Slovenia (Križna and Hitij, 2010). This latter occurrence might be shown to be more or less contemporaneous with the Luoping occurrences; however, that has yet to be tested. Schimperella kessleri exhibits a well-developed marsu-
pium, whereas the type species appears to be a male. Regardless, species of Schimperella are characterized by an extremely large, obovate antennal scale; slender basal antennular segments; a weak, transverse precervical groove; transverse cervical groove; carapace covering nearly all thoracic segments dorsally; pleonal pleura that are moderately well developed; and setose telson and
uropods.By contrast, the antennal scale of Yunnanocopia spp. is ovate with an acute tip, the antennular segments are stout, the precervical grooves are inclined posterolaterally, the cervical groove is concave forward, two or three thoracic segments are exposed dorsally, pleonal pleurae are strongly reduced or absent, and the telson and uropods lack any indication of having been setose. Thus, assignment of the lophogastrids from the Luoping Biota to a new genus seems fully warranted.
Yunnanocopia grandis new species Figures 2.1–2.7, 3.1–3.6, 4.1–4.6
Diagnosis.—Third element of antennular base shorter than second; antennal scale weakly convex laterally, ovoid, longer than wide; endophragmal skeleton narrows posteriorly; at least six pairs of oostegites form prominent marsupium; pleonal tergites irregularly nodose; pleura not evident; telson spatulate; uropods long, flabellate.
Description.—Large, stout eucopiids. Antennules biflagellate; antennular base with first element longer than wide, rectangular, outer and inner margins weakly convex; second segment short,
about as wide as long, rectangular; third segment shorter, wider than long, narrowing axially, extends nearly to tip of antennal scale. Antennular flagellae of equal diameter, but two different lengths; inner one is much shorter, directed straight forward. Antenna longer than the antennules. First antennal segment longer than wide, rectangular; second segment apparently rectangular, about as wide as first segment but shorter; flagellum more stout than antennular ones. Antennal scale weakly convex laterally, ovoid, longer than wide; thickened rim on outer margin. Basal element of antennal scale equidimensional, outer margin weakly convex, inner margin apparently broken, distal margin sinuous, with a small spine on outer corner. Cephalothorax longer than wide, anterior margin obscured;
weakly convex laterally; deeply concave posteriorly, rimmed, posterolateral corner projected as rounded, posterolaterally directed flange; rostrum inferred to be short, triangular. Cervical groove rims anterolateral margin and curves from anterolateral margin posteriorly at 45° angle, then extends straight to axis at much lower angle to midline; as it approaches midline, it curves and parallels midline for short distance before crossing midline. Precervical groove intersects cervical groove laterally, then arcs concave forward and traverses obliquely about one-quarter the distance toward axis, defining hepatic region; expressed as grooves on the holotype. Cephalic region short. No evidence of lateral rim or any ornamentation posterior to cervical groove. Two or possibly three thoracomeres not covered by carapace dorsally (40749). Underside of anterior part of cephalothorax rimmed.
Endophragmal skeleton well calcified, six apodemes
visible, straight, inclined posterolaterally from midline; seven pairs of coxal holes evident, all posterior to cervical groove; endophragmal skeleton narrows posteriorly, widest at position of third and fourth coxal holes. Marsupium well developed on female specimens. Right
oostegites ovate, posterior margin concave forward, with thickened rim, posterior-most oöstegite apparently arising on last thoracomere, extending from position of basal elements of thoracopods over half the distance across preserved portion of animal; six are preserved. Left oostegites with convex-forward, thickened anterior margin. Left oostegites overlap the right ones. Six pleonites, first five about equal length, width decreases
slightly posteriorly; sixth pleonite longer than the fifth; tergites irregularly nodose, rimmed along posterior margin of each pleonite, lateral margins rounded, bordered by thickened rim. In ventral aspect pleonites are strongly calcified anteriorly and axially, flaring anteriorly into sharp processes. Pleopods visible on pleonites 3–6, flagellate, multiarticulate, nearly as long as somite width; basal element ovate, slightly longer than wide. Telson spatulate, tapers slightly posteriorly, anteriorly not
quite as wide as sixth pleonal somite, axially sulcate from anterior end nearly to termination dorsally and with broad granular ridge arising proximally, bifurcating distally, on ventral side; weakly rimmed marginally; distally smoothly rounded, lateral margins of telson appear granular. Uropods long, flabellate, exopod markedly longer than endopod, diaeresis of exopod lies posterior to end of telson, two
nodes at about midwidth of diaeresis (40749). Endopod flabellate, extending to tip of telson.
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