A New Spelaeogriphacean (Crustacea: Peracarida) from the Upper Jurassic of China

A New Spelaeogriphacean (Crustacea: Peracarida) from the Upper Jurassic of China

Contributions to Zoology, 68 (1) 19-35 (1998) SPB Academic Publishing bv, Amsterdam A new spelaeogriphacean (Crustacea: Peracarida) from the Upper Jurassic of China Shen Yan-bin Rod+S. ² & Frederick+R. Schram² ¹, Taylor 1Nanjing Institute of Geology and Palaeontology, Academia Sinica, 39 East Beijing Road, Nanjing, The 2 People’s Republic of China, 210008; Institute for Systematics and Population Biology, University oj Amsterdam, P.O. Box 94766, 1090 GT Amsterdam, The Netherlands Keywords: Crustacea, Peracarida, Spelaeogriphacea, fossils, Upper Jurrasic north-east China, cladistic analysis Abstract phylogenetic significance for Spelaeogriphus lepidops by Grindley and Hessler (1971). A of is described new monotypic genus Spelaeogriphacea from While work on S. lepidops has been sparse, the Upper Jurassic ofLiaoning Province, north-east China. This continuing research on other fronts has increased new genus and species brings the number of known spelaeo- the number of species credited to this order to three. griphacean taxa to four, the others being two recent forms from second Pires described a recent form, Brazil and (1987) South Africa, and one from the Carboniferous of Potiicoara found in a lake inside the eastern Canada. brasiliensis, The new Chinese form is morphologically(and similar the calcareous cave Gruta do Azul in the Bodo- phylogenetically) very to recent spelaeogriphaceans, Laga that the seenin the recent do suggesting body plan Spelaeogriphacea quena Mountains, MatoGrosso Sul, Brazil. This was achieved in the of the A relatively early history group. form is distinguished from S. lepidops by its shorter cladistic analysis of this and several other peracaridan orders biramous fifth carapace, pleopod, three-segmented indicates that the be Spelaeogriphaceamay a paraphyletic group. mandibular endite and This palp, spinose maxillipedal suggests that much work remains to be done with respect collection to the and the its specific locality, taxonomy phylogenetic relationships among highly considerably that S. peracaridan taxa. distant from of lepidops. Pires also included a phylogenetic analysis of the peracaridan orders, considering the phylogeny of the order as a whole. Introduction Of particular note, she proposed as a result of this analysis a sister-group relationship between the As a result of several specimens obtained by the Spelaeogriphacea and Mictacea. South African Spelaeological Association from un- The third spelaeogriphacean taxon, Acadiocaris derground cave pools in Bat Cave, Table Moun- novascotica, is a Lower Carboniferous form col- tain, South Africa, Gordon (1957, 1960) described lected from the Maritime Provinces of Canadaand a new malacostracan crustacean species, Spelaeo- was described initially by Copeland (1957). It was griphus This later redescribed Schram who lepidops. crustacean possesses a typi- by (1974), placed it cally peracaridan brood pouch with five pairs of into his newly-erected spelaeogriphacean family oostegites, and was thus placed within the Super- Acadiocarididae, reassigning it from the peracaridan ouler Peracarida. While its closest affinities seem Order Anthracocaridacea as previously proposed to be to the Tanaidacea, it is not sufficiently simi- by Brooks (1962). This species is described from lar to any of the existing peracaridan orders for it poorly preserved material, composed of black to be placed comfortably within any of these or- carbonaceous pyritized films on black shale which, ders. Thus, the Order Spelaeogriphacea was erected as Schram (1974) has observed, appears to be in by Gordon (1957) accommodate this and of to new .the process disintegrating as the pyrite in them complicated” taxon. Little research has followed oxidizes. This form several appears to posses ‘primi- up on this initial with the tive’ characters when the other description, exception compared to spe- of work on the and respiratory mechanism its laeogriphacean taxa, such as an absence of an optic Downloaded from Brill.com10/11/2021 09:56:06AM via free access 20 Shen Yan-bin, R.S. Taylor & F.R. Schram - Fossil speleaogriphacean (Crustacea) from China notch in the rectangular carapace, well-developed taxa has also developed on other fronts recently. and elongate thoracopodal endopods, and five pairs Eva E. Pinardo-Moya at the Unidad de Paleontolo- ofwell-developed but relatively small and simple gia, Universidad Autonoma de Madrid is currently the pleopods. working on description of a new spelaeogri- A fourth species of spelaeogriphacean has now phacean taxon from Lower Cretaceous (Barremian) been discovered from two equivalent localities deposits of Las Hoyas, Spain (pers. comm.). In Museum consisting of Upper Jurassic outcrops in Liaoning addition, Gary Poore, of Victoria, Aus- Province (Fig. 1) of the People’s Republic of China tralia and Bill Humphries, Western Australian Mu- and is the third taxon of a series of new crusta- seum, are describing a newly discovered Recent cean species from China to be described by the spelaeogriphacean, said to closely resemble the authors. The first locality represents Jianshangou Potiicoara brasiliensis, from the Pilbara Craton sedimentary intercalation of the Upper Jurassic of Australia (Humphries, pers. comm.). Yixian Formation and is found in Jianshangou The phylogeny of this enigmatic order will be The second discussed in detail later in this village, Chaomidianzi, Beipiao County. some paper. How- the different will be used than that locality represents slightly younger Dakangpu ever, a approach sedimentary intercalation, also from the Yixian For- of Pires (1987) who conducted a phylogenetic mation, and is located in Dakangpu village, Yixian analysis of the orders composing the Superorder County (Chen, 1988; Chen et ah, 1980). Peracarida. We will use the cladistic method to Spelaeogriphacean research dealing with new suggest possible relationships within the order. In I- T'g- of collection sites of (inset: with Locality map Liaoningogriphus quadripartitus, highlighted by pointers China, map area shown as a black rectangle (highlighted by small pointers)). Downloaded from Brill.com10/11/2021 09:56:06AM via free access Contributions to Zoology, 68 (1) - 1998 21 will include members no visible of Para- addition, we representative appendages (see descriptions paratypes). NIGP 126270A/B: lateral view, thorax, abdomen and of the peracaridan orders in this analysis to deter- types, tail fan, with pleopods; NIGP 126275-1: dorsal view, carapace mine the ordinal relationships suggested by our and thorax with antennae and antennules; NIGP 126278A/B- data. 2: lateral view, (incomplete) head, thorax and (incomplete) abdomen, with partial thoracopods; NIGP 126286-1 and 2: ventral view, abdomens with incompletetail fans and pleopods; Systematic palaeontology NIGP 126348: dorsal abdomen and tail fan, partial pleopods; and NIGP 126352: ventral view of complete (juvenile?) ani- mal. Also figured specimens 126275-8; 126276-8-1,2; 126278A- Class Malacostraca Latreille, 1806 1,3,4. All material is housed at the Nanjing Institute ofGeology Subclass Eumalacostraca Grobben, 1892 and Palaeontology(abbreviated here asNIGP), Academia Sinica, Peracarida 1904 Superorder Caiman, the People’s Republic of China. Order Hemicaridea Schram, 1981 Suborder Spelaeogriphacea Gordon, 1957 Additional material.-NIGP 126271: 1-5, NIGP 126272-126274, NIGP 126275: 2-9, NIGP 126276: 1-7, NIGP 126277, NIGP Family Spelaeogriphidae Gordon, 1957 126278A/B: 5-12, NIGP 126279: 1-20, NIGP 126280-126281, NIGP 126282: 1-2, NIGP 126283-126285,NIGP 126286: 3-6, NIGP 126287A/B,NIGP 126349. Liaoningogriphus Shen, Taylor & Schram, gen. nov. Localities and stratigraphy. - Jianshangousedimentary intercala- Diagnosis. - with shallow smooth ‘op- Carapace tion, Upper Jurassic Yixian Formation from Jianshangou vil- tical’ grooves and smoothly rounded lateral mar- lage, Chaomidianzi, Beipiao County, Liaoning Province; and gins extending laterally to third thoracomere, with Dakangpu sedimentary intercalation. Upper Jurassic Yixian second Formation from Dakangpu village, Yixian County, Liaoning thoracomere exposed via a mediodorsal Province (see Fig. 1). indentation; pleomeres 1-5 large, well developed and setose, with large, subequal, subrectangular Description. - The body is elongate and cylindri- protopod, ovoid endopod and ovoid, two-segmented cal and is approximately 3-4 times as long as it is exopod; subtriangular telson with pair of short, wide, with a maximum observed length of >1.75 medial terminal spines; well-developed setose Table PI. The makes cm (see I, Ib). carapace up uropods with rectangular protopod, large, ovoid approximately one fifth of the total body length endopod and exopod of two subequal segments. (see Table I) and is undecorated, thinly sclerotized and covers the head and most of the first two - The Etymology. genus name Liaoningogriphus 126271 It thoracomeres (NIGP -1). possesses a very is derived from the name of the region, Liaoning short (<0.5 mm), broadly rounded rostrum. The Province, from which this species has been col- lateral margins are smoothly rounded at lected, carapace and ‘griphos’ (‘something complicated’), both the anterolateral and posterolateral ends of both to reflect the confusing nature of the pleopods the carapace, in an almost ovoid appear- of this resulting animal and as a dedication to the work of ance in lateral view. Shallow, smooth ‘optical’ Gordon with this group. located between the and grooves are rostrum the A 0.5 anterolateral margins (PI. Ib, PI. Ild). mm

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