Chrispaulia spinosa, Gale & Jagt, 2021

Gale, Andy S. & Jagt, John W. M., 2021, The fossil record of the family Benthopectinidae (Echinodermata, Asteroidea), a reappraisal, European Journal of Taxonomy 755, pp. 149-190 : 176

Chrispaulia spinosa sp. nov.

urn:lsid:zoobank.org:act:4C003A9F-1F91-44BC-91AB-2910B8EA756A

Fig. 13D–E, H–O

Diagnosis

Chrispaulia in which distal inferomarginals bear an oblique row of large, bifid spine attachment sites, which carried long, flattened spines.

Etymology

Latin for ‘bearing spines’, in reference to the row of spine attachment sites on distal inferomarginals.

Material examined

A distal arm fragment ( Nds LH 105.107 ), comprising five marginal pairs, with articulating spines preserved, is the holotype; it is from the lower Hauterivian ( Endemoceras amblygonium ammonite Zone) at Engelbostel near Hannover (northern Germany). Paratypes ( NHMUK PI EE 17998–18004 ) are 35 marginal ossicles and a single oral ossicle from the upper 3 metres of the Tealby Clay (Hauterivian) at Nettleton, Lincolnshire (United Kingdom).

Description

Arms elongated, narrow, tapering slowly ( Fig. 13D–E ); proximal superomarginals tall, block-like, bearing a single, abactinally directed, crater-like spine base. Central region of external face narrow, poorly defined, lateral surfaces broad with small rugosities for attachment of tiny cribriform spines ( Fig. 13H–I, N ; spines still articulated in Fig. 13D ). Distal superomarginals with or without an abactinally situated, distally directed large spine base ( Fig. 13I–J ), rugose ( Fig. 13D ) or smooth ( Fig. 13I–J ). Distal infero- and superomarginals thin, imbricating proximally; distal inferomarginals with oblique row of large, bifid spine bases, which bore flattened, lanceolate spines ( Fig. 13D ). Sharply defined grooves for cribriform organs between each infero-/superomarginal pair. Oral ossicle ( Fig. 13O ) with broad actinal face, bearing large rugosities for attachment of sos; large elongate oradm, low, broad apophyse.

Remarks

Chrispaulia spinosa sp. nov. differs from its congeners in its possession of 3–4 bifid spine pits on distal inferomarginals.

Figures

Fig. 7 (next page). A–J. Jurapecten infrajurensis sp. nov., various ossicle types (paratypes). A, H. Ambulacrals, in lateral and actinal aspects, respectively (SNSB-BGSP2020XLV 21,SNSB- BGSP2020XLV 28). B, E–F. Adambulacrals, in actinal and abactinal views (SNSB-BGSP2020XLV 22, SNSB-BGSP2020XLV 25–26). C, G, J. Superomarginals, in lateral views (SNSB-BGSP2020XLV 23, SNSB-BGSP2020XLV 27, SNSB-BGSP2020XLV 30). D, I. Inferomarginals, in lateral views (SNSB-BGSP2020XLV 24, SNSB-BGSP2020XLV 29). — K–Y. Jurapecten hessi Gale, 2011. K, P, U. Adambulacral ossicles. K. Abactinal view (NHMUK PI EE 17996). P. NHMUK EE 13598 (the original of Gale 2011a: pl. 19 fig. 11). U. NHMUK EE 13599, the original of Gale (2011a: pl. 20 fig. 12). L. Circumoral ossicle (NHMUK EE 13605, the original of Gale 2011a: pl. 20 fig. 13). M–N. Ambulacral ossicles, in actinal and abactinal views, respectively (NHMUK EE 13595–13596, the originals of Gale 2011a: pl. 19 figs 8–9). O. Ambulacral, in proximal/distal view (NHMUK 13597). Q–S. Superomarginal ossicles (NHMUK EE 13601–13602; the originals of Gale 2011a: pl. 20 figs 6–7). T, V–W. Inferomarginals (NHMUK EE 13600, EE 13603–13604, EE 13608, the originals of Gale 2011a: pl. 20 figs 5, 8, 16). X–Y. Oral ossicles (NHMUK EE 13606– 13607, the originals of Gale 2011a: pl. 20 figs 10, 14). Provenance: A–J. Upper Toarcian–lower Aalenian (possibly aalensis ammonite Zone), Quedlinburg (Landkreis Harz, northern Germany; see Hess 2014). K–Y. Upper Oxfordian (Couches d’Effingen, bifurcatus ammonite Zone, stenocycloides ammonite Subzone), Savigna, near Orgelet, Département du Jura, France (Gale 2011b). Abbreviations: d = distal; p = proximal. See Fig. 3 for detailed morphological terminology. Scale bars: A–J = 0.2 mm; K–Y = 0.5 mm.