Carneyella ulrichi

Classification
Phylum: Echinodermata
Class: Edrioasteroidea
Order: Isorophida
Family: Hemicystitidae
Genus:Carneyella
Species: Carneyella ulrichi (Bassler & Shideler, 1936)

Stratigraphic Occurrences

C.ulrichi_strat

Geographic Occurrences

Map point data provided by iDigBio.

Stratigraphic Description

Sequences (Formations)

  • C2 Sequence (Bellevue)

Identification in Hand Sample

  • Large Carneyella
  • Circular theca covered with large pustules
  • Interambulacra divided by 5 curved ambulacra
  • Three very large primary oral plates
  • Differs from C. pliea by presence of large nodes covering theca

Carneyella ulrchi from Bellevue Formation of unknown location (CMCIP 50068)

Published Description

Holland (UGA Strat Lab, 2013):

  • Has large clavate tubercules with acuminate distal extremities, numerous on larger interambulacral and rim plates.

Sumrall (2010) :

  • AMENDED DIAGNOSIS: Carneyella with large pustules on external surface of plates; most cover plates bearing single pustule along abradial margin forming rows parallel to ambulaca.
  • DESCRIPTION: Large Carneyella with domal, circular theca bounded by peripheral rim theca covered with large organized pustules, and interambulacra divided by five curved ambulacra (Fig. 5). Oral area centered at junction of ambulacral system, dominated by three very large primary oral plates; largest primary oral plate centered in CD interambulacral area, roughly triangular in outline with point directed posteriorly, anterior margin slightly chevron-shaped indented along midline where posterior plate articulated to paired anterior primary oral cover plates; ornamented typically with three large pustules along posterior margin, but variation is noted (Figs. 4.1, 5.3, 5.15), smaller accessory pustules may be present along midline with maturity, high sharp ridge present along suture with other primary oral plates (POP); two smaller POPP positioned in AE and AB interradii; wide-lathe shaped, articulated with lateral bifurcation plates (LBP) without intervening anterior shared cover plates, each with large node near distal edge of plate addition of smaller more proximal node with maturity, contact edges adjacent to other POPP with high sharp edge; all POPP with wide, well devleoped intrathecal extensions; LBPP relatively small form the branching points of the hared ambulacra; right and left LBPP offset to anterior (Figs. 4.1, 5.3). Hydropore located in proximal right CD interambulacrum, formed from inlarged first right cover plate of C ambulacrum, and elongate hydropore oral; hydropore oral in contact with first two to three right cover plates of C ambulacrum (Fig. 4.1). Ambulacra branch from peristome in 2-1-2 pattern; A, B, and D ambulacra plates with biserial cover plates starting on the left is viewed proximal to distal; C and E cover plates start on right (Fig. 4.1); first right cover plate on amblacrum C greatly enlarged and associated with hydropore oral; first left cover plate on D ambulacrum somewhat enlarged; ambulacra all curved all counter clockwise except C clockwise (Fig. 5.5). Ambulacra curve evenly throughout length to peripheral rim, terminate bluntly just beyond adjacent interambulacrum; cover plates narrow, lathe-shaped, biserial with extensive intrathecal extensions (Fig. 5.14), with strong ornament, single large node along the abradial edge of exposed position of cover plate, adradial tip with elongate ridge; intrathecal extensions long extending nearly as far as exposed portion of plate, narrow and tapering with blunt terminus forming distinct gap between adjacent plates (Fig. 5.14); intrambulacral extensions large, scroll-shaped, extending anteriorly beyond edge of exterior portion of plate (Fig. 5.11); cover plate width on interior of curved ambulacrum much narrower than exterior width. Interambulacra relatively large, CD largest and BC smallest because of curvature of C ambulacrum; interambulacral plates relatively small, numerous, imbricate in juveniles, becoming nearly adjacent with maturity; each plate with two to ten nodes depending on plate size (Fig. 5.16) nodes evenly distributed across interambulacral areas. Periproct indistinct because of ornament, plates with irregular low conical array of lathe-shaped plates each bearing one or two large nodes. Peripheral rim very wide-plated with eight or nine irregular circlets of highly imbricate plates; most proximal circlets not differentiated form other circlets; proximal circlets with large, transversely elongate, plates becoming much smaller and radially elongate distally; bottom surface of peripheral rim unknown; bottom surface of theca unplated.
  • DISCUSSION: Carneyella ulrichi Bassler and Shideler was previously known from a single specimen USNM S-3964 housed in the U.S. National Museum. This specimen was collected from a nearly railroad cut in approximately the same stratigraphic position. It is comparable in size to the oens described here and attached to a brachiopod. The specimen has been taphonomically slumped toward the D ambulacrum but is otherwise in good condition. Stratigraphically this specimen is comparable to the Maysville slab and shows all of the diagnostic features common to the larger collection described here. Carneyella ulrichi clearly differs from C. pilea (Hall) by the presence of large nodes covering the theca. It differs from C. faberi (Miller) by the much larger nodes and the restriction of nodes to one per cover plate in nearly every case.
  • The distribution of nodes on the interambulacral plates and the peripheral rim is dispersed and variable between specimens. The distribution on the cover plate series is, however, more controlled. in general, there is a single large node at the abradial edge of the exposed portion of each cover plate. In some individuals, these nodes are poorly expressed in some ambulacra (i.e., a ambulacrum of Fi. 5.10). Also, in rare cases, the proximal-most cover plates may have a second node as reported by Bell (1976a) (Fig. 5.18) This may be a maturity factor. The expression of nodes on the primary orals is also fairly consistent between specimens. Nodes are medially plated on the anterior oral plates and along the left argin of the posterior plate though there is some variation (Figs. 4.1, 5.15).
  • ONTOGENY: Little ontogenetic information is available for species on the Maysville hardground. Although a number of very small specimens are present, their poor preservation precludes their use in ontogenetic analyses. For Carneyella ulrichi, ontogeny proceeds in manner detailed by Bell (1976) with small juveniles having straight amulacra (Fig. 3.1) that gradually become more curved throughout ontogeny (Fig. 5.2, 5.12, 5.16). Nodes are present on all of the plates early in ontogeny (Fig. 5.1) and become more pronounced with maturity (Fig. 5.16). Also noted is a general tendency for the number of nodes to increase with age on the primary oral plates, though there is much variation in the expression of this characteristic.
  • Specimens of Carneylla ulrichi Bassler and Shideler described here were collected from the Bellevue Member of the Grant Lake Formation in a set of roadcuts along State Rt. 3071 near Maysville, Mason County, Kentucky.

Dry Dredgers :

  • Carneyella ulrichi looks almost exactly like Carneyella pilea except that the surface is covered with small bumps. Two bumps on each cover plate.