Paracaudina Heding 1932
Creators: name: O'Loughlin, P. Mark
name: Barmos, Shari
name: VandenSpiegel, Didier
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Echinodermata
Holothuroidea
Molpadida
Caudinidae
Paracaudina

description: Paracaudina Heding, 1932
Figures 1f, 5c–e, 7, 8, 12a, b
Pseudocaudina Heding, 1931: 283.
Paracaudina Heding, 1932: 455–456.
Type species. Molpadia chilensis Müller, 1850 (subsequent designation by H. L. Clark 1935).
Other included species. Paracaudina ambigua O’Loughlin and Barmos sp. nov.; P. australis (Semper, 1868); P. bacillis O’Loughlin and Barmos sp. nov.; P. coriacea (Hutton, 1872); P. cuprea O’Loughlin and Barmos sp. nov.; P. delicata Pawson and Liao, 1992; P. keablei O’Loughlin and Barmos sp. nov.; P. luticola Hickman, 1962; P. chilensis obesacauda (H. L. Clark, 1908); P. tetrapora (H. L. Clark, 1914); P. tripoda O’Loughlin and Barmos sp. nov.
Diagnosis. Cylindrical form, smooth or wrinkled body wall; tentacles 15, each with 2 pairs of digits (figs 1f, 5c); posterior end of body with caudal taper or discrete thin tail; tail may be short or long; 5 radial triangular non-calcareous anal valves, each with up to 4–5 pairs of marginal digitiform papillae, terminal ones longest (fig. 5d); radial plates of calcareous ring with two anterior lateral low blunt projections, one with small notch, posterior digitiform prolongation about half the length of the plate, prolongation divided by terminal notch of variable depth or deeper division (fig. 12a); interradial plates with anterior central blunt point, posterior end truncated (fig. 12a); dorsal short to long tubular stone canal with terminal madreporite, free in coelom or attached to pyloric mesentery (specimen NMV F174894); single ventral, elongate, tubular to globular polian vesicle, usually with dark reddish-brown colouration; longitudinal muscles broad, flat, with distinct longitudinal division (fig. 5e); retractor muscles formed by pair of in-turned outer margins of divided longitudinal muscles (fig. 5e); gonad tubules usually branched, in tufts on each side of dorsal mesentery (fig. 5e); right branch of respiratory tree extending in the coelom to the calcareous ring; ossicles may be concave or flat, thick crossed and knobbed cups, thick knobbed perforated plates, octagonal plates with large central perforation and cross or tripod bridging one side and sometimes square the other side (figs 7, 8, 12b), perforated smooth and knobbed and spinous plates with variably developed secondary layering, and irregular rods; ossicles never tables; phosphatising of ossicles and calcareous ring may occur, and a red to brown to yellow pigment may occur in the body wall.
Remarks. A comprehensive diagnosis of genus Paracaudina Heding, 1932 is provided to avoid diagnoses of species with repetition of characters that all have in common. We recognise that some of the characters listed in this diagnosis of Paracaudina are shared with other genera and at family and possibly order level.
description: Published as part of O'Loughlin, P. Mark, Barmos, Shari & VandenSpiegel, Didier, 2011, The paracaudinid sea cucumbers of Australia and New Zealand (Echinodermata: Holothuroidea: Molpadida: Caudinidae), pp. 37-65 in Memoirs of Museum Victoria 68 on page 39, DOI: 10.24199/j.mmv.2011.68.03, http://zenodo.org/record/10666040