Five new genera and two new species of unstalked crinoids

Abstract

In revising the genera and species of the large comatulid family Antedonidae, it was found that a more precise definition of certain generic groups was desirable. This is made possible by the creation of three additional genera the recognition of which will assist in bringing out more clearly the true interrelationships of the species in the groups concerned. In addition to these three genera there are described herein a new genus based upon a hitherto undescribed species from the northeastern Pacific and a genus that has long been used by the author but never formally diagnosed. A small West Indian comatulid recorded from the Blake collection by Dr. P. H. Carpenter as Antedon hagenii was for a long time a mystery, as none of the specimens were received by Hartlaub when, after Carpenter's death, the Blake collection was sent to him. This now turns out to be a species quite dift'erent from Coccometra hagenii, and it is described below as Compsometra nuttingi. It is assigned to the genus Compsometra with some misgivings, but until more adequate and more extensive material is available it seems better to place it here than to create a new genus for it.

Phylogeny of Comatulidae (Echinodermata: Crinoidea: Comatulida): A new classification and an assessment of morphological characters for crinoid taxonomy

“…We were able to include fewer than half of the described species of Anneissia n. gen., Comanthus, and Phanogenia, with most of the missing taxa occurring in more northern IWP areas (e.g., Japan). The four genera for which sequence data are lacking-Palaeocomatella (3 species), Rowemissia (1 species), Comatulides (1 species), and Comatilia (1 species)-are known from depths greater than 100 m (A.H. Clark, 1908bClark, , 1909dClark, , 1911aClark, , 1931McKnight, 1977;Messing, 1984Messing, , 2001Messing, , 2007Messing and Dearborn, 1990;Messing et al, , 2000 and are relatively rare in collections. Likewise, 13 additional species of Comissia are recorded from depths chiefly greater than 100 m in the IWP (A.H. Clark, 1931;Hoggett and Rowe, 1986;Kogo and Fujita, 2014;McKnight, 1977;Rowe and Gates, 1995), and Neocomatella europaea A.H. Clark (1913), the deepest member of the family, occurs in 400-1700 m in the northeastern Atlantic (A.H. Clark, 1931).…”

“…7D). (2) Comatulini consists of Comactinia and Comatula, an arrangement not previously found with molecular data. A.H. Clark (1909c) initially treated both as Comactiniinae (plus Cominia [=Comatulides] and later Comatulella) ( Table 1) based on their lack of aboral cirral processes, extremely short and distally produced genital pinnulars, and, when present, post-IBr brachitaxes of two ossicles (Fig. 7B).…”

“…Among extant articulates, over 80% of the $650 accepted species belong to order Comatulida (Rouse et al, 2013;Hemery et al, 2013), most members of which shed the postlarval stalk and take up a non-sessile existence as feather stars (Holland, 1991;Haig and Roux, 2008). Contemporary taxonomy of extant crinoids dates chiefly from 1907 to 1909, when A.H. Clark (1907aClark ( , 1908aClark ( ,b, 1909a described 75 genera and 17 family-level taxa, chiefly feather stars. Although a few families and genera have since been revised (e.g., Hoggett and Rowe, 1986;(Fig.…”

“…A.H. Clark (1908b later fixed Comatula solaris Lamarck, 1816, as the type of Comatula. Clark used Comatulidae in 1908c, but subsequently(Clark, 1908a) changed it to Comasteridae (with no diagnosis). In 1931, A.H. Clark noted, with reference to his 1908a paper, ''The family Comasteridae as understood in 1908 included the genera Comatula and Comaster.…”

“…Orbigny, 1852) to include the genus ComatulaLamarck, 1816. A.H. Clark (1908b later fixed Comatula solaris Lamarck, 1816, as the type of Comatula.…”