Revision of the subgenus Neopsacas (Hexactinellida, Rossellidae, Crateromorpha) with the description of new species and subspecies
Author
Menshenina, Larisa L.
Author
Tabachnick, Konstantin R.
Author
Janussen, Dorte
text
Zootaxa
2007
1463
55
68
journal article
10.5281/zenodo.176494
d38bdbd0-29f5-4f33-b8c1-a409d7b60112
1175-5326
176494
Genus:
Crateromorpha
Gray
in
Carter, 1872
Subgenus:
Crateromorpha (Neopsacas)
Tabachnick, 2002
Synonymy
Crateromorpha
(
Neopsacas
)
Tabachnick, 2002
: 1479
.
Type
species
Crateromorpha
(
Neopsacas
)
variata
Tabachnick, 2002
(by primary designation).
Differenciated diagnosis
Crateromorpha
with hypodermal-hypoatrial spicules having spines near the spicule centre.
Diagnosis, revised
Body is bell-like or ovoid, basiphytous with long peduncle. The choanosomal skeleton is composed chiefly of diactins, rarely tauactins, stauractins and pentactins. The spicules of the peduncle are diactins fused to each other by synapticula. Dermalia and atrialia are similar to each other and contain mostly pentactins and diactins or diactins only. Hypodermalia and hypoatrialia (when present) are mostly pentactins sometimes hexactins with spines near the spicule centre. Microscleres are various in different species: discoidal, spiny spicules with 1-(usually 5)–6 rays; drepanocomes; hexasters and hemihexasters with discoidal, onychoidal and oxyoidal outer ends.
Remarks
Discovery of new species have led to further overlap of features between
Crateromorpha (Neopsacas)
and other subgenera of
Crateromorpha
.
Differences in microsclere composition have become less distinctive, and now the most important feature to distinguish
Crateromorpha (Neopsacas)
from other subgenera is presence of spines situated close to the spicule centre in hypodermal and hypoatrial hexactins. Dermal and atrial spicules are rare in some specimens and do not seem to form continuous layers in
Crateromorpha (Neopsacas)
.