A revision of the supraspecific classification of the subclass Calcaronea (Porifera, class Calcarea) Author Borojevic, Radovan Departamento de Histologia e Embriologia, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Caixa Postal 68021, 21941 - 970 Rio de Janeiro (Brazil) radovan @ iq. ufrj. br radovan@iq.ufrj.br Author Boury-Esnault, Nicole Author Vacelet, Jean Centre d’Océanologie de Marseille (CNRS-Université de la Méditerranée, UMR 6540 DIMAR), Station marine d’Endoume, F- 13007 Marseille (France) esnault @ com. univ-mrs. fr jvacelet @ com. univ-mrs. fr text Zoosystema 2000 22 2 203 263 journal article 10.5281/zenodo.5392175 1638-9387 5392175 Genus Kebira Row, 1909 TYPE SPECIES . — Kebira uteoides Row, 1909 by monotypy. DIAGNOSIS. — Lelapiidae with a leuconoid organization. The choanoskeleton has large diactines and spicule tracts consisting of triactines with rudimentary paired actines. The atrial and cortical skeletons are composed of triactines and diactines.

Taxonomy of Calcaronea
ct
cx
cd a ss
ic
as
FIG. 38. — Diagram of the subatrial region of the Kebira skeleton. Abbreviations: a , atrium; as , atrial skeleton; ss , subatrial spicules; ct , choanosomal spicule tracts composed of nail-like triactines; cd , choanosomal diactines.
ec
DESCRIPTION Kebira is clearly related to Grantiopsis with which it shares the nail-form triactines, with reduced paired actines, that are bundled in long tracts. It has a thick wall and a leuconoid organization. The choanoskeleton is supported by giant diactines and
multispicular tracts, which most often maintain the radial organization. The atrial surface is supported by tangential triactines (Fig. 38). Although Row (1909) and Ilan & Vacelet (1993) do not specifically mention subatrial spicules, we have	ct
examined the specimens studied by the latter authors, and found that each choanosomal tract of spicules is anchored at the atrial surface or at the surface of larger exhalant canals, in a single subatrial spicule, just as is observed in Grantiopsis (Fig.37). Both Grantiopsis and Kebira lack the classical articulate choanoskeleton composed of triactine or tetractine spicules. In the thick-walled Kebira , large diactines, apparently derived from the	ct
cortical ones, participate in the formation of the skeleton of the choanosome, in addition to the spicular tracts.	as	a	as
Genus Paralelapia Hôzawa, 1923 TYPE SPECIES. — Lelapia nipponica Hara, 1894 by monotypy.	FIG. 39. — Diagram of a cross-section through the wall of Paralelapia nipponica Hara, 1894 . Abbreviations: a , atrium; as , atrial skeleton; ct , choanosomal spicule tracts formed of tuning-fork-shaped triactines; cx , cortex; ec , exhalant canal; ic , inhalant canal. Scale bar: 60 µm (from Hôzawa 1923).

FIG. 40. — Skeletal arrangement in a longitudinal section of Lelapia australis Gray, 1867 . Abbreviations: a , atrium; dc , dermal cortex; dt , dermal tuft of triactines and slender diactines; fi , spicular fibres formed of tuning-fork-shaped triactines; gc , atrial cortex. Scale bar: 350 µm (from Dendy 1894). DIAGNOSIS. — Lelapiidae with a sylleibid organization of the aquiferous system. The thick cortex is composed of an external layer of triactines and an internal layer of giant longitudinal diactines. The choanoskeleton is composed of radially arranged loose tracts of diapasons, originating proximally from unpaired actines of typical subatrial triactines. A well-developed atrial skeleton consists of tangential tri- and tetractines. DESCRIPTION The relationship of Paralelapia to Lelapia is quite similar to that of Grantiopsis and Kebira . In Paralelapia , the sylleibid aquiferous system and the organization of the choanoskeleton clearly have a radial organization, reminiscent of the Grantiidae . The loose spicular tracts are associat- ed proximally with the subatrial spicules, and the cortical skeleton is well-separated from the choanoskeleton (Fig. 39).