Revision of the genus Clathrina (Porifera, Calcarea) Author Klautau, Michelle Author Valentine, Clare text Zoological Journal of the Linnean Society 2003 2003-09-30 139 1 1 62 https://academic.oup.com/zoolinnean/article-lookup/doi/10.1046/j.0024-4082.2003.00063.x journal article 10.1046/j.0024-4082.2003.00063.x 0024-4082 5432634 CLATHRINA CONIFERA KLAUTAU & BOROJEVIC, 2001 Type locality: Arraial do Cabo , Rio de Janeiro , Brazil . Type: BMNH 1999.9 .16.19 ( holotype /alcohol). Arraial do Cabo (Anjos Beach), Rio de Janeiro , Brazil . Collected by G. Muricy ( 15 November 1987 ) . Citations: Klautau et al . (1994) (as C. primordialis ). Colour: Cormus of preserved specimen is white. Description: Specimens of this species are very similar to those of C. cylindractina , and can easily be mistaken for them. The massive, yet delicate, cormus is formed of large, irregular and loosely anastomosed tubes and oscula are spread throughout. No water-collecting tubes are present. The cormus comprises a few tubes spread on rocks when the sponge is still very young. The skeleton has no special organization and comprises only one kind of spicule, the triactine. Triactines are equiangular and equiradiate and their actines are straight and conical, with blunt tips ( Fig. 13B ). C. conifera is sciaphilous, being frequently found under rocks or other animals, such as other sponges, tunicates and soft corals. Figure 13. Clathrina conifera . Triactines. Scale bar = 100 Mm.

Length (Mm)		Width (Mm)
min	mean	s	max	mean	s	n
Triactines	62.5	77.3	± 9.3	97.5	9.0	± 1.0	30

Remarks: This species, which we now call C. conifera , was first described in a previous article ( Klautau et al ., 1994 ) as C. primordialis ( Haeckel, 1872 ) . In his description, Haeckel did not give the type locality of this species, but mentioned several places at which it was found, including Rio de Janeiro . As he had not elected a holotype , and as the syntypes seemed to have disappeared, we have selected the specimen from Arraial do Cabo matching his description as the neotype of C. primordialis , and suggest that Rio de Janeiro should become the locus typicus of this species. However, for the current work, we did manage to locate a syntype of C. primordialis in PMJ . It was collected from Lesina (Adriatic) , which means that the type locality of this species should be considered as Lesina and not Rio de Janeiro . Although there are similarities between the description given by Haeckel and the specimens from Arraial do Cabo , we decided not to consider our specimens as C. primordialis . These morphologically simple species of Clathrina seem to be a complex of species that should be split into new species. Considering our previous results with Clathrina populations from the Mediterranean and from the Atlantic, we name the specimens from Arraial do Cabo with conical actines as C. conifera , to distinguish the species from its sibling C. primordialis from the Adriatic Sea. Besides similarities with C. primordialis , C. conifera is also morphologically similar to C. cylindractina , another species from Arraial do Cabo . However, they can be distinguished by the size and shape of their actines: C. cylindractina has larger spicules than C. conifera . However, the most important morphological difference between them relates to the shape of their actines. In C. cylindractina , the actines are cylindrical or only slightly conical, while in C. conifera they are markedly conical.

Length (Mm)		Width (Mm)
min	mean	s	max	mean	s	n
Triactines	67.5	87.3	± 9.5	102.5	10.0	± 0.5	25
Tetractines	72.5	94.5	± 9.8	115.0	9.8	± 1.0	30
Apical actine	32.5	81.8	± 39.5	155.0	5.0	± 1.3	30
Diactines	173.4	503.9	± 145.9	816.0	31.6	± 8.2	30

Both populations have already been subjected to allozyme analysis ( Klautau et al ., 1994 ) and, although living in sympatry, it was confirmed that no gene flow occurs between them, indicating that they are distinct species.