Clathrina sagamiana (Hozawa, 1929)

Klautau, Michelle & Valentine, Clare, 2003, Revision of the genus Clathrina (Porifera, Calcarea), Zoological Journal of the Linnean Society 139 (1), pp. 1-62 : 38-39

CLATHRINA SAGAMIANA ( HÔZAWA, 1929)

Original name: Leucosolenia sagamiana Hôzawa, 1929

Type locality: Odawara , Sagami Sea, Japan .

Type: Tokyo Sci. Fac. Spec. N ∞. 39. (holotype /alcohol). Front of Omeit water, Odawara , 120 Hine. Sagami Sea, Japan, 171 m depth. By hand with bamboo gear by Ijima (1 August 1895) .

Citations: Tanita (1942, 1943); Burton (1963).

Colour: Preserved holotype is white.

Description: The holotype is completely fragmented, but some of the fragments are still attached to the Alcyonaria mentioned in the original description by Hôzawa. According to Hôzawa, the largest individual was provided with a terminal osculum. However, it is no longer possible to recognize the organization of the cormus ( Fig. 30A ).

The skeleton comprises two populations of equiangular and equiradiate tetractines ( Fig. 30B ), but there are also sagittal tetractines. Triactines are rare. Diactines are also present ( Fig. 30B ). Actines are conical, straight and sharp. The apical actine of the tetractines is conical, smooth and has almost the same length as the facial actines. Diactines are fusiform and slightly curved. They are projected through the surface of the tubes.

Remarks: According to the original description, the holotype was attached to a branch of Alcyonaria, as we confirmed. The size of the spicules in the original description was:

Although Hôzawa had not discriminated between the two populations of tetractines, he mentioned in his original description that the ‘dermal (tetractines) are usually slightly larger than the deep ones’.

C. sagamiana differs from C. reticulum in the size of its spicules (which are shorter in C. reticulum ), in the shape of the diactines, which are not arrow-shaped in C. sagamiana , and in the shape of the actines of the triactines and tetractines, which is cylindrical in C. reticulum and conical in C. sagamiana , and also by the presence of a second population of tetractines in C. sagamiana .

The differences between C. sagamiana and C. contorta are mainly in the shape of the apical actine of the tetractines, which is conical in C. sagamiana and cylindrical in C. contorta , as well as in C. reticulum . In relation to C. laxa , the absence of the large tetractines, the diameter of the apical actine and of the tetractines, and the length of the actines of the tetractines are enough to differentiate it from C. sagamiana .

Figures

Figure 30. Clathrina sagamiana. A, photograph of the holotype (¥ 10). B, skeleton comprising tetractines and diactines (arrow). Scale bar = 100 Mm.