Oceanapia ramsayi ( Lendenfeld, 1888 )

Calcinai, Barbara, Belfiore, Giuseppe, Pica, Daniela, Torsani, Fabrizio, Palma, Marco & Cerrano, Carlo, 2020, Porifera from Ponta do Ouro (Mozambique), European Journal of Taxonomy 698, pp. 1-56 : 19-20

Oceanapia ramsayi ( Lendenfeld, 1888)

Fig. 11

Rhizochalina ramsayi Lendenfeld, 1888: 188 , pl. 3.

Material examined

PONTA DO OURO • 1 dried fragment of about 6 ×1.5× 2 cm; 26°49′17.512″ S, 32°53′42.5″ E; Kev’s; 17 m deep; 20 Nov. 2015; Cerrano leg.; PdO27 • 1 small fragment of about 3 ×1× 1 cm; 26°49′17.512″ S, 32°53′42.503″ E; Kev’s; 17 m deep; 20 Nov. 2015; Cerrano leg.; PdO28 .

Description

Live sponge globular-massive, with oscular tubes arising from the upper surface ( Fig. 11 A–C). The two specimens had distinct colors in life: bright red on the exterior and yellow inside ( Fig. 11 A–B), and dark brown on the exterior and light brown inside ( Fig. 11C ). Both dried samples are dark brown, firm and with a smooth surface.

SKELETON. Ectosome ( Fig. 11D ) constituted of a reticulation of fibers, 30–100 µm in section, forming oval meshes of 350–400 µm of diameters and a secondary sub-isodictyal network of single oxeas. Choanosome formed by thick fibers of spicules, 30–50 µm in section, forming irregularly rounded meshes, 180–380 µm.

SPICULES. Slightly curved oxeas ( Fig. 11E ), 130–(156.7, 11.7)–170× 2.5–(6.2, 1.7)– 10 µm, often with slightly mucronate tips.

Remarks

The samples belong to the genus Oceanapia Norman, 1869 , considering the numerous fistulae on the surface and the general skeleton structure. The genus includes 95 species, 75 of them from the Indo- Pacific Ocean ( Santos Neto et al. 2018). The skeleton, spicule size and general morphology fit the original description of Oceanapia ramsayi Lendenfeld, 1888 from Australia. The holotype was described as yellow, while other, subsequent records of this species report a red color, such as in Itampolo, Madagascar ( Bensemhoun et al. 2008) and brown in Port Jackson, Australia (Hallman 1914). Moreover, Hallman pointed out that his specimen, different from the holotype, was devoid of stout, central tubes, although it occurs with the examined material from Mozambique. The species is also known from the east coast of South Africa ( Schleyer et al. 2006).

Figures

Fig. 11. Oceanapia ramsayi Lendenfeld, 1888. A–B. Red specimen in situ (PdO27); in B a fresh cut highlights the yellow choanosome. C. Brown specimen (PdO28). D. Choanosomal skeleton. E. Oxeas and magnification of a tip.