Amphimedon brevispiculifera ( Dendy, 1905 )

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 : 16-17

Amphimedon brevispiculifera ( Dendy, 1905)

Fig. 9

Pachychalina brevispiculifera Dendy, 1905: 149 , pl 10 fig. 7.

Material examined

PONTA DO OURO • 2 branches, about 4 cm long, alcohol preserved; 26°49′55.65″ S, 32°53′13.417″ E; Three Sisters; 23.9 m deep; 21 Feb. 2017; Cerrano leg.; PO65 .

Description

The live sponge is arborescent, with flattened branches often anastomosing ( Fig. 9A ); oscules are numerous and concentrated on the upper margin of the branches ( Fig. 9A ). Light purple in vivo, the specimen conserved in alcohol is pale yellow; the surface is smooth, the consistence is firm and elastic. The preserved sample consists of two small fragments; the biggest being a small branch about 4 cm long and 1.5 cm thick.

SKELETON. Ectosome ( Fig. 9B ) formed by multispicular fibers, rich in spongin, with the diameter ranging between 20 and 75 μm, creating irregular, rounded meshes of 100–200 μm. Echinating spicules, at the end of the choanosomal primary fibers, protrude at the nodes. Choanosome ( Fig. 9C ) consists of multispicular primary fibers as well as multispicular secondary fibers, of about the same thickness (20–90 μm in diameter), forming rectangular meshes (average of 100 ×175 μm).

SPICULES. Short, stout and sharp oxeas, 80–(88.5, 4.4)–95×2.5–(2.75, 1.3)–3 μm ( Fig. 9D ).

Remarks

Out of 57 species of the genus Amphimedon , 30 are recorded in the Indo-Pacific Ocean ( Van Soest et al. 2019). The examined specimen fits with A. brevispiculifera described from the Gulf of Manaar. They share the same general morphology, disposition of the oscules and the short dimension of the spicules (100 × 5.5 μm); the species name “ brevispiculifera ” means ‘with short spicules’. All the other species of Amphimedon in the Indo-Pacific Ocean are characterized by longer oxeas.

The present specimen is apparently morphologically similar to the sponge recently recorded by Samaai et al. (2019) in South Africa and named Callyspongia (Cladochalina) diffusa sensu Samaai et al. (2019) .

This species was previously known only from South India and Sri Lanka ( Laccadive Sea); thus, it is the first record since its original description and a new record for the studied area.

Figures

Fig. 9. Amphimedon brevispiculifera (Dendy, 1905). A. Specimen PO65 in situ. B. Ectosomal skeleton. C. Choanosomal skeleton. D. Oxea.