Axinyssa Lendenfeld, 1897

Ubare, Vibha V. & Mohan, P. M., 2018, New Records and Range Extensions of Some Marine Sponges (Porifera: Demospongiae and Homoscleromorpha) from the Andaman Islands, India; Part of the Indo-Burma Biodiversity Hotspot., Zoological Studies 57 (3), pp. 1-15 : 10-11

Genus Axinyssa Lendenfeld, 1897 Axinyssa mertoni ( Hentschel, 1912)

( Figs. 12 and 13 )

Synonyms: Amorphinopsis mertoni ( Hentschel, 1912) (genus transfer)

Axinyssa pitys (de Laubenfels, 1954) (junior synonym)

Ciocalypta mertoni Hentschel, 1912 (genus transfer)

Pseudaxinyssa pitys de Laubenfels, 1954 (genus transfer and junior synonym)

Material examined: 1 ex., DOSMB 00204, India: Andaman and Nicobar Islands: Middle Andaman: Mayabunder, Coll. Vibha Ubare, 29.vii.2014.

Description: It has a massive-flanged shape with fistulae arising from the basal buried portion of the sponge ( Figs. 12 A-B). The fistulae are 1.7- 1.9 cm long and 0.7-0.9 mm thick with serrated margin. The basal portion is fully buried in the sand and it measures 9 × 5 × 4 cm. It is very soft and whitish in colour, but changes to light gray after preservation. The oscules are inconspicuous. The surface is soft, compressible, fragile and somewhat tough to remove.

Spicules: Megascleres-only oxea ( Fig. 12C ) is present. It is smooth, hastate, and long; measures 289.0-719.0 × 6.5-7.0 μm. Microscleres The choanosomal skeleton shows plumose to halichondroid arrangement with multispicular tracts running longitudinally and close to each other. It comes out from the surface as plumose brushes (Alverez and Hooper 2011) ( Figs. 12 D-G).

Habitat: Present in the sandy substratum.

D i s t r i b u t i o n: I n d i a: M i d d l e A n d a m a n: Mayabunder (Present study). Elsewhere -Arafura Sea ( Hentschel 1912), Indian Ocean ( Alvarez and Hooper 2011), Indonesia ( Hentschel 1912), Palau ( Hooper and van Soest 2002) and West Caroline Islands ( Laubenfels 1954, Bergquist 1965) ( Fig. 13 ).

Remarks: This species has been reported from the Indian region through this study.

Figures

Fig. 12. Axinyssa mertoni (Hentschel, 1912). (A) Specimen after preservation. (B) Close view of fistular structure. (C) Oxea. (D) Longitudinal section. (E) Longitudinal section. (F) Transverse section. (G) Transverse section.

Fig. 13. Geographical extension of Axinyssa mertoni (Hentschel, 1912). © 2018 Academia Sinica, Taiwan