Mycale (Rhaphidotheca) coronata
Creators: name: Van, Rob W. M.
name: Aryasari, Ratih
name: De, Nicole J.
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Porifera
Demospongiae
Poecilosclerida
Mycalidae
Mycale
Mycale coronata

description: Mycale (Rhaphidotheca) coronata (Dendy, 1926)
Fig. 114a
Sceptrospongia coronata Dendy, 1926: 6, pl. I figs 1–8; Burton 1928: 121, text-figs 4–5.
Mycale (Rhaphidotheca) coronata; Van Soest & Hajdu 2002: 684, fig. 14.
Summary description (after Dendy 1926; Burton 1928; Van Soest & Hajdu 2002). The sponge is subspherical, attached to deep-water corals. The larger of the two specimens (the holotype cf. Burton (1928), which is however not further identified by Dendy, so in fact is a lectotype) measuring 1.5 cm in diameter. Surface hispid. Oscules slit-like. Color (in alcohol) yellowish grey. For the skeleton and the spicules we reproduced the illustrations of Burton (1928), text-figure 4 and 5, cf. our Fig. 114. The ectosomal skeleton is a confused tangential layer of normal mycalostyles upon which are single erect exotyles arranged perpendicularly, heads embedded in the ectosomal layer, giving the sponge the hispid surface. The choanosomal skeleton has thick megasclere tracts radiating from a confused interior spicule mass towards the surface. In between the radial tracts are numeorous microscleres and loose megascleres. Spicules normal mycalostyles, variable in shape, averaging 360 x 13 µm, exotyles (dubbed ‘stephanotyles’ by Dendy), same size as the mycalostyles, anisochelae I 75 µm, anisochelae II 27 µm, anisochelae III 15 µm, sigmas I 45 µm, sigmas II 18 µm, trichodragmas 15–45 x 9 µm.
Distribution. Arabian Sea, 16.6667°N 71.8883°E, also Andaman Islands, approx. 12.88°N 92.62°E, depth of lectotype 1134 m, paralectotype 81– 486 m.
Comments. The exotyles are peculiar in having a spined polyaxone ending, neatly inbetween the globular exotyles of Mycale (Rhaphidotheca) marshallhalli (Kent, 1870) and the flattened cup-like exotyles of Mycale (Rhaphidotheca) loricata (Topsent, 1896). The polyaxone ending of the exotyles is similar to the endings found in non-exotyle megascleres of Mycale (Paresperella) moluccensis and M. (P.) sceptroides sp.nov. (cf. above, Figs 109a, 111a).
The type material consisting of two specimens from quite distant localities (Arabian Sea and Andaman Islands) is very casually treated by both Dendy and Burton. Dendy did not indicate in his publication which of the two specimens was the holotype, and Burton subsequently described the ‘holotype’ (which is thus in fact a lectotype), which presumably is the specimen from the Arabian Sea as this is the first specimen mentioned (Indian Museum P. 308).
Global diversity and distribution of the subgenus Mycale (Rhaphidotheca)
We queried the World Porifera Database (Van Soest et al. 2020) to arrive at the current tentative estimate of known accepted species, which numbers 5. Their distribution over the world oceans summarized as the numbers of species found in Marine Ecoregions of the World (cf. Spalding et al. 2007) is presented in Fig. 115. The subgenus is common in northern colder waters, with a few penetrating into the tropics.
description: Published as part of Van, Rob W. M., Aryasari, Ratih & De, Nicole J., 2021, Mycale species of the tropical Indo-West Pacific (Porifera, Demospongiae, Poecilosclerida), pp. 1-212 in Zootaxa 4912 (1) on pages 176-177, DOI: 10.11646/zootaxa.4912.1.1, http://zenodo.org/record/4450930