Clathrina rowi Voigt et al., 2017

Van, Rob W. M. & De, Nicole J., 2018, Calcareous sponges of the Western Indian Ocean and Red Sea, Zootaxa 4426 (1), pp. 1-160 : 39-41

Clathrina rowi Voigt et al., 2017

Figures 16a–c , 17a–c

Clathrina rowi Voigt et al., 2017: 14 , fig. 8.

Material examined. RMNH Por. 10002, Saudi Arabia, Jeddah , near Thuwal, Tahlah, 22.25725°N 38.880917°E, scuba, coll. N.J. de Voogd, field nr. THU14/JED209, 13 November 2014 ; ZMA Por. 13446, Israel, Gulf of Aqaba , North Pinnacle, in cave, depth 9 m, scuba, coll. M. Wunsch, field nr. AQ52, 4 July 1998 .

Description. The RMNH Por. 10002 specimen in situ ( Fig. 16a ) is an overall loose mass of intermediate-sized tubuli, provided with several water-collecting tubes ending in oscules. Cormus anastomosed in places to densely connected smaller tubes. Individual tubes 0.4–2 mm in diameter. Color pale beige to dirty white, semi-transparent. Preserved specimen massive due to compression of tubules during preservation and manipulation in transport, 4.5 x 3 cm in lateral expansion, about 1 cm thick, dirty white in color. The ZMA Por. 13446 specimen ( Fig. 17a ) from Aqaba is small. It has a conical, transparent-white cormus with faint purple tinge, consisting of loosely, occasionally more tightly, anastomosed tubules, leading to a prominent single water-collecting tube ending in a wide oscule.

Aquiferous system. Asconoid.

Skeleton. ( Figs 16b , 17b ) Tubuli walls with one to two spicule layers, rather dense in preserved condition.

Spicules. ( Figs 16c , 17c ) Triactines only, neither specimen contained clearly identifiable trichoxeas as reported for some specimens in the type series.

Triactines with thin cylindroconical actines, endings mucronate to shortly pointed, occasionally slightly sagittal, size range limited, in RMNH Por. 10002 it is 68– 124 –151 x 7.5– 9.3 –11 µm, in ZMA Por. 13446 it is 48– 84 –102 x 5 – 7.4 –9 µm.

Distribution and ecology. Saudi Arabian Red Sea, Israelian Gulf of Aqaba, on reefs.

Remarks. The molecular sequence of the Jeddah specimen grouped with Voigt et al. ’s C. rowi specimens (cf. Fig. 2A ); no sequence for the Aqaba specimen was obtained. For that reason we present separate morphological data for the two available specimens. The shape of the cormus of the Jeddah specimen with the longer wider tubuli combined with a fine network of thinner tubuli is the same as in Voigt et al. ’s type series. However, the shape (cylindroconical) and the size (up to 151 µm) of the triactines of the Jeddah specimen differ from the triactines of the type series, which has actines up to 103 µm long as described by Voigt et al. The Aqaba specimen has a comparable spicule size as the type series.

Sequence data for specimens assigned to C. rowi by Voigt et al. 2017 were not strongly separated from sequences we found in specimens which we assigned to Clathrina luteoculcitella Wörheide & Hooper, 1999 (cf. Fig. 2A ). A larger clade with high bootstrap value unites our specimen and Voigt et al. ’s (2017) specimens of C. rowi , with Indonesian and Australian specimens of C. luteoculcitella as well as with Rodrigues specimens assigned below to C. luteoculcitella . In a separate analysis, a trimmed alignment with length 395 sites of both species comprising Australian (downloaded from the Sponge Barcode Project), Indonesian, Red Sea and Oman specimens of C. luteoculcitella , together 8 sequences, and 10 Red Sea sequences of C. rowi (most donated by Oliver Voigt, but including one of ours, RMNH 10002), showed nine non-conserved sites. Four of these sites showed a neat separation between C. luteoculcitella and C. rowi , the other 5 sites showed single specimen differences or a mixed set of differences.

Figures

FIGURE 2. Maximum-likelihood tree based on analysis of sequences of the partial 28S gene (C2–D2 region, comprising 442 sites) of Western Indian Ocean Calcinea newly generated by the Naturalis Biodiversity Center and sequences additionally obtained from GenBank, the Sponge Barcode Project and from Oliver Voigt (München) from the Red Sea, Indonesia, Australia, and a few sequences from other parts of the world, to demonstrate the affiliation of the compared species. Please note that Arturia sequences do not appear in the same clade, indicating Arturia is non-monophyletic. Numbers at the root of clades are bootstrap values of 1000 replicates. Since the high number of sequences were difficult to read in detail, we subdivided the present tree in three detailed sections 2A, 2B, and 2C.

FIGURE 16. Clathrina rowi Voigt et al. 2017, RMNH Por. 10002, Saudi Red Sea, Jeddah, field nr. JED209, a, in situ on the reefs (photo N.J. de Voogd), b, light microscopic view of the cormus, c, SEM image of the spicules.

FIGURE 17. Clathrina rowi Voigt et al. 2017, ZMA Por. 13446, from Israel Red Sea, Aqaba, a, in situ in cave, b, light microscopic view of the cormus, c, SEM image of the spicules.