Suberites crispolobatus, Van, Rob W. M., 2017

Van, Rob W. M., 2017, Sponges of the Guyana Shelf, Zootaxa 1, pp. 1-225 : 190-192

Suberites crispolobatus sp. nov.

Figures 120 a–c

Material examined. Holotype RMNH Por. 9863, Suriname, ‘ Snellius O.C.P.S. ’ Guyana Shelf Expedition, station F40, 7.0033°N 56.4417°W, depth 59 m, bottom sand, 6 May 1966 .

Paratypes RMNH Por. 9738, Guyana, ‘Luymes’ Guyana Shelf Expedition, station 103, 7.9°N 57.5167°W, depth 85 m, triangular dredge, 4 September 1970 (1 specimen) ; RMNH Por. 9775, Suriname, ‘ Luymes O.C.P.S. II’ Guyana Shelf Expedition, station I115, 7.21°N 54.8617°W, depth 81 m, triangular dredge, 24 April 1969 (1 specimen) ; RMNH Por. 9814, Guyana, ‘Luymes’ Guyana Shelf Expedition, station 68, 7.4167°N 57.1333°W, depth 51 m, muddy sand bottom, 31 August 1970 ; RMNH Por. 9840, Guyana, ‘Luymes’ Guyana Shelf Expedition, station 85, 7.65°N 57.25°W, depth 69 m, bottom sand and shells, 2 September 1970 (1 specimen) ; RMNH Por. 9879, 9964, Suriname, ‘ Snellius O.C.P.S. ’ Guyana Shelf Expedition, station G56, 7.26°N 56.6667°W, depth 67–68 m, Agassiz trawl, 10 May 1966 (4 specimens) ; RMNH Por. 9891, Guyana, ‘ Snellius O.C.P.S. ’ Guyana Shelf Expedition, station H58, 7.4233°N 56.9067°W, depth 66–69 m, bottom coarse sand, 11 May 1966 (1 specimen) ; RMNH Por. 9899, 9960, 9985, 10503, 10548, Suriname, ‘ Snellius O.C.P.S. ’ Guyana Shelf Expedition, station F40, 7.0033°N 56.4417°W, depth 59 m, bottom sand, 6 May 1966 (23 specimens) ; RMNH Por. 9932, Guyana, ‘Luymes’ Guyana Shelf Expedition, station 63, 7.5833°N 57.0667°W, depth 71 m, sandy bottom, 31 August 1970 (1 specimen) .

Description. Erect rounded branches, often with club-shaped endings, and with small side lobes along their length; branches usually divided, but only a few times. The holotype RMNH Por. 9863 consists of a curled branch ( Fig. 120 a), similar to other such branches of e.g. paratype RMNH Por. 10548 ( Fig. 120 a1), but there are also wedge-shaped lobes, e.g. paratypes RMNH Por. 9985 ( Fig. 120 a2). Surface smooth but with irregular folds (possibly deflated as an after-collection artifact, as is often the case in larger Suberites species. There does not seem to be a massive basal body, individual branches have a pointed or thinner stalk-like basis. Sizes quite variable, up to 25 cm long, up to 1–3 cm in diameter. No apparent oscules but these are likely contracted. Color beige in alcohol. Consistency firm.

Skeleton. Typically Suberites -like, with bouquets of smaller tylostyles at the surface and more or less confused choanosomal skeleton. The center of the longer branches is more organized with tylostyles aligned lengthwise.

Spicules. ( Figs 120 b–c) Tylostyles only.

Tylostyles with prominent rounded heads, without obvious lobes except for thin growth stages which may have tuberculate heads; very variable in size, divisible into two size classes with some overlap, (1) larger ( Figs 120 b,b1), 456– 724 –858 x 9 – 11.4 –14 µm, and (2) smaller ( Figs 120 c,c1), 186– 266 –396 x 3 – 5.9 –10 µm.

Distribution and ecology. Guyana Shelf, muddy sandy bottom at 51–85 m depth.

Etymology. Crispus (L.) = curly, lobatus (L.) = having lobes, referring to the curled branches with lobes found in this species, at least in the preserved specimens.

Remarks. At first I assumed these specimens could be excessively ramose Suberites aurantiacus (Duchassaing & Michelotti, 1864) (p. 99, as Terpios ) or a similar species, like Suberites lobatus ( Wilson, 1902) (p. 399, as Phakellia lobata , slides of the holotype USNM 7684 examined), because spicule sizes are more or less the same of these two species. However, Dr Klaus Rützler (in litteris) convinced me that these have a massive base, and do not form such excessive long branches (see also Rützler & Smith 1993). Possibly, some deeper water records of these two species may conform to the present new species.

Figures

FIGURE 120. Suberites crispolobatus sp. nov., a, habitus of holotype RMNH Por. 9863 (scale bar = 1 cm), a 1, habitus of paratypes RMNH Por. 10548, a 2, habitus of two wedge-shaped paratypes RMNH Por. 9985 (scale bar = 1 cm), b – c, SEM images of the spicules, b, large tylostyle, b 1, details of b, c, small tylostyle, c 1, details of c.