Grantia aff. indica Dendy, 1913

Van, Rob W. M. & De, Nicole J., 2018, Calcareous sponges of the Western Indian Ocean and Red Sea, Zootaxa 4426 (1), pp. 1-160: 89-92

publication ID

https://doi.org/10.11646/zootaxa.4426.1.1

publication LSID

lsid:zoobank.org:pub:18929E20-5296-4458-8A8A-4F5316A290FD

persistent identifier

http://treatment.plazi.org/id/386CC616-DC2A-A56A-FF67-8D74FABDFC51

treatment provided by

Plazi

scientific name

Grantia aff. indica Dendy, 1913
status

 

Grantia aff. indica Dendy, 1913 

Figs. 52a–e View Figure , 53a–f View Figure

? Grantia indica Dendy, 1913: 20  , pl. 2 fig. 3, pl. 4 figs 4–5.

Material examined. ZMAAbout ZMA Por. 10223b, Seychelles, Mahé, NE coast, Cap Maçons and Anse de Forbans, 4.7667°S 55.5167°E, depth 0–6 m, snorkeling, coll. R.W.M. van Soest, field nr. NIOP-E stat. 612, 12 December 1992; ZMAAbout ZMA Por. 11566b, Seychelles, Amirantes, Île Desnoeufs platform, outer slope, 6.2167°S 53.0167°E, depth 12–15 m, scuba, coll. R.W.M. van Soest, field nr. NIOP-E stat. 738/22, 2 January 1993; ZMAAbout ZMA Por. 11749, Seychelles, Amirantes, Île Desnoeufs platform, outer slope, 6.2167°S 53.0167°E, depth 12–15 m, scuba, coll. R.W.M. van Soest, field nr. NIOP-E stat. 738/24, 2 January 1993.

Description. Small white, very ‘hairy’, sycon-like individuals ( Fig. 52a View Figure ). Largest specimen squat, 5 mm high, 4 mm in diameter, but smaller specimens ( Figs. 52b–c View Figure ) may be more elongate. Fringe of long diactines ( Figs 52b, d View Figure ) about 1 mm long.

Aquiferous system. Syconoid.

Skeleton. ( Figs 52d–e View Figure ) Skeleton articulate, with long diactines protruding obliquely from the surface, cortical skeleton a layer of larger and smaller sagittal triactines, tubar skeleton consists of rows of triactines. Subatrial skeleton of sagittal tetractines, atrial skeleton of tetractines with long apical actines, protruding into the atrial lumen ( Fig. 52e View Figure ). Fringe consists of long diactines supported by sagittal tetractines ( Fig. 52d View Figure ).

Spicules. ( Figs. 53a–f View Figure ) Diactines, trichoxeas, sagittal triactines, and sagittal tetractines.

Diactines of the main body ( Fig. 53a View Figure ), inequiended, blunt at the proximal end, sharp at the distal end, quite variable in length both in the same specimen and among specimens, 276– 641 – 1022 x 10 – 19.4 –24 µm.

Trichoxeas ( Fig. 53b View Figure ) of the fringe, inequiended with one end slight swollen and the other sharply pointed, often broken, length of the larger fragments 420–970–2000 µm, thickness 1.5– 4.1 –8 µm.

Cortical triactines ( Fig. 53c View Figure ), sagittal with oxhorn-shaped paired actines; unpaired actines 33– 108 –165 x 4 – 6.7 –12 µm, paired actines 66– 80 – 99 x 4 – 5.9 –7 µm.

Tubar triactines ( Figs 53d View Figure ), sagittal, with straight or slightly curved paired actines, occasionally T-shaped; length of unpaired actines 45– 73 –120 x 6 – 9.4 –13 µm, paired actines 66– 102 –156 x 7 – 9.7 –12 µm; these also occur in a low number in the fringe.

Subatrial and fringe tetractines ( Figs 53e View Figure ), unpaired actine usually longer than paired actine, with short apical actine; unpaired actines 78– 114 –156 x 7 – 8.4 –11 µm, paired actines 48– 90.0 –104 x 7 – 7.7 –9 µm, apical actines 14– 23 – 39 x 3 – 4.7 –7 µm. They occur also in the fringe.

Atrial tetractines ( Figs 53f View Figure ), with straight unpaired actines, almost straight paired actines and long slightly curved apical actines; unpaired actines 105– 139 –174 x 8 – 8.3 –10 µm, paired actines 90– 132 –171 x 6 –7.2–8 µm, apical actines 54– 128 –210 x 5 –7.8–9 µm.

Distribution and ecology. Seychelles, shallow reef down to 15 m.

Remarks. The present material shares the shape and the composition of the spicule package with Dendy’s (1913) type, but almost all spicules are smaller and thinner. Dendy is known to frequently cite only the largest measurements for a spicule category. The type was larger (10 x 4.8 mm) than our specimens and that may be an additional cause of the spicule size differences, but it is also possible that our material belongs to a closely related separate species, hence our ‘aff.’ designation. For the time being we emphasize the shared characters.

Unfortunately, our attempt to obtain 28S rRNA sequences failed.

Sycon tabulatum ( Schuffner, 1877)  (originally as Sycandra  ) has similar shape, but the radial tubes are crowned by a conus of small diactines and there are no giant diactines. The original combination is preoccupied by Sycandra tabulata Hackel, 1872  . Below (section ‘Additional species..’), a new name for Schuffner’s species is proposed.

ZMA

Universiteit van Amsterdam, Zoologisch Museum

Kingdom

Animalia

Phylum

Porifera

Class

Calcarea

Order

Leucosolenida

Family

Grantiidae

Genus

Grantia

Loc

Grantia aff. indica Dendy, 1913

Van, Rob W. M. & De, Nicole J. 2018

2018
Loc

Grantia indica

Dendy 1913: 20

1913
Loc

Sycon tabulatum (

Schuffner 1877

1877
Loc

Sycandra

Haeckel 1872

1872
Loc

Sycandra tabulata Hackel, 1872

Haeckel 1872

1872