Podospongia colini, Sim-Smith, Carina & Kelly, Michelle, 2011

Sim-Smith, Carina & Kelly, Michelle, 2011, Two new genera in the family Podospongiidae (Demospongiae: Poecilosclerida) with eight new Western Pacific species, Zootaxa 2976, pp. 32-54 : 39-40

Podospongia colini sp. nov.

( Fig. 1 B, 2B, 3E–I)

Podospongia sp. Colin & Arneson (1995: 20).

Material examined. Holotype ― USNM 1154618: Cape Tarabitan (Torowitan), northern tip of Sulawesi, Indonesia, 1.752° N, 124.981° E, 50 m, collected on SCUBA by Dr Patrick L. Colin, CRRF, 21 May 1993; schizotypes are held at NIC, NIWA, Wellington, as NIWA 62047. Paratype ― USNM 1154619: Cape Tarabitan (Torowitan), northern tip of Sulawesi, Indonesia, 1.752° N, 124.981° E, 50–67 m, collected on SCUBA by Dr Patrick L. Colin, CRRF, 21 May 1993.

Type location. Cape Tarabitan, North Sulawesi, Indonesia.

Distribution. Known only from type location.

Description. Stipitate sponge, 90 mm high (holotype), with an elliptical body 15 mm wide, on a flexible stalk 4–5 mm diameter, attached to the substrate by a solid expanded base ( Fig. 1 B). Paratype has a total length of 86 mm, body is 16 mm high and 9.5 mm wide. One or two raised oscules are present on the apex of the body in life, occasionally on one side of the sponge. Ostia are visible under magnification and scattered in the ectosomal membrane. Surface inflated and undulating in life, granular to the touch, texture compressible, stalk tough. Colour in life peach orange and in ethanol cream throughout.

Skeleton. Ectosome a moderately dense layer of microscleres surrounding the body and stalk, through which emerge brushes of small slender strongyloxeas. The stalk consists of short thick anisostrongyles forming a dense spongin-encased reticulation, with long thin strongyloxeas forming irregular brushes that emerge in the ectosome through a crust of microscleres. The dense spongin reticulation of the stalk gives way to multiple dendritic tracts of strongyloxeas that spray in an umbelliform arrangement within the globular body, expanding to form brushes at the surface. Microscleres are scattered through the choanosome ( Fig. 2 B).

Megascleres ( Fig. 3 E–F, Table 1)― Anisostrongyles ( Fig. 3 E), thick, irregularly curved with strongylote ends, forming the spongin-encased reticulation within the stalk; 391 (350–500) x 16 (10–20) μm. Strongyloxeas I ( Fig. 3 F), long, thin, faintly polytylote, with a very fine needle-like distal end, forming the secondary tracts that emerge through the globular body; 821 (700–930) x 8 (6–10) μm. Strongyloxeas II, shorter, thin, also faintly polytylote, forming the brushes of the ectosome in the stalk and body; 591 (530–710) x 8 (6–10) μm.

Microscleres ( Fig. 3 G–I, Table 1)― Aciculospinorhabds, regularly spined, asymmetrical. Basal whorl composed of a regular tight cluster of spines. Apical whorl and apex merge into a cluster of spines, more densely clustered than the basal whorl; 28 (25–30) μm long x 18 μm wide. Protospinorhabds sigmoid ( Fig. 3 I), around 10 μm in length, older protospinorhabds ( Fig. 3 H) have numerous projections.

Substrate, depth range, and ecology. The sponge was collected from a fringing reef wall between 50–67 m where it was reasonably common.

Etymology. Named after Dr Patrick L. Colin, Director of the Coral Reef Research Foundation, Palau, in recognition for the enormous contribution he has made to our knowledge of Indo-Pacific sponge biodiversity, through his extensive SCUBA and manned-submersible collections over the last 20 years. Dr Colin has a penchant for deep-diving, and the collection of obscure and unusual deep-water creatures.

Remarks. Podospongia colini sp. nov. was first recorded as an undescribed species, and figured in Colin & Arneson (1995, p. 20). P. colini sp. nov. is the largest Podospongia species recorded at 90 mm total length, although New Caledonian P. similis ranges from 57–80 mm ( Lévi 1993) and P. virga sp. nov., from northern New Zealand, has a total length of 70 mm. Unlike P. similis , P. colini sp. nov. (and P. virga sp. nov.) has a simple aquiferous system where surface ostia lead to several single and multiple oscules on the lateral and apical faces of the sponge. P. colini sp. nov. is found in shallow tropical reef habitat (50–67 m), similar to the habitat of P. natalensis (Table 1). All other species of Podospongia are considered to be deep-water species.

Like P. virga sp. nov., P. colini sp. nov. has a category of smaller anisostrongyles in the stalk region, but unlike P. virga sp. nov. and P. similis , it has two further categories of strongyloxeas instead of anisoxeas. The smaller strongyloxeas project beyond the surface of the sponge giving it a slightly hispid texture. P. colini sp. nov. has the smallest aciculospinorhabds of the three species; they are less regular than those of P. virga sp. nov. and P. similis . With their irregular multifurcate projections they superficially resemble the spinorhabds of Negombata magnifica , figured in Kelly-Borges & Vacelet (1995, Fig. 3 k).

P. colini sp. nov. has the same form of aciculospinorhabds as P. similis and P. virga sp. nov., where the apex is a tuft of short bifurcate or trifurcate spines that may or may not project beyond the general apex. These differ markedly from species in the Atlantic Ocean which have aciculospinorhabds with elongate individual spines that project well beyond the apical whorl and basal whorl in some cases.

Figures

FIGURE 1. New genera and species of Podospongiidae from New Zealand, Australian, and Indonesian waters: A. Podospongia virga, holotype NIWA 52692, Cape Reinga, New Zealand; B. Podospongia colini, holotype USNM 1154618, Sulawesi, Indonesia; C. Neopodospongia pagei, holotype NIWA 52580, Three Kings Islands, New Zealand; D. Neopodospongia exilis, holotype NIWA 52579, Cavalli seamounts, New Zealand; E. Neopodospongia bergquistae, holotype NIWA 62016, Poor Knights Islands, New Zealand; F. Diplopodospongia teliformis, holotype NIWA 35005, Hikurangi Channel, New Zealand; G. Diplopodospongia rara, holotype NIWA 52693, Campbell Plateau, New Zealand; H. Diplopodospongia macquariensis, holotype QM G 331915, Seamount 8, Macquarie Ridge, Australia. Scale = 10 mm for all images.

FIGURE 2. Generalised skeletal architecture of new Podospongiidae genera and species: A. Podospongia virga, with secondary tract formation evident within the globular part of the body; B. Podospongia colini, with dendritic non-divergent tracts within the globular part of the body; C. generalised skeletal architecture of Neopodospongia species; D. generalised skeletal architecture of Diplopodospongia species.

FIGURE 3. Megascleres and microscleres of Podospongia spp. nov.: Podospongia virga, holotype NIWA 52692, A. anisostrongyle of stalk; B. anisoxea, scale A & B = 100 µm; C. spinorhabd; D. immature spinorhabd, scale C & D = 20 µm. Podospongia colini, holotype USNM 1154618, E. anisostrongyle of stalk; F. anisoxea, scale E & F = 100 µm; G. spinorhabd, H. immature spinorhabd; I. immature sigmoidal spinorhabd, scale G – H = 20 µm.