Timea curacaoensis, Van, Rob W. M., 2009

Van, Rob W. M., 2009, New sciophilous sponges from the Caribbean (Porifera: Demospongiae), Zootaxa 2107, pp. 1-40 : 12-13

Timea curacaoensis n. sp.

( Figs 4 A–E)

Holotype. ZMA Por. 16887, Netherlands Antilles, Curaçao, near Carmabi, 12.124°N - 68.975°W, in reef cavity at approx. 10 m, 10-2001, coll. S. Scheffers #35.

Description. Thinly encrusting, microlobate and microhispid; size of now fragmented holotype 15 x 3 x 1.5 mm. Live color not noted, off-white in alcohol.

Skeleton. Individual tylostyles are erect on the substrate, tyles down. Pointed ends protrude far beyond the surface. The tylostyles are partly hidden by a dense layer of asters.

Spicules. Tylostyles and two categories of asters, one of which has branching rays.

Tylostyles ( Figs 4 A–B) with elongate tyles, often style-like or with subterminal tyles, 299- 834.2 - 1357 x 2 - 8.2 -14 µm

Larger asters ( Figs 4 C–D), seemingly but not truly asymmetrical, with 4–5 rays which have 2 or 3 secondary branches, juvenile large asters have smooth rays, while adult asters have thicker rays, often with a few spines along the shaft, and they have proliferated terminal branches, overall diameter 14- 19.2 -23 µm.

Small tylasters ( Fig. 4 E) with 8–9 unbranched terminally spined rays, 5.5- 6.0 -7.5 µm in diameter.

Ecology. In reef cavities at approx. 10 m.

Etymology. Named after its type locality.

Remarks. Members of the genus are typical sciophilous specialists, invariably found in thin patches under stones or overhangs (e.g. Rützler, 2002b; Carballo & Cruz-Barraza, 2006). The North Atlantic and Mediterranean Timea species were recently listed by Lehnert & Heimler (2001). Along with some representatives of other genera ( Diplastrella and Adreus ), they list seven recognizably described species reported from the Caribbean region, T. parasitica ( Higgin, 1877) , T. stelligera ( Carter, 1882) , T. stenosclera Hechtel (1969) , T. mixta sensu Wiedenmayer (1977) , T. unistellata sensu Pulitzer-Finali (1986) , T. hechteli Lehnert & Heimler (2001) , and T.micraster Lehnert & Heimler (2001) . In view of the proximity it makes sense to include in a comparison of our new species also Brazilian respresentatives: Timea agnani Boury- Esnault (1973) and T. stellifasciata sensu Boury-Esnault (1973) , T. authia sensu de Laubenfels (1956), T. mixta sensu Hechtel (1976) and T. bioxyasterina Mothes et al. (2004) . Of these species, only Timea stellifasciata sensu Boury-Esnault (1973) bears some resemblance to our new species. Boury-Esnault records two types of asters, the larger of which has reduced number of rays with ‘multifide’ endings, size also similar to ours, 12–28 µm. These asters, called ‘sphaeranthasters’ by Boury-Esnault, do not have really branched rays. The second smaller category of asters are oxyasters, unlike the tylasters of our species. The Brazil material probably belongs to an undescribed species, as the Mediterranean Timea stellifasciata sensu Sarà & Siribelli (1960) appears to be distinct from the Brazil material, with irregular, but unbranched asters, showing no signs of having ‘multifide’ rays. T. hechteli , T. mixta , T. stenosclera and T. micraster possess two categories of asters one of which is a spheraster, which is not found in our new species, while T. stelligera and T. perastra have only one category of tiny asters, lacking the larger ones, whereas T. unistellata has a single category of larger spheroxyasters. T. stelligera may not be a true Timea as its type is described as a massive conical sponge, unlike any other Timea . T. authia sensu de Laubenfels (1956) is not described, but the use of the name of a species originally described from California is presumed to testify of morphological similarities between the Californian and Brazilian specimens. T. authia was extensively redescribed by Carballo & Cruz- Barraza (2006) and the asters are regular strongylasters quite different from the present new species. T. bioxyasterina has three categories of asters, one tylaster and two categories of oxyasters. T. agnani has a single category of very large four-rayed asters, and reexamination of the type material led Mothes et al. (2004) to conclude that this is probably a Cyamon ( Poecilosclerida , Raspailiidae ).

Elsewhere, several species seem close, notably Mediterranean T. fasciata Topsent (1934) , which has irregular asters with proliferated ray endings, next to smaller normal strongylasters. Mediterranean T. geministellata Pulitzer-Finali (1978) possesses similar ambiguous spicules but some of these assume a diplaster-shape. Mediterranean T. irregularis Sarà & Siribelli (1960) has irregular larger asters of which some shapes could be interpreted as having branching rays in addition to small regular asters. The same could perhaps be said for Mediterranean T. bifidostellata Pulitzer-Finali (1983) , but the drawings of the spicules do not look very much like those of the new species, possibly because the drawings are rather vague. No other Timea species appear to possess similar branched asters.

To facilitate recognition of Timea species in the area, a key is presented below.

Figures

FIGURE 4. Timea curacaoensis n. sp., SEM images of spicules (Holotype ZMA Por. 16887). A – B. Tylostyle and details of head and apex; C. Full grown, thick-rayed, branched euaster, each ray with 2 – 4 spined cladi; D. Thinner branched euaster, each ray showing 2 – 3 spined cladi; E. small tylaster.