Timea clippertoni, Van, Rob W. M., Kaiser, Kirstie L. & Syoc, Robert Van, 2011

Van, Rob W. M., Kaiser, Kirstie L. & Syoc, Robert Van, 2011, Sponges from Clipperton Island, East Pacific, Zootaxa 2839, pp. 1-46 : 11-12

Timea clippertoni n. sp.

( Figs 5 A–E)

Holotype. MNHN DCL 4044–A, Jean-Louis Etienne Expédition Clipperton 2005, station 18, 55 m, on dead corals, 20–01–2005, 1 specimen.

Description. Thinly encrusting on the underside of dead corals, less than 1 mm in thickness, forming microhispid patches of a few mm2. No apparent oscules. Pale beige in alcohol.

Skeleton. Tight mass of small tylostyles and asters pierced by the shafts of long tylostyles. Tylostyles with heads on the substrate, pointed ends directed outwards. Large asters form a basal layer on the substrate.

Spicules. Tylostyles, euasters in three distinct categories ( Fig. 5 B).

Tylostyles ( Fig. 5 A) with prominent, often slightly subterminal heads, usually slightly to strongly curved, in a large size range, possibly divisible in long tylostyles few in number and numerous small tylostyles, but some intermediates occur, 119– 366.0 –963 x 2 – 4.6 –9 µm, heads 3– 6.8 –11 µm.

Asters 1 ( Fig. 5 C), calthrops-like, with usually 4 rays, but occasionally 3 or 5–6 heavily spined conical rays ending in a sharp point, large size variation, diameter 21– 42.2 –78 µm, individual rays 15– 28.5 – 51 x 4 – 6.8 –9 µm.

Asters 2 ( Fig. 5 D), strongylospherasters with large center, appox. 8–16 heavily spined conical rays, 9– 15.7 –19 µm.

Asters 3 ( Fig. 5 E), oxyspherasters with large center, small size, approx. 8–12 smooth or lightly spined rays, diameter 5– 7.1 –9 µm.

Etymology. Named after the discoverer of the Island, John Clipperton, who sighted the island in 1705.

Ecology. Encrusting dead corals, deep reef environment (55 m).

Remarks. The large heavily spined calthrops-like asters are reported from six Timea species (see Table 2 ). (1) Timea tetractis Hentschel, 1912 from Indonesia, is similar to our material, but the upper size of the calthropslike asters (called chelotrope-like aster by Hentschel) is given as 15–31 µm, clearly considerably less than those of T. clippertoni n. sp. Also the tylostyles are smaller (up to 520 µm). Strongylasters are present of up to 12 µm only.

(2) Timea stellifasciata Sarà & Siribelli, 1960 from the Mediterranean differs from our new species in the smaller megasclere size (125 – 595 µm) and the smaller calthrops-like asters (up to 21 µm) The asters are regarded to have a continuous variation from very small regular oxyspherasters to large irregular branched and spined types, whereas our material has distinct categories of smaller regular asters and larger calthrops-like asters. Timea stellifasciata also has the latter with branched rays, which is not found in our material.

(3) The species Timea stellifasciata was also reported from Brazil ( Boury-Esnault 1973), but this likely concerns an undescribed species. The large spined calthrops-like asters of this material are much smaller than those of our new species. Boury-Esnault (1973) also described Timea agnani with large four-rayed microscleres; however, this is in all probability a species of Cyamon .

(4) Timea irregularis Sarà & Siribelli, 1960 , also from the Mediterranean, is more similar to our new species with megascleres in the same size range (252–1025 µm), distinct categories of small regular oxyspherasters, and a larger upper size range of the calthrops-like asters (up to 35 µm), though still quite a bit smaller than the upper size in our new species. The shape of the calthrops-like asters in T. irregularis is clearly much more irregular than those of our material and constitutes a distinct difference.

(5) Timea cumana Pulitzer-Finali, 1978 from the Mediterranean has the calthrops-like asters similar in shape as those of T. clippertoni n. sp., but smaller in size (up to 27 µm), whereas the tylostyles reach a length of 1600 µm, clearly in excess of those of our material. A second smaller category of strongylasters appears similar.

(6) Timea curacaoensis Van Soest, 2009 was recently described from coral reef rubble off the coast of Curaçao. The aster complement is likewise consisting of normal shaped smaller asters and larger asters with irregular shape, which is caused by proliferation / branching of the rays, quite unlike the asters of our new species. The size of the latter is also clearly smaller.

Timea aff . stelli- not recorded 160–730 x 12–28 (ray 16–30 6–9 NE Brazil

fasciata sensu 3–6 length, so prob-

Boury-Esnault, ably at least up

1973 to 40)

Timea curacaoen- off-white 299– 1357 x 14–23 5.5–7.5 not recorded Curacao, Carib-

sis Van S o es t, (alcohol) 2–14 bean

2009

Other, more ‘normal’ Timea species from the Indo-West Pacific are: Timea ohuirae Carballo & Cruz-Barraza, 2006 from the Pacific coast of Mexico is similar to our new species in the sizes of the tylostyles and the diversity of asters. Like our new species it has three categories of asters, approximately in the same size range, but the largest category is a commonplace oxyaster with spined rays, not calthrops–like and proliferated; the smallest category is a strongylaster, not an oxyaster like our new species. Timea granulata Bergquist, 1965 from Palau also has a diversity of asters, including some with a reduced number of rays, but sizes are much smaller than those of our new species. Timea species from Hawaii reported by De Laubenfels (1954b), T. xena and T. tethya (as Kotimea ) differ from the new species in lacking the large proliferated asters.

Timea lophastraea ( Hentschel, 1909 as Hymedesmia ) has peculiar ‘lophasters’ consisting of four or six rays with proliferated apices, different from the calthrops-like asters of our new species. Also this sponge apparently possesses bouquets of small oxeas at the surface, which make it likely that is a member of Hemiasterellidae , not Timeidae . Timea centrifera ( Hentschel, 1909 as Hymedesmia stellata var. centrifera ) is a proper Timea with commonplace strongylasters of 10–18 µm diameter. Both species are from West Australia.

Figures

FIGURE 5. Timea clippertoni n. sp., spicules from holotype MNHN DCL 4044 – A, A. tylostyle, B. overview of spiculation to demonstrate relative sizes, C. larger and smaller calthrops-like asters, D. strongylospheraster, E. oxyspheraster.

Tables

TABLE 2. Timea species with modified, irregular or calthrops-like asters.

Name	Color	Tylostyles (µm)	Modified asters Strongylospher- (diameter µm) asters (diameter µm)	Oxyspherasters (diameter µm)	Locality
Timea clippertoni n. sp.	beige (alco- hol)	119–963 x 2–9	21–78 9–19	5–9	ÎleClipperton
Timea tetractis Hentschel, 1912	bright grey (alcohol)	184–520 x 2–7	15–31 7–12	7–12	Aru Islands, Indonesia