Timea bioxyasterina, Mothes & Santos & De Campos, 2004

Mothes, Beatriz, Santos, Cristina P. & De Campos, Maurício A., 2004, Timea bioxyasterina sp. n., a new species from the Northeastern coast of Brazil (Demospongiae, Hadromerida), Zootaxa 443 (1), pp. 1-8 : 1-8

Timea bioxyasterina sp. nov.

( Figs. 2–3 )

Holotype. MNRJ 7984 , off coast Maranhão State, 01°51’00”S – 43°48’00”W, 35.5 m depth, coll. Fishing boat ‘IV SUDENE’, 25/ii/1973. Sand substratum.

Schizoholotype­slides. MCNPOR 1850.

Comparative material. Timea sp. aff. unistellata (Topsent, 1892) —ZMAPOR 9198, Bonaire, West Indies (fragment deposited in MCNPOR 2644).

Diagnosis. Timea bioxyasterina sp.n. is set apart from the other Atlantic species by its two categories of oxyasters: one bigger with smooth rays and the other shorter with microspined rays.

Description. The specimen is a 1 cm thick encrustation, approximately 10 cm 2 in surface area ( Fig. 2a ), fixed on a stone fragment. Surface smooth. No orifices observed. Consistency not compressible. Light­brown colored in ethanol.

Skeleton. The ectosome and the choanosome were not observed, because it’s a very thin fragment. Euasters in a random distribution, all over the sponge body. Ascending multispicular tracts of tylostyles occur, isolated and protruding through the surface ( Fig. 2b ).

Spicules. Tylostyle ­ ( Fig. 3a ). Straight, some slightly curved shafts in the terminal half, blunt end; 304­ 579.5 ­ 769.5 m X 6.3­ 10.5 ­ 15 m (N=25). The heads are spherical to ovoid, some bilobed; diameter 2.5­ 12.3 ­ 17.5 m (N=25). Oxyaster I ­ 9 to 11 conical, smooth, straight rays, rare bifurcated, some slightly curved specially in the terminal half ( Figs. 3a, 3b ); 32­ 62 ­ 85.8 m diameter. Oxyaster II ­ 9 to 11, conical, microspined rays, mostly in the apical half ( Figs. 3b, 3c, 3d ); 16.1­ 20.7 ­ 27.6 m in total diameter. Tylaster ­ 9 to 10 cylindrical rays with swollen extremities, microspined along the axis ( Figs. 3c, 3d ); 2.4­ 3.6 ­ 5 m in total diameter.

TABLE I: Brazilian species of Timea .

Etymology. The species name refers to the presence of two categories of oxyasters.

Remarks. Four other species of Timea have been reported from the Brazilian coast (Table I). Timea authia De Laubenfels, 1930 , originally recorded from California ( U.S.A.) was subsequently cited by De Laubenfels (1956) for Ubatuba (São Paulo State, Brazil). It differs from the new species in having smooth to rugose tylasters, and a mix of tylostyles and styles, contrary to the new species' two categories of oxyasters and megascleres, which are always tylostyles. Timea stellifasciata Sarà & Siribelli, 1960 , first described from the Gulf of Naples ( Italy), was later identified by Boury­Esnault (1973; MNHN­ LBIM­NBE 959 examined) for the coast of the State of Alagoas ( Brazil). It is distinguished from the new species through its microspined oxyasters associated to sphaeranthasters, a caltrop­like asters, and megascleres, which range from tylostyles, to subtylostyles or styles. Timea agnani Boury­Esnault, 1973 is best assigned to Cyamon vickersii (Bowerbank, 1864) ( Raspailiidae ; UFRJPOR 3381, fragment from the holotype examined). Timea mixta ( Topsent, 1896) , described from the Mediterranean firstly (Holotype reexamined MNHN­LBIM­DT 2449), was reported by Hechtel (1976) from Recife (Pernambuco State, Brazil), and differs in having oxyasters next to strongylasters.

Comparison with known Caribbean species— Timea perastra (De Laubenfels, 1936) , Timea stellata (Bowerbank, 1866) , Timea stelligera (Carter, 1882) , Timea stenosclera Hechtel, 1969 and Timea unistellata (Topsent, 1892) differs by the presence of only one kind of microscleres. Timea parasitica (Higgin, 1877) and Timea hechteli Lehnert & Heimler, 2001 differ in having spherasters. Timea micraster Lehnert & Heimler, 2001 (Lehnert, pers. comm.) is best assigned to Diplastrella (Spirastrellidae) . The new species approaches T. mixta ( sensu Wiedenmayer, 1977 ), which also possesses oxyasters, although in a single size category. Further distinction stems from the latter’s possession of strongylasters in addition.

Figures

FIGURE 2. Timea bioxyasterina sp. nov. (Holotype, MNRJ 7984). a. Specimen fixed and preserved in alcohol (Scale bar = 1 mm); b. Skeletal arrangement (Scale bar = 200 µm).

FIGURE 3. Timea bioxyasterina sp. nov. (Holotype, MNRJ 7984). Spicules: a. Tylostyles and oxyasters I, II (Scale bar = 10mm); b. Oxyasters I and II (Scale bar = 10mm); c. Oxyaster II and tylaster (in detail; Scale bar = 5mm). d. Tylasters (in detail; Scale bar = 1mm).