Contributions to Zoology, 74 (3/4) 271-278 (2005) Shallow-water Niphatidae (Haplosclerina, Haplosclerida, Demospongiae) from the São Sebastião Channel and its environs (tropical southwestern At- lantic), with the description of a new species U. S. Pinheiro1, 2, *, R.G.S. Berlinck 3, **, E. Hajdu 2, *** 1Departamento de Ciências Biológicas, Universidade Estadual do Sudoeste da Bahia, Rua José Moreira So- brinho, s/n, 45200-000, Jequiezinho, Jequié, BA, Brazil; 2Departamento de Invertebrados, Museu Nacional, Universidade do Brasil, Quinta da Boa Vista, s/n, 20940-040, Rio de Janeiro, RJ, Brazil; 3Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, SP, Brazil; *FAPERJ fellow, e-mail: upinheiro@gmail. com; **CNPq fellow, e-mail: [email protected]; ***CNPq fellow, e-mail: [email protected] Key words: Porifera, Demospongiae, Haplosclerina, Niphatidae, tropical southwestern Atlantic, taxonomy, new species Abstract Comparison of the niphatids collected in the São Sebastião Channel area and its environs with data Two niphatids are described here: Amphimedon viridis and compiled from the literature lead us to identify Am- Pachychalina alcaloidifera sp. nov. Amphimedon viridis is a common and conspicuous species in most of the tropical western phimedon viridis and a new species, Pachychalina Atlantic. Pachychalina alcaloidifera sp. nov. has this far been alcaloidifera sp. nov., to be described below. found only in the coasts of Rio de Janeiro and São Paulo states. Both species are described on the basis of series of specimens observed alive. Material and methods Specimens were collected during a faunistic survey Contents conducted in the area of the São Sebastião Channel and its environs, in the municipalities of São Sebas- Introduction .................................................................................... 271 Material and methods ................................................................... 271 tião and Ilhabela, situated in the northern sector of Systematics ..................................................................................... 271 the São Paulo State coastline (Fig. 1). Additional Order Haplosclerida Topsent, 1928 ..................................... 271 collections were made at do Pai Island (off Praia de Amphimedon Duchassaing and Michelotti, 1864 ....... 272 Itaipu, Niteroi, central sector of Rio de Janeiro State Amphimedon viridis Duchassaing and Michelotti, 1864 .......................................................... 272 coastline). Pachychalina Schmidt, 1868 ......................................... 274 Sponges were collected by snorkeling or scuba Pachychalina alcaloidifera sp. nov. ....................... 274 diving, and photographed in situ whenever possible. Discussion ...................................................................................... 276 Preparations of dissociated spicules and thick-sec- Acknowledgements ...................................................................... 277 tions mounts follow the usual procedures described References ...................................................................................... 277 elsewhere for study under light microscopy (Mothes de Moares, 1985; Hooper, 1997). Introduction A qualitative survey of the sponge fauna of the São Systematics Sebastião Channel area and its environs has been conducted during the years of 1996 and 1997, reveal- Order Haplosclerida Topsent, 1928 ing over 140 species (Hajdu et al., 1996; Hajdu et al., Suborder Haplosclerina Topsent, 1928 1999). Ongoing collecting effort is centred on yielding Family Niphatidae Van Soest, 1980 additional specimens of rare species, registering pho- tographically intrapopulational variability in situ, and Diagnosis. “Haplosclerida with three-dimensional subsidizing biological natural products research. ectosomal skeleton of multispicular fi bres. Choano- Downloaded from Brill.com10/04/2021 12:17:09AM via free access 272 Pinheiro et al. – Shallow-water Niphatidae from São Sebastião Channel Fig. 1. Map showing the São Sebastião Channel area and its geographic position in relation to the eastern coast of South America. Localities where the specimens studied here were seen are indicated. n Pachychalina alcaloidifera sp. nov. l Amphimedon viridis Duchassaing and Michelotti, 1864 and 5 both species. somal skeleton of multispicular fi bres, cored by Amphimedom viridis Duchassaing and Michelotti, oxeas, often strongylote or stylote. Microscleres if 1864 present, sigmas or microxeas” (Desqueyroux-Faún- (Figs. 2a-c, Table 1) dez and Valentine, 2002). Material. MNRJ 415, between Praia Grande and Praia Preta (São Sebastião Channel, São Sebastião, SP, Brazil, 23o49.247’S Genus Amphimedon Duchassaing and Michelotti, 45o24.435’W), coll. A. Mota, 30-I-1995; MNRJ 428, Praia Grande 1864 (São Sebastião Channel, São Sebastião, SP, Brazil, 23o51.474’S 45o27.276’W), 6 m depth., coll. F.L. Silveira and A.C. Morandini; Diagnosis. “Niphatidae with an optically smooth MNRJ 1028, São Sebastião, SP, Brazil, coll. R.G.S. Berlinck; surface, regular tangential ectosomal network with MNRJ 1030, 1031, between Praia Grande and Praia Preta (São Sebastião Channel, São Sebastião, SP, Brazil, 23o49.247’S rounded meshes of a single size. Ends of choano- 45o24.435’W), coll. A.C. da Motta, 30-I-1995; MNRJ 1032, somal longitudinal primary fi bres barely protruding. Praia Preta (São Sebastião Channel, São Sebastião, SP, Brazil, Spongin abundant. Microscleres absent.” (Desquey- 23o49.247’S 45o24.435’W), coll. R.G.S. Berlinck; MNRJ 1699, roux-Faúndez and Valentine, 2002) Pedra Montada, Praia de Barequeçaba (São Sebastião Channel, São Sebastião, SP, Brazil, 23o49.746’S 45o26.478’W), 2.5 m depth, coll. E. Hajdu, 29-IV-1997; MNRJ 1973, Praia das Con- Type species. Amphimedon compressa Duchassaing chas, Picinguaba (Ubatuba, SP, Brazil), 1-2 m depth, coll. U.S. and Michelotti, 1864. Pinheiro and S. Ribeiro, 09-XII-1998; MNRJ 2016, Pedra Downloaded from Brill.com10/04/2021 12:17:09AM via free access Contributions to Zoology, 74 (3/4) – 2005 273 Montada, Barequeçaba (São Sebastião, SP, Brazil, 23o49.746 at São Sebastião it accounted for 2.31% of total 45o26478), coll. R.G.S. Berlinck, 06-II-1999, Biota/Fapesp, sponge coverage, being the 8th more abundant spe- Bentos Marinho Project; MNRJ 7170, dos Porcos Pequenos cies (Hajdu et al., unpubl. res.). Island (Ubatuba, SP, Brazil); MNRJ 7171, 7552, The Islands, off Praia da Baleia (São Sebastião, SP, Brazil); MNRJ 7550, Ilha Massaguaçu (Caraguatatuba, SP, Brazil); MNRJ 7557, Remarks. Several specimens were seen in the fi eld Picinguaba (Ubatuba, SP, Brazil); MNRJ 8519, Ubatuba (SP, through a quantitative assessment of sponge abun- Brazil); MNRJ 8521, Caraguatatuba (SP, Brazil). dance conducted at São Sebastião (Hajdu et al., un- publ. res.). It appears that digitiform projections are Amphimendon viridis. Brazilian records: Muricy, not associated to the dimensions of the specimens, 1989: 351; Muricy et al., 1991: 1186; Muricy et al. but to habitat pressures such as the need to outgrow 1993: 429; Berlinck et al. 1996; Hajdu et al. 1999; competing neighbouring organisms (e.g. specimens Muricy and Ribeiro, 1999: 85. growing in between zoanthid polyps of the genera Further synonymy: see Wiedenmayer, 1977: 84. Palythoa and Zoanthus). The largest collected speci- men (MNRJ 1699) had not a single projection. There Description of specimens collected on the São Paulo is a green Halichondria occurring in the São Se- State coast. Massive cushion-like or lobate, only bastião Channel area and environs, viz. H. cebima- rarely repent. Live colour, several shades of green, rensis Carvalho and Hajdu, 2001 which could inad- mostly mat/dull, several shades of brown in spirit. vertently be mistaken for A. viridis. In situ distin- Surface hispid and rough, reticulated to the naked guishing characters are the sligthly lighter (sometimes eye. Oscules spread at random, fl ush or on top of turquoise) shade of green, the smoother and easily projections. Area coverage was as large as 225 cm2, peeled off surface (neatly reticulated) and the tough- with ca. 30 cm2 as a mean value. Ectosomal skeleton er consistency in the Halichondria. Brazilian Am- a tangential reticulation where multispicular tracts phimedon viridis have recently been thoroughly form circles 200-450 μm in diameter. Choanosomal described by Muricy and Ribeiro (1999) where fur- skeletal architecture a regular reticulation with pri- ther comparative data is to be sought. mary multispicular ascending tracts interconnected by irregular secondary fi bres. Abundant spongin Genus Pachychalina Schmidt, 1868 cementing fi bres, and many free spicules. Spicules Defi nition. “Niphatidae with a paratangential ectos- (Table 1) are oxeas, robust, slightly curved and taper- omal reticulation of fi bres or tracts obscured by an ing not so gradually, 146-210 μm long and 5-14 μm irregularly, conulose to spiny surface, pierced by thick. abundant aquiferous orifi ces. Choanosomal tracts Table 1. Micrometric data for the oxeas of selected specimens of have no sheath of spongin.” (Desqueyroux-Faúndez Amphimedon viridis Duchassaing and Michelotti, 1864 (in μm, and Valentine, 2002) N=20). Type species. Pachychalina rustica Schmidt, 1868. Specimen Spicules (length/width) smallest – mean – largest Remarks. Pachychalina as used here is considered MNRJ 428 149 – 164 – 180 / 10 – 11.6 – 14 MNRJ 1028 151 – 176 – 210 / 15 – 10.3 – 14 distinct from closely allied genera by its lack of a MNRJ 1030 158 – 171 – 194 / 16 – 10.0 – 12 clear