Aplysina caissara Pinheiro & Hajdu, 2001

Pinheiro, Ulisses Dos S., Hajdu, Eduardo & Custódio, Márcio R., 2007, Aplysina Nardo (Porifera, Verongida, Aplysinidae) from the Brazilian coast with description of eight new species, Zootaxa 1609, pp. 1-51 : 3-7

Aplysina caissara Pinheiro & Hajdu, 2001 ( Figs. 1A , 2 , 3 A, Tab. I)

Aplysina caissara, Pinheiro & Hajdu (2001: 145) ; Mothes et al. (2006: 76). Aplysina fistularis fulva sensu Mothes de Moraes (1987: 133). Non Aplysina fistularis (Pallas, 1766; a valid species). Aplysina fulva sensu Lerner (1996: 115) . Non Aplysina fulva (Pallas, 1766; a valid species).

Holotype: MNRJ 1988, rocky coast between Prainha beach and Brava beach (Costão do Navio, São Sebastião, SP, 23º50.067' S- 45º29.449' W), 6 m depth, E. Hajdu coll., 29/I/1999.

Paratypes: MNRJ 268, Ponta Recife, (São Sebastião, SP, 23º49.501' S - 45º24.796' W), 2 m depth, E. Hajdu coll., 22/I/1996. MNRJ 578, southern side of Toque-Toque Island, (São Sebastião, SP, 23º51.209' S - 45º31.600' W), 11 m depth, E. Hajdu coll., 15/VI/1997. MNRJ 1673, Ponta do Jarobá (São Sebastião, SP, 23º49.679' S - 45º25.278' W), 4.5 m depth, E. Hajdu coll., 22/IV/1998. MNRJ 1989, 2013, rocky coast between Prainha beach and Brava beach (Costão do Navio, São Sebastião, SP, 23º50.067' S- 45º29.449' W), 6 m depth, E. Hajdu coll., 29/I/1999.

Additional material: MNRJ 5087, da Vila beach, left side, (Picinguaba, Ubatuba, SP), 2 m depth, R. N. Costa coll., 23/X/2001. MNRJ 5287, (Arvoredo Island, SC), 7 m depth, E. Hajdu and C.B. Lerner coll., 19/II/ 2002. MNRJ 5308, (Arvoredo Island, SC), 7 m depth, U.S. Pinheiro coll., 19/II/2002. MNRJ 5284 (Arvoredo Island, SC), 7 m depth, E. Hajdu and C.B. Lerner coll., 19/II/2002. MCN 0 383 (João da Cunha Island, Porto Belo, SC), 3 m depth, S.M. Pauls coll. . MCN 1034 (João da Cunha Island, Porto Belo, SC), 0.5 m depth, A.A. Lise coll., 22/X/1977. MCN 1035 (João da Cunha Island, Porto Belo, SC), 0.5 m depth, A.A. Lise coll., 06/ XI/1981. MCN 2235, Saco da Mulata (Galé Island, Bombinhas, SC), 12 m depth, C.B. Lerner coll., 14/II/ 1991. MCN 2278, small SW bay (Galé Island, Bombinhas, SC), 8 m depth, C.B. Lerner coll., 29/III/1991.

Diagnosis: Bright yellow live-colour and small (1-6 cm high) digits and/or fusiform processes topped by oscula.

Description:

Specimens can have few (3–4) or many digits (60–80), which are mostly erect. Digits can be single or anastomosed, cylindrical (fusiform or straight) or slightly volcaniform (rare), 1–6 cm high and 0.6–1.5 cm wide ( Figs. 1A , 2A–B ). Area coverage can be as large as 25x 15 cm, but more often about 6x 6 cm. Surface is finely conulose. Oscula are mostly apical (1.5–4 mm in diameters), but few lateral and smaller (ca. 1 mm in diameter) can occur. The colour is bright yellow in vivo, which turns into deep purple after preservation in alcohol. Consistency is soft and flexible

Skeleton: Choanosome with a delicate and irregular network of spongin fibers. They have a bark with amber colour and thickness of 25–100 Μm (average 44 Μm), and black or amber pith with thickness varying between 11 and 81 Μm (average 16 Μm) ( Figs. 2C–E , Tab. I).

TABLE I: Spongin fibres’ measurement data for Aplysina caissara Pinheiro & Hajdu, 2001 (in micrometers; S.D. = Standard Deviation and N = 30).

Specimens Locality* Fibers Piths Distribution: Provisionally endemic from southern and southeastern Brazil (24–28º S, Fig. 3 A). This area is known as the Paulista Biogeographic Province.

Ecology: The species has a typically patchy distribution, being often very rare, but reaching considerable densities at a few spots, where specimens can be found every couple of meters. Its known depth distribution is from 0.5 to 12 m. Few specimens are found at very shallow depths (0.5–3 m) in places of somewhat restricted water flow, where temperatures may reach 28º C. However, most are located in areas of large water circulation and intermittently exposed to the Central South Atlantic waters, with temperatures reaching a minimum around 13º C (Pinheiro & Hajdu, 2001).

Remarks: Among the Tropical South-western Atlantic Aplysina that possess digitiform processes, the species which most closely resembles A. caissara is A. fulva , known by its large morphologic variability along the Brazilian coast (cf. Pinheiro & Hajdu, 2001). However, A. caissara combines a bright yellow colour in life, the consistently small dimensions (digits <5 cm high) accross both known populations, the apical oscula, and a very delicate reticulation of thin spongin fibers. Contrastingly, a bright yellow colour is only seldom present in A. fulva , which frequently reaches larger dimensions (digits> 5 cm high), never possesses typically apical oscula, nor a comparably delicate reticulation of spongin fibres.

Figures

FIGURE 1: A. Aplysina caissara Pinheiro & Hajdu, 2001 — in situ (São Sebastião, SP, Brazil). B – C. Aplysina cauliformis (Carter, 1882) in situ (B. MNRJ 5462, C. MNRJ 5467, Parque Nacional Marinho dos Abrolhos, BA, Brazil). Scale bar = 1 cm.

FIGURE 2: A – E. Aplysina caissara Pinheiro & Hajdu, 2001. A – B. Holotype (MNRJ 1988, after preservation). C – D. Skeletal architecture (C. MNRJ 1675, D. MNRJ 5087). E. Spongin fibres (MNRJ 1675, 5087). Scale bars = A – B. 1 cm, C – D. 500 µm, E. 50 µm.

FIGURE 3: Map showing the distribution of Aplysina along the Brazilian coastline. A. Aplysina caissara Pinheiro & Hajdu, 2001. B. Aplysina cauliformis (Carter, 1882). C. Aplysina fistularis (Pallas, 1766). D. Aplysina fulva (Pallas, 1766). Scale bar = 500 km.