Aplysina pseudolacunosa, Pinheiro, Ulisses Dos S., Hajdu, Eduardo & Custódio, Márcio R., 2007

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 : 41-44

Aplysina pseudolacunosa sp.n. ( Figs. 22 B, 23A–B, 24, Tab. XI)

Holotype: MNRJ 5478, western coral head (patch reef, Parque Nacional Marinho dos Abrolhos, BA, 17º57'703'' S - 36º14'795'' W), 18 m depth, E. Vilanova and G. Muricy coll., 03/III/2002.

Paratypes: MNRJ 4581, stn. 34 (shallow, start: 20º24'10'' S - 39º55'35'' W, finish: 20º24'08'' S - 39º55'33'' W, off Vitória, ES), 50 m depth, Programme REVIZEE Central V coll., 15/VII/2001. MNRJ 4665, stn. 2 (13º38.98' S - 38º45.94' W, BA), 55 m depth, Programme REVIZEE Central V coll., 02/VII/2001. MNRJ 5461, coral head (patch reef, Parque Nacional Marinho dos Abrolhos, BA, 17º57'703'' S - 36º14'795'' W), 18 m depth, E. Esteves and G. Muricy coll., 03/III/2002.

Additional material: MNRJ 1549, Pirapama´s Shipwreck (Recife, PE), 20 m depth, G. Muricy coll., 11/ II/1998. MNRJ 3048, Canoa Quebrada (CE), 25 m depth, M. Guimarães coll., II/2000. MNRJ 4299, stn. 7 (shallow, Royal Charlotte Bank, BA, start: 16º19'55'' S - 38º14'39'' W, finish: 16º07'00'' S - 38º 10'20'' W), 40 m depth, Programme REVIZEE Central V coll., 30/VI/2001. MNRJ 4359, BA (15º34'08'' S - 038º49'81'' W), 20 m depth, Programme REVIZEE Central V coll., 01/VII/2001. MNRJ 4420, stn 2 (shallow, off Ponta de Castelhanos, SE of Morro de São Paulo, BA, 13º38'98'' S - 38º45'94'' W), 55 m depth, Programme REVIZEE Central V coll., 02/VII/2001. MNRJ 4669, stn 45 (shallow, ES, 20º40'70'' S - 34º35'03'' W), 108 m depth, Programme REVIZEE Central V coll., 12/VII/2001.

Diagnosis: Specimens consist of tubes or small globules covered with pronounced ridges which render the surface very irregular. Abundant, variably large digital projections stem from nearly the entire surface of specimens. Specimens always turn beige or purple upon fixation, never black.

Description of the species:

Specimens vary from globose to tubular, with a maximum of 25 cm in height and 4 cm in width (holotype), covered by ridges, which render the surface very irregular ( Figs. 23A–B , 24A ). These ridges cover the entire surface of the specimens, are always short, and surround shallow valleys. Some small, slender digitiform projections are also observed. These projections can be anastomosed or not with other such ridges or the sponge main body. The sponges possess large apical pseudoscula, 1.5 cm in diameter, sometimes with an iristype diaphragm. Small oscula are also observed on the outer sides of the sponge. In some samples, small globes with apical oscula are present in the digitiform projections. The surface is finely conulose. The colour is bright yellow and beige in vivo, turning purple or brown after preservation in alcohol, never black. Consistency was firmly compressible.

Skeleton: Choanosome with a delicate, irregular network of spongin fibers ( Fig. 24B ) with amber coloured bark and width of 22–167 Μm (average 85 Μm), and a thick, black or amber pith with 8–47 Μm width (average 20 Μm; Figs. 24C ). The presence of spongin fibers wrapped and excavated by filamentous structures, possibly fungi, was observed in some specimens (MNRJ 4420, 4665) as in Aplysina muricyana sp.n..

Distribution: Brazilian Province ( Fig. 22 B): Ceará State, Pernambuco State, Bahia State (Parque Nacional Marinho dos Abrolhos) and Espírito Santo State.

Bathymetry: Found between 18 and 55 m depth.

Etymology: The new species name, pseudolacunosa , stresses the superficial resemblance of its large inter-ridge depressions (valleys) to the surface lacunae of A. lacunosa .

Remarks: The species most closely related to A. pseudolacunosa sp.n. is A. lacunosa , which also possesses tubes with a very marked relief. A. lacunosa has a surface characterized by irregular, reticulated ridges, producing caliciform depressions of variable depth, observed even in the smallest studied specimen (MNRJ 3557). We have analyzed a series of individuals (N = 10) of different sizes of A. pseudolacunosa sp.n. and they all possess a more open arrangement of ridges and valleys, as well as globular projections, instead of the narrow caliciform depressions formed amidst the reticulate arrangement of ridges in A. lacunosa . Both species have different spongin fibers too. A. lacunosa possesses a thinner (in average 16.6 Μm), irregular pith, while in A. pseudolacunosa sp.n. they are thicker (in average 20 Μm) and regular.

Aplysina fistularis has also been observed to possess abundant projections of diverse morphologies. These are never similar to those reported here for A. pseudolacunosa sp.n., which cover the entire specimens, are always short, and produce shallow valleys.

Specimen MNRJ 4669 was dredged at 108 m and presents a different morphology. It is globose, smaller and without projections, making its assignement to A. pseudolacunosa sp.n. rather uncertain. Thus, the occurrence of this species at such a depth is still doubtful.

TABLE XI: Spongin fibres’ measurement data for Aplysina pseudolacunosa sp.n (in micrometers; S.D. = Standard Deviation and N=30).

Specimens Locality* Fibers Piths

Thinnest Mean Thickest S.D. Thinnest Mean Thickest S.D

.

* BA, Bahia State; CE, Ceará State; PE, Pernambuco State; RN, Rio Grande do Norte State.

Figures

FIGURE 22: Map showing the distribution of Aplysina along the Brazilian coastline. A. Aplysina orthoreticulata sp. n. B. Aplysina pseudolacunosa sp. n. C. Aplysina solangeae sp. n.. Scale bar = 500 km.

FIGURE 23: A – B. Aplysina pseudolacunosa sp. n. in situ, Holotype – MNRJ 5478 (Parque Nacional Marinho dos Abrolhos, BA, Brazil). C – E. Aplysina solageae sp. n. in situ. C. Fortaleza (CE, Brazil). D – E. Salvador (BA, Brazil). Scale bar = 1 cm.

FIGURE 24: A – C. Aplysina pseudolacunosa sp. n .. A. Holotype. (MNRJ 5478, after preservation). B – C. Paratype (MNRJ 4581). B. Skeletal architecture. C. Spongin fibres. Scale bars = A. 5 cm, B. 500 µm, C. 50 µm.