Aulospongus trirhabdostylus, Cavalcanti & Santos & Pinheiro, 2014

Cavalcanti, Thaynã, Santos, George Garcia & Pinheiro, Ulisses, 2014, Two new species of Aulospongus Norman, 1878 with a key to the Atlantic species (Poecilosclerida; Demospongiae; Porifera), Zootaxa 3827 (2), pp. 282-292: 284-288

publication ID

http://dx.doi.org/10.11646/zootaxa.3827.2.9

publication LSID

lsid:zoobank.org:pub:5156E9B1-FABE-4AA2-A338-8F5CCBED1C08

DOI

http://doi.org/10.5281/zenodo.4921523

persistent identifier

http://treatment.plazi.org/id/1F7C87E9-B317-5C60-98E1-C10F1213BB22

treatment provided by

Felipe

scientific name

Aulospongus trirhabdostylus
status

sp. nov.

Aulospongus trirhabdostylus   sp. nov.

( Figures 1–3 View FIGURE 1 View FIGURE 2 View FIGURE 3 , Table 1–2)

Type locality. Brazil, Rio Grande do Norte State, Potiguar Basin   .

Type specimens. Holotype. UFPEPOR 1517, Bacia Potiguar (04º 44.8945' S; 036º 25.4571' W), Rio Grande do Norte State, Brazil, depth 108 m, trawl, Bombona 39, col. Petrobras, (23/05/2011) GoogleMaps   . Paratypes: UFPEPOR 1519, UFPEPOR 1520 and MNRJ 17487 View Materials (collected together with the holotype); UFPEPOR 1521, Bacia Potiguar (04º 36.7198' S; 036º 46.7554' W), Rio Grande do Norte State, Brazil, depth 140 m, trawl, Bombona 29, col. Petrobras, (22/05/2011) GoogleMaps   .

Diagnosis. Aulospongus trirhabdostylus   sp. nov. is the only Aulospongus   in Atlantic with three categories of rhabdostyles.

External morphology ( Fig. 2A–D View FIGURE 2 ). Massive–arborescent with digitiform projections, 6 x 5.5 x 5 cm (length x height x width) ( Fig. 2A View FIGURE 2 ). Small oscules (0.8–1 mm) are observed on the sides or on the tips of the projections ( Fig. 2A View FIGURE 2 , arrows). Surface with bouquets of spicules irregularly distributed ( Fig. 2B View FIGURE 2 ). Fibre-bundles are inter-connected by a thin layer of spongin ( Fig. 2B–C View FIGURE 2 ). Consistency is elastic, not easily torn. Colour in life is unknown and brownish-purple in ethanol. However, the specimens were collected in the same drag as Aiolochroia crassa ( Hyatt, 1875)   and stored in the same container. It is possible that the Aiolochroia crassa   pigments painted the Aulospongus   specimens.

Skeleton ( Fig. 2C–E View FIGURE 2 ). Ectosomal skeleton composed of bouquets of anisoxeas forming irregularly distributed projections ( Fig. 2C View FIGURE 2 ). Choanosomal skeleton relatively thick, dominated by spongin fibres predominantly formed by plumo-reticulate bundles composed by rhabdostyles ( Fig. 2D View FIGURE 2 ). Each perpendicular column arising from the choanosome consists of several bundles of fibres. Fibres-bundles and tracts cored and echinated by rhabdostyles with no recognizable distribution of the three categories ( Fig. 2E View FIGURE 2 ).

Spicules ( Fig. 3A–H View FIGURE 3 ). Ectosomal auxiliary anisoxeas (399– 473.3 –547 / 3– 4.0 – 6 µm): long, thin, smooth, straight to slightly curved, with distinct tips (one sharply pointed and the other styloid) ( Fig. 3A, E View FIGURE 3 , E’); Choanosomal principal rhabdostyles (rhabdostyles I) (127– 199.5 –287 / 7– 11.1 – 14 µm): robust, slightly curved next to the basal region (rhabd), smooth base to a few spines (1–2), on the medium region to the tip composed of curved spines (hook-shaped) directed to the base, the spines near the tips are smaller and fewer than in the smaller rhabdostyles ( Fig. 3B, F View FIGURE 3 ); Echinating rhabdostyles (rhabdostyles II) (90– 116.7 –155 / 3– 6.5 – 13 µm): small, completely microspined, straight to slightly curved ( Fig. 3C, G View FIGURE 3 ); Auxiliary rhabdostyles (rhabdostyles III) (171– 217.6 –277 / 2– 6.3 – 9 µm): thin, with a slight curvature towards the end (slightly rhabdose base) and microspined (small granular spines) from the medium to the apical region ( Fig. 3D, H View FIGURE 3 ).

Distribution ( Fig. 1 View FIGURE 1 ). Brazil: Northeastern Region: Rio Grande do Norte State: off Bacia Potiguar.

Depth. 108–140 m.

Etymology. The species name refers to the presence of three categories of rhabdostyles.

Remarks. Aulospongus trirhabdostylus   sp. nov. belongs the genus by the presence of three categories of rhabdostyles, plumose choanosomal skeleton with fibres ascending to the periphery. In comparison with the species from Atlantic, Aulospongus trirhabdostylus   sp. nov. differs from A. monticularis   by its massive bulbousencrusting growth form, rhabdostyles I (completely smooth) and subectosomal extra-axial styles. Aulospongus phakelloides   is a fan-shaped sponge, with two categories of echinating rhabdostyles and absence of anisoxeas. Aulospongus samariensis   is club-shaped sponge, with one category of echinating rhabdostyles and the presence of styles. Aulospongus spinosus   is a bulbous–erect sponge, with two categories of rhabdostyles (completely smooth), while A. trirhabdostylus   sp. nov. has massive-arborescent growth form, three categories of rhabdostyles (all with spines) and presence of anisoxeas (see Table 2, Fig. 3 View FIGURE 3 ). The most similar species to A. trirhabdostylus   sp. nov. is A. gardineri ( Dendy, 1922)   from the Indian Ocean which also has three categories of rhabdostyles, but differs morphology of sponges, and in the morphology of rhabdostyles III (completely smooth in A. gardineri   ), presence of extra-axial styles, and spicules size (see Table 2). Finally, A. gardineri   is known only from the Indian Ocean, making conspecificity highly improbable.