Eurypon distyli, Santos, George Garcia, França, Fernando & Pinheiro, Ulisses, 2014

Santos, George Garcia, França, Fernando & Pinheiro, Ulisses, 2014, Three new species of Eurypon Gray, 1867 from Northeastern Brazil (Poecilosclerida; Demospongiae; Porifera), Zootaxa 3895 (2), pp. 273-284 : 280-281

Eurypon distyli sp. nov.

( Figs 1 , 6–7 ; Table 1)

Type specimens. UFPEPOR 1601 (Holotype), Ponta do Seixas (07º 09' 16" S, 34º 47' 35" W), João Pessoa, Paraíba State, Brazil, depth 1 m, col. G.G. Santos, (05.XI.2013). Paratype. UFPBPOR 1620 (collected together with the holotype).

Diagnosis. Eurypon distyli sp. nov. is the only Eurypon in the Atlantic with two categories of styles and large raphides.

External morphology ( Fig. 6 ). Encrusting sponge, covering surfaces up to 2 cm ² diameter and 0.5–1.5 mm thick, growing over rocks ( Fig. 6 A). Oscules not visible. Surface hispid due to evenly distributed projecting spicules and with some bouquets of spicules irregularly distributed ( Fig. 6 B). Consistency firm and difficult to tear. Color in life is green, dark green in ethanol.

Skeleton ( Fig. 6 ). The ectosomal skeleton is absent, with tips of choanosomal the spicules externally protruding ( Fig. 6 B). The choanosomal skeleton is a hymedesmioid structure with a basal layer of acanthostyles, auxiliary styles and principal subtylostyles, are all perpendicular to the substrate ( Fig. 6 B and C). The subectosomal styles I and II are dispersed in the subectosomal region of the erect spicule skeleton.

Spicules ( Fig. 7 A–I). Choanosomal subtylostyles ( Fig. 7 A, G): long, smooth, slender, slightly curved and with bulbous base (1060–2810 / 7–18 µm); Subectosomal styles I ( Fig. 7 B, H): smooth, lightly robust and often straight (315–485 / 5–7 µm); Subectosomal style II (anisoxea) ( Fig. 7 C, I): smooth, thin and varying from straight to curved (315–437 / 3–4.5 µm); Raphides ( Fig. 7 D): usually straight, smooth and with sharp ends (121–372 / less than 0.5 µm); Acanthostyles ( Fig. 7 E–F): usually straight, fusiform, with base slightly bulbous and surface completely spined. The spines are short and curved (67–129 µm long), at the base the spines are hookshaped and in the middle region the spines are spatulate (see Fig. 7 F).

Distribution ( Fig. 1 ). Northeastern coast of Brazil, Paraíba State, Brazil.

Depth. 1 m.

Etymology. The name refers to the two size categories of subectosomal styles.

Remarks. The closest species to Eurypon distyli sp. nov. is E. radiatum from the Azores because both share the posession of two categories of subectosomal styles and one category of acanthostyle, although E. radiatum lacks choanosomal subtylostyles and raphides. Aside from these two species no other Eurypon described from the Atlantic have two categories of subectosomal styles. Other species from Atlantic that resemble Eurypon distyli sp. nov. is E. viride , both having raphides. However, E. viride has small raphides (70 µm long), tylostyles and a white color compared to large raphides (280 µm long), subtylostyles and a green color in E. distyli sp. nov. (Table 1).

Figures

FIGURE 1. Location of the collection sites of Eurypon clavilectuarium sp. nov. (1 — Rio Grande do Norte State); Eurypon distyli sp. nov. (2 — Paraíba State); and Eurypon suassunai sp. nov. (3, 4 — Bahia State).

FIGURE 6. Eurypon distyli sp. nov. (UFPEPOR 1601, holotype). A, fresh holotype taken out of the water, showing spicules; B, details of the surface; C, basal layer of spongin with echinating acanthostyles. Scale bars: A = 1 cm; B = 200 µm; C = 100 µm.

FIGURE 7. Spicule composition of Eurypon distyli sp. nov. (UFPEPOR 1601, holotype). A, subtylostyle; B, style I; C, style II; D, raphide; E, acanthostyle; F, details of the flattened spines; G, details of the base of A; H, details of the base of B; I, details of the base of C. Scale bars: A = 200 µm; B = 40 µm; C = 50 µm; D = 30 µm; E, G, H = 10 µm; F = 5 µm; I = 3 µm.