Pozziella neuhausi, Díaz-Agras, Guillermo, 2008

Díaz-Agras, Guillermo, 2008, Revision of the genus Pozziella (Porifera: Poecilosclerida) with description of three new species from the eastern Pacific *, Zootaxa 1866, pp. 69-94 : 81-89

publication ID	https://doi.org/ 10.5281/zenodo.183749
DOI	https://doi.org/10.5281/zenodo.5670644
persistent identifier	https://treatment.plazi.org/id/5614A96E-247A-FFCD-06E1-F9EFFB42D5B4
treatment provided by	Plazi
scientific name	Pozziella neuhausi
status	sp. nov.

Treatment

Pozziella neuhausi sp. nov.

( Figs. 3 View FIGURE 3 , 10–13 View FIGURE 10. A, B View FIGURE 11 View FIGURE 12 View FIGURE 13 , 19 View FIGURE 19. A )

Examined material: Holotype ZMB Por. 12646 and Paratype, ZMB Por. 12647 (preparations at O.M. deposited at ZMB). Type locality: Cocos Ridge; from 04º 30.84 N, 086º 46.23 W to 04º 30.73 N, 086º 45.94 W; depth 1087–1164 m; station 39; campaign SO 144–3a.

Description

Habitus: Incrusting and thin with 2–4 mm thickness ( Fig. 10 A, B View FIGURE 10. A, B ), holotype covering surface of 16 mm x 16 mm and paratype 16 mm x 10 mm. Yellowish white colour in alcohol. Soft, slightly flexible and fragile consistency. Rough texture. No oscula visible. Bases of both specimens with embedded sediment. Paratype with enclosed hexactinellid spicules.

Spicules

Megascleres: Large styles I, smooth, fusiform and straight or slightly curved, pointed end slightly rounded, opposite end semispherical. Some styles with enlarged axial canal ( Fig. 11 View FIGURE 11 A; 12 A–C). Style size: length 480–600 µm (M. ± S.D., 541.9 ± 54.27 µm) and width 10–17.5 µm in midregion (M. ± S.D., 13.4 ± 1.59 µm), decreasing gradually towards rounded end to 5–7.5 µm (M. ± S.D., 6.3 ± 1.3 µm) (form index: 0.025).

Very long exotyles, with spherical tyles with finely and uniformly granulated surface. Granulation extending from tyle down approximately ¼ of shaft. Rest of the spicule completely smooth. Shaft with uniform diameter and rounded lower end ( Fig. 11 View FIGURE 11 B; 12 D–F). Exotyle size: length 370–480 µm (M. ± S.D., 430.8 ± 24.48 µm), width 7.5–10 µm (M. ± S.D., 8.4 ± 1.22 µm) and tyle width 10–15 µm (M. ± S.D., 11.6 ± 1.75 µm) (form index 0.027).

Microscleres: Large, but not very abundant cyrtancistras I with semilanceolate ends with single denticle (12 H). Soft curvature with subtle angulation in the midshaft ( Fig. 11 View FIGURE 11 C; 12 G). Cyrtancistra size: height 560– 760 µm (M. ± S.D., 683 ± 56 µm) and width 25–32.5 µm (M. ± S.D., 29.4 ± 2.22 µm) (form index: 0.25). Small, thick and strong type II sigmas, generally Cshaped ( Fig. 11 View FIGURE 11 D; 12 I): height 13–20 µm (M. ± S.D., 17 ± 1.9 µm) and width 1 µm (M. ± S.D., 1.0 ± 0.0 µm) (form index: 0.42).

Skeleton

Skeletal arrangement: Choanosomic plurispicular fascicula of styles arranged in bunches near ectosome ( Fig. 13 View FIGURE 13 ). Ectosome consisting of thick layer of irregularly arranged tangential styles. Exotyles widely spaced, vertically emerging from stylar layer, tyles pointing out, not forming bunches or uniform layer. Cyrtancistras at base of sponge forming layer near the substratum. Abundant sigmas in ectosome, scattered between styles.

Distribution: Galápagos archipelago, Cocos Ridge; from 04º 30.84 N, 086º 46.23 W to 04º 30.73 N, 086º 45.94 W; depth 1087–1164 m.

Derivatio nominis: This species is dedicated to Dr. Birger Neuhaus, who collected the specimens on board the RV Sonne and provided them to us for this study.

Discussion: P. neuhausi sp. nov. has spherical tyles of the exotyles, which is shared with two other species of the genus: P. c l a v i s e p t a and P. aperta , whereas the tyles of the remaining two species, P. cerilla sp. nov. and P. lueteri sp. nov. are claviform. The exotyles of P. clavisepta and P. aperta are much shorter and thicker than those of P. neuhausi sp. nov., which are the longest and most slender of the whole genus, shown by the form indexes: 0.027 for P. neuhasi sp. nov., and for P. clavisepta and P. aperta 0.045 and 0.088, respectively. Moreover, the tyle of P. neuhausi sp. nov. is covered with a thin layer of granulae, whereas the tylar surfaces of the other four species display irregularities occasionally resembling creases. The exotyles of P. neuhausi sp. nov. neither form a uniform layer nor are they arranged in bundles in the ectosome.

The cyrtancistras of P. neuhausi sp. nov. have, like those of P. cerilla sp. nov., an angle, but in P. cerilla sp. nov. it is much more pronounced. The remaining species of the genus lack this angulation, except P. aperta , but there it occurs only in the small cyrtancistras. P. neuhausi sp. nov. cyrtancistras are situated at the base of the sponge, a characteristic that differentiates it from P. cerilla sp. nov., P. l u e t e r i sp. nov. and P. c l a v i s e p t a, in which they are dispersed in the ectosome. P. neuhausi sp. nov. clearly differs from the other four known species of Pozziella .

Pozziella lueteri sp. nov. ( Fig. 3 View FIGURE 3 , 14–17 View FIGURE 14. A, B View FIGURE 15 View FIGURE 16 View FIGURE 17 , 19 View FIGURE 19. A )

Examined material: Holotype ZMB Por 12648 (preparations at O.M. deposited at ZMB). Type locality: Cocos Ridge; from 05º 52.11 N, 087º 34.36 W to 05º 51.82 N, 087º 34.41 W; depth 760– 968 m.; station 72; campaign SO 144–3a.

Description

Habitus: 1–3 mm thick body, incrusting and rounded ( Fig. 14 A, B View FIGURE 14. A, B ), covering surface of 9 x 8 cm. Orangey yellow colour in alcohol. Soft, flexible and fragile consistency. Rough texture. Osculum in centre lateral position. Sediment embedded in base of specimen.

Spicules

Megascleres: Small styles II, smooth, fusiform and slightly curved ( Fig. 15 View FIGURE 15 A; 16 A–C), short pointed ends acerate, opposite end rounded, length 280–360 µm (M. ± S.D., 303.5 ± 26.98 µm) and width 10–12.5 µm in midregion (M. ± S.D., 11.60 ± 1.22 µm), decreasing towards rounded end to 2.5–7.5 µm (M. ± S.D., 5.20 ± 1 µm) (form index: 0.037).

Straight exotyles, short and strong. Tyle oval, dropshaped with regular wartlike formations encrusting surface ( Fig. 16 View FIGURE 16 E). Diameter of exotyle shaft decreasing towards rounded end ( Fig. 15 View FIGURE 15 B; 16 D) and smooth end ( Fig. 16 View FIGURE 16 F). Exotyle length 145–172.5 µm (M. ± S.D., 153.40 ± 6.69 µm), width 10–15 µm (M. ± S.D., 12.6 ± 1.69 µm), tyle width 20–37.5 µm (M. ± S.D., 23.70 ± 3.76 µm) (form index: 0.154).

Microscleres: Large and scarce cyrtancistras, with semilanceolate ends ( Fig. 15 View FIGURE 15 C; 16 H), regularly curved and vertically elongated Cshape, with single denticle on each end ( Fig. 16 View FIGURE 16 G, H). Cyrtancistra size: height 490–620 µm (M. ± S.D., 555.71 ± 39.10 µm) and width 20–27.5 µm (M. ± S.D., 23.93 ± 2.44 µm) (form index: 0.41). Cshaped small and strong type II sigmas ( Fig. 15 View FIGURE 15 D; 16 I): height 16–20 µm (M. ± S.D., 17.88 ± 1.27 µm) and width 1 µm (M. ± S.D., 1.0 ± 0.0 µm) (form index: 0.38).

Skeleton

Skeletical arrangement: Endosomal plurispicular fascicula of styles arranged in bunches near ectosome ( Fig. 17 View FIGURE 17 ). Ectosome consisting of a layer of irregularly arranged tangential styles and exotyles at right angles to surface, forming superficial, uniform crust with tyles pointing out. Cyrtancistras dispersed in ectosomal stylar layer with sigmas scattered in between.

Distribution: Galápagos archipelago, Cocos Ridge; from 05º 52.11 N, 087º 34.36 W to 05º 51.82 N, 087º 34.41 W; depth 760– 968 m.

Derivatio nominis: This species is dedicated to Dr. Carsten Lüter for his kindness and providing the facilities to carry out this study.

Discussion: P. l u e t e r i sp. nov. clearly differs from the other species of the genus in the form and size of its exotyles with their oval, dropshaped tyles. P. cerilla sp. nov. exotyles have similar tyles, but differ from those in P. lueteri sp. nov. because the tylar irregularities extend along ¼ of the shaft. Moreover, the exotyles of P. lueteri sp. nov. are the shortest and thickest of the whole genus, which makes this species very distinctive when comparing the form indexes, e.g. P. lueteri sp. nov. 0.154 and P. cerilla sp. nov. 0.065.

The arrangement of exotyles in the ectosome differs from all other species of Pozziella in forming a uniform layer.

The cyrtancistras of P. lueteri sp. nov., unlike those of P. cerilla sp. nov. and P. neuhausi sp. nov., are regularly curved, i.e. more similar to P. clavisepta and P. aperta , but with ends closer together than in the latter two species. P. clavisepta , P. aperta and P. lueteri sp. nov. are easily differentiated by the shape of their cyrtancistras and due to the fact that the first one has two types of sigmas, whereas the other two have only one type. According to arguments exposed above, P. lueteri sp. nov. is clearly a new species.