Clathrina zelinhae, Klautau, 2017

Klautau, Michelle, 2017, Taxonomy and phylogeny of calcareous sponges (Porifera: Calcarea: Calcinea) from Brazilian mid-shelf and oceanic islands, Zootaxa 4311 (3), pp. 301-344 : 322

Clathrina zelinhae sp. nov.

( Figs 9 A–D; Table 10)

Diagnosis. white Clathrina with irregular and tightly anastomosed tubes and two categories of triactines: one cylindrical, smaller and more abundant, and the other conical, larger and rare.

Material examined (Four specimens). Holotype: UFRJPOR 6627, Donzelinha Tide Pool , Rocas Atoll , Rio Grande do Norte State, 3 m depth, coll. A. Padua, 0 6 July 2011 . Paratypes: UFRJPOR 6628, same data as holotype. UFRJPOR 6686, Barretinha, Rocas Atoll , Rio Grande do Norte State, 3 m depth, coll. A. Padua, 18 July 2011 . Additional material: UFRJPOR 8773, Cabeço da Tartaruga, São Pedro e São Paulo Archipelago, 8–17 m depth, coll. F. Azevedo and G. Rodríguez, 17 June 2011 .

Etymology. In tribute to Maurizélia de Brito Silva (Zelinha), manager of the Rocas Atoll Marine Biological Reserve, who has dedicated most of her life to support scientific research and to protect the natural resources in the atoll.

Colour. white in life and beige in ethanol.

Morphology. Specimens are soft, fragile and encrusting. Cormus is composed of thin, irregular and tightly anastomosed tubes ( Fig 9 A). water-collecting tubes were not observed. Anatomy. Cells with granules were absent. The skeleton has no special organization ( Fig 9 B). It is composed of two categories of triactines. The cylindrical and smallest is very abundant, while the conical and largest is very rare.

Spicules ( Figure 9 ; Table 10). Triactine I: Equiangular and equiradiate. Abundant. Actines are cylindrical, straight, with blunt to sharp tips ( Fig 6 C).

Specimen Spicule Length (µm) Width (µm) n

min mean sd max min mean sd max

UFRJPOR 6627 (H) Triactine I 85.0 95.8 5.4 107.5 2.5 3.9 1.0 7.5 30 Triactine II 255.0 271.1 13.2 290.0 17.5 20.8 2.2 25.0 0 9 UFRJPOR 6628 (P) Triactine I 72.5 100.8 12.1 122.5 3.8 5.3 1.4 8.8 30 Triactine II 275.0 325.6 31.6 365.0 15.0 22.2 4.3 27.5 0 8 UFRJPOR 6686 (P) Triactine I 97.5 110.1 6.2 125.0 5.0 6.5 1.4 11.3 30 Triactine II 255.0 333.3 42.4 425.0 17.5 25.4 3.3 35.0 29 Triactine II: Equiangular and equiradiate, large and rare. Actines are conical, straight, with blunt tips ( Fig 9 D).

Ecology. Specimens of Clathrina zelinhae sp. nov. were collected in a narrow channel (Barretinha) and in a small tide pool (Donzelinha) in Rocas Atoll. This species was also present in SPSPA in vertical shaded microhabitats in the subtidal region, from 3 to 17 m of depth, frequently on calcareous algae.

Distribution. Rocas Atoll and São Pedroe São Paulo Archipelago, off NE Brazil.

Remarks. Currently there are three species of white Clathrina with two size categories of triactines: C. clara Klautau & Valentine, 2003 from Christmas Islands, western Australia; C. antofagastensis Azevedo et al., 2009 from Chile; and possibly C. sororcula Van Soest & De Voogd, 2015 from Indonesia (the authors considered one size category but mentioned that this species could have two size categories of triactines). Clathrina zelinhae sp. nov. can be distinguished from all the others because the smaller category (triactine I) has cylindrical actines in this species, while in the others they are conical. Besides, it has larger spicules [Triactine I (mean): 95.8 to 110.1 µm/ 3.9 to 6.5 µm; Triactine II (mean): 271.1 to 333.3/ 20.8 to 25.4 µm] than C. antofagastensis [Triactine I (mean): 39.6 to 49.5/ 5.0 to 6.6 µm; Triactine II (mean): 100.0 to 108.8/ 10.4 to 10.8 µm]. It was not possible to compare the size of our spicule categories with those from C. sororcula because the spicules of the latter were measured as one single category. Nonetheless, it is possible to observe that the largest spicules of C. sororcula are shorter (201 µm) than our largest spicules (290 µm to 425 µm).

Figures

FIGURE 6. Clathrina insularis sp. nov. A—Holotype after fixation. B—Section. C—Triactine I. D, E—Triactine II (regular). F—Triactine II (subregular).

FIGURE 9. Clathrina zelinhae sp. nov. A—Holotype after fixation. B—Section. C—Triactine I. D—Triactine II.