Ernstia solaris, 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 : 331-333

Ernstia solaris sp. nov.

( Figs 14 A–E; Table 15)

Diagnosis. Ernstia with yellow to lemon-green cormus formed by irregular and tigthly anastomosed tubes. watercollecting tubes are present. Skeleton composed of one category of triactine and one of tetractine. Actines are cylindrical with rounded to blunt tips.

Material examined (Three specimens). Holotype: MNRJ 7374 , Parcel das Tartarugas Tide Pool, Trindade Island , Espírito Santo State, 0.1 m depth, coll. F. Moraes, 19 August 2003 . Paratypes: MNRJ 7370 , Parcel das Tartarugas Tide Pool, Trindade Island , Espírito Santo State, 0.3 m depth, coll. G. Muricy, 20 August 2003 . UFRJPOR 6538, Ressurreta , Fernando de Noronha Archipelago, Pernambuco State, 15 m depth, coll. F. Azevedo and G. Rodríguez, 26 June 2011 .

Etymology. From the Latin solaris (=solar), for the yellow colour of the cormus.

Colour. Yellow to lemon-green in life and white to beige in ethanol.

Morphology. The cormus of this sponge is fragile, formed by thin, irregular and tigthly anastomosed tubes ( Fig 14 A). water-collecting tubes are present. The diameter of the osculum in vivo was 1–2 mm but after fixation it was contracted.

Anatomy. Cells with granules were not observed. The skeleton has no special organization ( Fig 14 B). It is composed of triactines and tetractines in almost the same proportion.

Spicules ( Figure 14 ; Table 15). Triactines: Equiangular and equiradiate. Actines are cylindrical and slightly undulated, with tips varying from rounded to blunt ( Fig 14 C).

Tetractines: Equiangular and equiradiate. Actines are cylindrical and slightly undulated, with tips varying from rounded to blunt ( Fig 14 D). The apical actine is slightly conical, sharp, smooth, straight, and usually shorter and thinner than the basal ones ( Fig 14 E).

Ecology. The two specimens were collected from 0.1 to 15 m of depth in shaded habitats in a tide pool.

Distribution. Fernando de Noronha Archipelago and Trindade Island.

Remarks. There are five yellow species of Ernstia : E. citrea sp. nov., E. chrysops , E. klautaue , E. naturalis and E. rocasensis sp. nov., and three whose colours are unknown: E. sagamiana , E. septentrionalis and E. sueziana . Ernstia solaris sp. nov. can be differentiated from E. naturalis , E. sueziana and E. rocasensis sp. nov. by the organisation of the cormus, which is loosely anastomosed in these three species, and tightly anastomosed in the new one. It can be distinguished from E. chrysops and E. sagamiana by the presence of diactines in those species, and from E. citrea sp. nov. and E. klautauae by the shape of the actines, which are conical in those two species, and cylindrical in E. solaris sp. nov. Ernstia septentrionalis can be distinguished from the new species because that species has cells with granules.

Specimen Spicule Length (µm) Width (µm) n

min mean sd max min mean sd max

MNRJ 7374 (H) Triactine 62.1 66.0 3.5 72.9 2.7 4.9 0.8 5.4 30 Tetractine 56.7 64.3 4.0 72.9 4.1 5.0 0.6 5.4 30 Apical 24.3 52.1 13.7 81.0 2.7 4.1 0.4 5.4 30 MNRJ 7370 (P) Triactine 54.0 60.9 4.1 67.5 4.1 4.4 0.6 5.4 20 Tetractine 43.2 60.5 5.6 67.5 4.1 4.7 0.7 5.4 20 Apical 21.6 52.9 15.3 81.0 2.7 3.4 0.7 4.1 20 UFRJPOR 6538 (P) Triactine 54.0 66.0 6.6 81.0 4.1 4.4 0.6 5.4 20 Tetractine 51.3 63.6 7.5 78.3 4.1 4.3 0.5 5.4 20 Apical 29.7 61.6 17.1 86.4 2.7 2.7 0.0 2.7 10

Figures

FIGURE 14. Ernstia solaris sp. nov. A—Specimen after fixation. B—Section. C—Triactine. D—Tetractine. E—Tetractine (ap: apical actine).