Halisarca caerulea Vacelet & Donadey, 1987

Bettcher, Larissa, Fernandez, Julio C. C., Gastaldi, Marianela, Bispo, André, Leal, Camille V., Leite, Dora, Avelino-Alves, Dhara, Clerier, Pedro H. B., Rezende, Dafinny, Gulart, Clara M. R., Pinheiro, Ulisses & Hajdu, Eduardo, 2023, Checklist, diversity descriptors and selected descriptions of a highly diverse intertidal sponge (Porifera) assemblage at Costa do Descobrimento (Bahia, Brazil), Zootaxa 5277 (3), pp. 443-489 : 478-479

Halisarca caerulea Vacelet & Donadey, 1987

( Tab. 1–2, 12; Fig. 15A–G )

Studied material. MNRJ 20520 , P.M. M. Recife de Fora (16°24.433′ S, 38°58.929′ W, Porto Seguro, BA, Brazil), intertidal, coll. Hajdu, E. & Fioravanso, A., 22 nd March 2019 . MNRJ 21169 , Recife do Mutá (16°20.721′ S 39°0.067′ W, Porto Seguro, BA, Brazil), intertidal, coll. Hajdu, E. & Avelino, D., 20 th April 2019 .

Description. Thinly encrusting (ca. 2.5 mm thick), oscules contracted in the live material due to exposure to the air during in situ photo; contracted in fixative too. Surface very smooth, shiny, with conspicuous and very regular distributed star-shaped channels. Consistency firm and cartilaginous. Color from beige to pink and lilac in vivo ( Fig. 15A ), and lighter or darker beige in fixative.

Skeleton. Ectosomal region with a collagenous cortex, ca. 25–80 µm thick. Rounded and flattened channels present in both ectosomal (up to 200 µm long) and choanosomal (up to 125 µm long) regions; average of 70 µm long to both regions ( Figs. 15B–E ).

Distribution. Previously the Greater Caribbean (Eastern Carib.— Vacelet & Donadey 1987; Vacelet 1990; Alcolado & Busutil 2012; Pérez et al. 2017. Western Carib.— Ŗtzler et al. 2000. Southwestern Carib.— Diaz 2005), Southwestern Atlantic (Fernando de Noronha and Atol das Rocas— Moraes 2011). New record—Eastern Brazil (Costa do Descobrimento, BA, Brazil).

Ecology. Growing over calcareous substrate, in a sciophilous and intertidal microhabitat, next to other sponges, sea-urchins, algae ( Caulerpa racemosa (Forssk.) J. Agardh ), and abundant filamentous organisms.

Remarks. Habit and anatomy of the specimens reported here are entirely compatible with the original description of this species by Vacelet & Donadey (1987), but deviate somewhat from aspects provided in Moraes’ (2011) description. The latter study has reported specimens with a thicker collagen cortex (250–500 µm thick) than the one found in the present study as well as in the original description by Vacelet & Donadey (1987; 25–80 µm thick; Tab. 12).

Figures

FIGURE 15. Halisarca caerulea Vacelet & Donadey, 1987, MNRJ 20520: A, specimen in life; B, transverse sections showing a wide flattened channel into the choanoseme; C, several rounded to flattened channels occurring between the ectosome and choanosome; D, a region with denser choanosome—no channels; E, and detail of choanosome with flattened and elongated choanocyte chambers.