Caminella caboverdensis, Cárdenas & Vacelet & Chevaldonné & Pérez & Xavier, 2018

Cárdenas, Paco, Vacelet, Jean, Chevaldonné, Pierre, Pérez, Thierry & Xavier, Joana R., 2018, From marine caves to the deep sea, a new look at Caminella (Demospongiae, Geodiidae) in the Atlanto-Mediterranean region, Zootaxa 4466 (1), pp. 174-196 : 187

Caminella caboverdensis sp. nov.

( Figure 7 , Table 1)

Holotype. RMNH 3810 , Cape Verde, NW of São Vincente (16.9167, -25.0333), 75 m, CANCAP VI expedition (on board HMS Tydeman), station 6.174 , 22.06.1982, bottom sand, collecting gear: 1.2 m Agassiz trawl, originally identified as Isops intuta by R. van Soest (unpublished).

External morphology ( Fig. 7D ). Similar to C. intuta . Two dark brown mottled pieces (in ethanol); it is not clear if they belong to the same specimen. Very thin cortex (150 µm). Consistency fleshy, compressible.

Spicules. ( Fig. 7A–C , Table 1, Supp. Mat. Appendix 1). (a) oxeas, 800– 1525 x 8–23 µm, sometimes bent to double bent (‘wavy’); (b) dichotriaenes (rhabdome: 650–900 x 20–50 µm; protoclad: 80–150 µm, deuteroclad: 50– 230 µm); (c) spherical, immature and mature sterrasters, 35–45 µm; (d) oxyasters, 8–42 µm in diameter, 4–9 actins, actins are finely acanthose; center more or less developed; (e) spherasters, 2.5–8 µm in diameter, spiny, regular with large centrum, occasionally look like spherules.

Bathymetric range. 75 m.

DNA barcoding. COI. The holotype ( MH477614 ) had a difference of 9 bp with the COI of C. intuta , and 4 bp with C. pustula sp. nov. 28S (C1-C2). The holotype ( MH478116 ) has the same 3 bp difference with the cave specimen from Portugal and with C. pustula sp. nov. Submitted to the Sponge Barcoding Project with accession number 1778.

Etymology. Named after its type locality, the Cape Verde Islands (‘Cabo Verde’ in Portuguese).

Remarks. Although we only have one specimen, with an external and spicule morphology that closely resembles that of C. intuta , we are convinced it belongs to a new species, based on the important genetic difference found in COI (9 bp in Folmer fragment, 658 bp) and 28S (3 bp in C1-C2, 369 bp). We also noticed two spicule differences: 1) sterrasters are smaller than in C. intuta (35–45 µm versus 40–84 µm); 2) oxeas can be much more bent than in C. intuta . These genetic and morphological differences need to be confirmed with additional material. The fact that this specimen has a substantial number of immature sterrasters and few spherules suggests that it might have been living and collected in a silica-limited environment.

Figures

FIGURE 7. Caminella caboverdensis sp. nov., RMNH 3810, holotype. A. Mature sterraster. B. Oxyaster and Spherasters. C. Mature sterrasters and spherasters. D. Holotype (2 fragments).