Haliclona (Rhizoniera) baslaviae Bispo & Willenz & Hajdu 2022, sp. nov.
Creators: name: Bispo, André
name: Willenz, Philippe
name: Hajdu, Eduardo
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Porifera
Demospongiae
Haplosclerida
Chalinidae
Haliclona
Haliclona baslaviae

description: Haliclona (Rhizoniera) baslaviae sp. nov.
(Figure 12, Table 3)
Holotype. MNRJ 12856 (Vouchers: RBINS-IG 32240 -POR 12856, MHNG 85689)— Roquedal, Laguna Grande, Reserva Nacional de Paracas, Ica Region (14°09’11.88” S, 76°15’51.3” W), depth 3–9 m, coll. Y. Hooker, E. Hajdu & Ph. Willenz (12/XII/2008).
Diagnosis. The only Haliclona in the Eastern Pacific with a combination of smooth surface, rare oscula, blue colour alive, and an irregular anisotropic reticulation with loose uni- to paucispicular primary tracts.
Description (Fig. 12A). Small specimen, ca. 3 cm in largest diameter, thickly encrusting on an empty limpet shell. Surface smooth. Oscula rare, circular, 1 mm in diameter. Consistency soft. Colour purplish blue in life.
Skeleton (Fig. 12B). Ectosome not specialized. Choanosome an irregular anisotropic reticulation, loose uni- to paucispicular primary tracts connected by unispicular secondary tracts. Few pauci- to multispicular discontinuous tracts, perpendicular to the surface, deep in the choanosome. Choanosomal and subectosomal spaces present, 150– 780 µm in diameter. Many free spicules around. Spongin not visible.
Spicules (Fig. 12C, D). Oxeas, slender, subtly bent at centre, long acerate points, dimensions 133– 151 –169 µm x 4.0– 5.3 –6.0 µm (n = 20 x 10).
Ecology. Shallow subtidal, markedly silted habitat. Water temperature during collection was 21°C.
Distribution (Fig. 3E). Only known from its type locality at Laguna Grande (Paracas), in Peru.
Etymology. The specific epithet honours Dr. Báslavi Cóndor-Luján who, as an undergraduate, participated in our fieldwork year after year, and followed up developing her career in sponge taxonomy.
Remarks. The anisotropic, ladder-like reticulation of the new species is similar to that found in H. (Haliclona) and H. (Rhizoniera). However, the reticulation in H. (Haliclona) is supposed to be very regular, with straight primary lines, while in the new species it is more irregular with spongin not observable. Thus, H. (Rhizoniera) remains as the best assignment for the new species, especially after the amendment of the subgeneric diagnosis by Muricy et al. (2015) to allow the inclusion of species with unispicular primary lines.
This is the only blue Haliclona found in Peru. Other congeners in the Eastern Pacific showing similar colour when alive are H. (Halich.) gellindra, H. (Halich.) thielei, H. (Re.) topsenti, and H. (Halicl.) verrucosa (Thiele, 1905) (Table 3). The new species can be promptly set apart from H. (Halich.) gellindra based on the presence of a tangential ectosome and a dense, confused, subisotropic choanosomal skeleton (de Laubenfels 1932; de Weerdt 2002). The “spicule reinforced form” of H. (Halich.) thielei has an encrusting habit, 2–3 mm thick, and blue green or violet-grey colour, similarly to H. (Rh.) baslaviae sp. nov. Even so, both forms of H. (Halich.) thielei are distinct from H. (Rh.) baslaviae sp. nov. The “spicule reinforced form” has a dense and irregular skeleton, and abundant oscula; while the “spongin reinforced form” has a skeleton with abundant nodal spongin, and oscula on top of conical projections up to 3 mm high (Thiele 1905). Both patterns contrast to what is observed in H. (Rh.) baslaviae sp. nov., that has a mainly unispicular anisotropic architecture, without visible spongin, and seemingly only one, flat oscule. These features clearly set both species apart.
Haliclona (Re.) topsenti and H. (Halicl.) verrucosa are only known from the Magellanic Province and share a similar encrusting habit, though distinguished based on skeleton architecture and aspects of the oscula/surface. The former has oscula mostly on top of verrucose projections, and a dense and irregular skeleton, with occasional paucispicular tracts close to the surface (Thiele 1905). Haliclona (Halicl.) verrucosa also has oscula on top of verrucose projections, in addition to small and irregular blind verrucose projections on its surface, and abundant spongin in basal parts of the skeleton (Thiele 1905). The new species is thus distinct from all other blue(ish) Haliclona spp. known from the Eastern Pacific.
description: Published as part of Bispo, André, Willenz, Philippe & Hajdu, Eduardo, 2022, Diving into the unknown: fourteen new species of haplosclerid sponges (Demospongiae: Haplosclerida) revealed along the Peruvian coast (Southeastern Pacific), pp. 201-252 in Zootaxa 5087 (2) on pages 236-238, DOI: 10.11646/zootaxa.5087.2.1, http://zenodo.org/record/5824017