Pachychalina lupusapia 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
Niphatidae
Pachychalina
Pachychalina lupusapia

description: Pachychalina lupusapia sp. nov.
(Figure 16, Table 3, Table 8)
Holotype. MNRJ 11357 (Vouchers: RBINS-IG 32239 -POR 11357, MHNG 85356)— Islote Santo Domingo, Islas Lobos de Afuera, Lambayeque Region (06°55’09.80”’S, 80°44’09.40” W), depth 15 m, coll. Ph. Willenz & Y. Hooker (05/X/2007). Paratypes. MNRJ 13676 (Vouchers: RBINS-IG 32241 -POR 13676, MHNG 85914)— Puerto Rico, Bayóvar, Bahia Sechura, Piura Region (05°46’49.70” S, 81°04’04.70” W), depth 10 m, coll. Y. Hooker, M. Rios & Ph. Willenz (09/XII/2009); MNRJ 13687 (Vouchers: RBINS-IG 32241 -POR 13687, MHNG 85925)— La Cabrillera, Isla Foca, Piura Region (05°12’09.30” S, 81°12’39.90” W), depth 15 m, coll. Y. Hooker, M. Rios & Ph. Willenz (11/XII/2009). Additional topotypical material deposited in collections. MNRJ 11349 (Vouchers: RBINS-IG 32239 -POR 11349, MHNG 85348)— Islote Santo Domingo, Islas Lobos de Afuera, Lambayeque Region (06°55’09.80”’S, 80°44’09.40” W), depth 14 m, coll. E. Hajdu (05/X/2007).
Comparative material. Pachychalina tenera Thiele, 1905: ZMB POR 3329 — syntype (slides), Punta Arenas, Chile.
Diagnosis. The only Pachychalina in the Eastern Pacific with a thickly encrusting habit and attaining large dimensions, with abundant lobes bearing apical oscula, surface punctate, light grey colour alive with purple or violet tinges; choanosome with pauci- to multispicular primary tracts (up to 55 µm thick), connected by secondary uni- to paucispicular tracts; oxeas 90–164 µm in length.
Description (Fig. 16A, B). Thickly encrusting, 3–8 mm thick, occupying areas as large as 1 m, nearly flat, or bearing abundant, commonly short, cylindrical or volcaniform (0.5–1.0 cm high), seldom long, digitiform lobes (2.5–3.0 cm high). Oscula, 0.5–3.0 mm in diameter, circular, usually apical on lobes. Surface punctate. At places, mainly at margins, convergent subectosomal canals are seen in in situ images, but it is not clear they converge towards oscula. Consistency easily compressible, but slightly resilient. Colour in life light grey, with a hint of purple or violet.
Skeleton (Fig. 16C–E). No specialized ectosomal skeleton, only a few tangential oxeas strewn randomly amidst the orthogonal terminations of the main choanosomal tracts. Choanosomal architecture anisotropic at parts, or seemingly isotropic, with pauci- to multispicular primary longitudinal tracts (up to 55 µm thick), connected by short secondary uni- to paucispicular tracts inserted at various angles to the former. Spicule density decreases towards the periphery. Spongin is scarce.
Spicules (Fig. 16F, G). Oxeas, slender, mostly subtly bent at centre, long, acerate points, dimensions 90– 137 – 166 x 1.6– 5.9 –9.0 µm (Table 8).
Ecology. Specimens seen in nearly plane, often vertical, rocky walls, at 15 m depth. They were associated to sea urchins (cf. Paracentrotus), ophiuroids, chitons, tunicates, blennies, algae, and large barnacles. Water temperature during collection of the holotype was 16 °C.
Distribution (Fig. 3F). Known only from Bahía de Sechura (Piura Region) and Islas Lobos de Afuera (Lambayeque Region), in Peru.
Etymology. The epithet “ lupusapia ” is used as a noun in apposition derived from the L. lupus (= wolf) and Gr. apios (= far away), making reference to the type locality Islas Lobos de Afuera.
Remarks. There are only two species of Pachychalina reported from the Eastern Pacific: P. acapulcensis Wilson, 1904, from Mexico, and P. tenera Thiele, 1905 from southern Chile and Argentina (Table 3). Pachychalina acapulcensis is described as an erect lamella, bearing several lobes, a conulose surface, and oxeas 60–100 x 2–5 µm (Wilson 1904). Such features are enough to distinguish it from P. lupusapia sp. nov. Pachychalina. acapulcensis has a skeleton that is very similar to species of Callyspongia (Cladochalina), such as C. (Cl.) fibrosa, i.e., with stout spiculofibres encased by spongin and a complex reticulation of smaller fibres. In fact, several species previously described under Pachychalina in the Indo-Pacific have been transferred to Callyspongia (Cladochalina) (Desqueyroux-Faúndez 1984; de Voogd 2004). We propose the transfer of P. acapulcensis to the Callyspongiida, classified as Callyspongia (Cladochalina) acapulcensis comb. nov.
The only other Pachychalina in the Eastern Pacific is P. tenera from the Magellanic area. The holotype is encrusting, up to 10 mm thick, soft and delicate in consistency (Thiele 1905). We examined a slide of the skeleton of the syntype (ZMB POR 3329), that has an anisotropic architecture, with both primary and secondary multispicular tracts stouter than those of P. lupusapia sp. nov. In addition, secondary tracts in P. lupusapia sp. nov. are much shorter and more slender than in P. tenera, creating a tighter skeleton that is also more disorganized. Pachychalina tenera was also recorded for the Patagonian coast of Argentina (Gastaldi et al. 2018), where it was found as encrustations bearing digitiform or volcaniform projections, extremely soft but resilient in consistency, violet coloured alive, and with a similar skeletal architecture to the holotype of P. tenera. Thus, both Chilean and Argentinean populations of P. tenera are clearly distinct from P. lupusapia sp. nov.
Although classified in another genus, H. (S.) spuma is also similar to the new species based on the shared presence of multispicular tracts in the choanosome and punctate surface. Nevertheless, the primary tracts in H. (S.) spuma are subanisotropic, with ill-defined primary tracts, cavernous choanosome, and white to cream colour alive (Sim-Smith et al. 2021). While P. lupusapia sp. nov. has an anisotropic reticulation, with well-defined primary tracts, choanosome not cavernous and a light purplish grey colour alive. In addition, the surface looks more heavily punctate in P. lupusapia sp. nov.
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 245-247, DOI: 10.11646/zootaxa.5087.2.1, http://zenodo.org/record/5824017