Chalinula chelysa 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
Chalinula
Chalinula chelysa

description: Chalinula chelysa sp. nov.
(Figure 2, Table 2, Table 3)
Holotype. MNRJ 11272 (Vouchers: RBINS-IG 32239 -POR 11272, MHNG 85274)—near Playa Tina, Tortugas, Ancash Region (09º22’02.50” S, 78º25’31.00” W), 8 m, coll. Ph. Willenz & Y. Hooker (23/IX/2007). Paratypes. MNRJ 12075 (Vouchers: RBINS-IG 32240 -POR 12075, MHNG 85517)— Mocho Tres Hermanos, Ilo, Moquega Region (17º39’13.40” S, 71º21’33.10” W), depth 15 m, coll. Y. Hooker, Ph. Willenz & M. Rios (08/XI/2008); MNRJ 12080 (Vouchers: RBINS-IG 32240 -POR 12080, MHNG 85522)— Mocho Tres Hermanos, Ilo, Moquega Region (17º39’13.40” S, 71º21’33.10” W), depth 14 m, coll. Y. Hooker, Ph. Willenz & M. Rios (08/XI/2008); MNRJ 12145 (Vouchers: RBINS-IG 32240 -POR 12145, MHNG 85588)— Bahía Ancupita, Matarani, Arequipa Region (16º50’13.30” S, 72º17’28.30” W), depth ca. 9 m, coll. Y. Hooker & U. Zanabria (27/XI/2008); MNRJ 12837 (Vouchers: RBINS-IG 32240 -POR 12837, MHNG 85670)— Unnamed Locality #1, Isla Santa Rosa, Reserva Nacional de Paracas, Ica Region (14º19’11.30” S, 76º09’30.10” W), depth ca. 1 m, coll. Y. Hooker, Ph. Willenz & F. Azevedo (10/XII/2008).
Comparative material. Acervochalina variabilis Thiele, 1905: ZMB POR 3331 – syntype (slides), Juan Fernandez Archipelago, Chile.
Diagnosis. The only Chalinula in the Eastern Pacific with the combination of encrusting to cushion-shaped habit, light-yellow colour alive, anisotropic to isotropic skeleton with only few discernible primary and secondary lines, oxeas 73–169 µm, scarce spongin that never encloses the spicule tracts, and oscula mostly flat on the surface.
Description (Fig. 2A, B). Thinly encrusting, only a few centimetres wide (MNRJ 11272, 12075 and 12145), or more cushion-shaped, with occasional irregular lobate projections (MNRJ 12080, 12837). Surface smooth, punctate. Oscula, 1–2 mm wide, circular, mostly scattered, occasionally aligned on the top of short irregular ridges, flush with the surface or on the top of little bumps. Consistency soft. Colour in life beige to light-yellow.
Skeleton (Fig. 2C, D). No specialized ectosomal skeleton. Choanosome a relatively regular anisotropic reticulation, with ascending, somewhat sinuously, primary uni-, to paucispicular tracts, 1–3 spicules thick, mostly orthogonally connected by unispicular secondary tracts, and 1–2 spicules long; overall construction quite loose, with large lacunae, up to 0.8 mm in diameter, and few younger spicules scattered all around. There is a tendency of the skeleton to become isotropic in some areas. Spongin, if any, very scarce, nodal.
Spicules (Fig. 2E, F). Oxeas, fusiform, straight, or more frequently subtly bent at centre, long acerate points, 73– 129 –169 x 1.0– 5. 5–9.0 µm (Table 2).
Ecology. Specimens were found on shallow, 7–15 m deep, rocky substrates (MNRJ 11272, 12145, and 12837), or epibiotic over mytillids (MNRJ 12075, 12080); MNRJ 11272 occurred in a rich association with barnacles, brachiopods, ophiuroids, anemones, crabs, polychaetes, molluscs and other sponges. The water temperature during collections varied from 11 to 18° C.
Distribution (Fig. 3A). Known from Bahía Tortuga (Ancash Region), Isla La Vieja and Isla Santa Rosa (Ica Region), Matarani (Arequipa Region), Ilo (Moquegua Region), in Peru.
Etymology. The species name, “ chelysa ” is used as a noun in apposition, derived from the Gr. chelys (= En. turtle, Sp. tortuga), referring to the type locality (near Playa Tina, Tortugas).
Remarks. In Chalinidae, the presence of an anisotropic skeleton with uni- to paucispicular primary lines is shared by Chalinula, Haliclona (Haliclona), H. (Soestella) and H. (Rhizoniera) (de Weerdt 2002). Nevertheless, only in Chalinula secondary lines can be more than one spicule long. Chalinula chelysa sp. nov. exhibits a skeleton varying from anisotropic to subanisotropic, with secondary lines one or two spicules long, thus falling in Chalinula ’s side of the spectrum and justifying our generic assignment.
There are only four species of Chalinula previously registered along the Eastern Pacific: C. ecbasis (de Laubenfels, 1930), from California (USA); C. ignobilis (Thiele, 1905), from Punta Arenas (Chile); C. cf. molitba, from Galápagos (Ecuador); C. nematifera (de Laubenfels, 1954), from Isla Isabel and Cabo Pulmo (Mexico); and C. variabilis (Thiele, 1905), from Punta Arenas and Juan Fernandez Archipelago (Chile).
The new species is distinct from C. ecbasis, C. ignobilis and C. variabilis based on shape, colour and skeleton features (Table 3). Chalinula ecbasis is a digitate or ramose species, up to 10 cm high, with a wide variability in colour (brown, tan, purple, or lavender in life), and has a stout reticulation of spongin fibres, cored by 4–7 spicules in both primary and secondary lines (de Laubenfels 1932; Lee et al. 2007), unlike typical Chalinula spp. In turn, C. ignobilis has a thickly encrusting habit, pinkish brown colour alive with yellowish coloured base and abundant spongin enclosing the spicule tracts (Thiele 1905; Hajdu et al. 2013). On the other hand, C. variabilis is ovate to finger-shaped, reaching up to 6 cm in length, pale brown to greyish purple colour, with an irregular and dense reticulation of spongin fibres cored by oxeas up to 115 µm long (Thiele 1905). We could examine a slide of one of the syntypes of C. variabilis (ZMB POR 3331, from Juan Fernandez Archipelago), confirming its distinct skeletal organization in comparison with the new species.
In spite of sharing a similar shape, C. chelysa sp. nov. is quite unlike the species described as C. cf. molitba from Galápagos (Sim-Smith et al. 2021). The latter has a lilac colour alive and a mainly isotropic reticulation of spongin fibres cored by oxeas that are slightly smaller (103– 113 –129 µm) than in C. chelysa sp. nov (73– 129 –169µm).
Chalinula nematifera is an Indo-Pacific sponge that has recently been introduced in the Tropical Eastern Pacific (de Laubenfels 1954; Cruz-Barraza & Carballo 2008; Ávila & Carballo 2009). Chalinula chelysa sp. nov. and C. nematifera are conspicuously distinct both in ecological and morphological terms. The latter is a coral-killing species so far found exclusively in coralline areas, mostly overgrowing live corals (Ávila & Carballo 2009; Rossi et al. 2015). Such ecological preference is not present in C. chelysa sp. nov. In addition, C. nematifera has a vibrant purple colour also showing white threads standing out at the surface (de Laubenfels 1954; Cruz-Barraza & Carballo 2008; Rossi et al. 2015), contrasting with the off light-yellow colour without any threads at the surface of the new species. Their skeletons are also distinct, with a more regular anisotropic reticulation of spongin fibres in C. nematifera (Cruz-Barraza & Carballo 2008) vs. a more irregular anisotropic to subanisotropic reticulation of spicules with scarce spongin in C. chelysa sp. nov.
It is important to highlight that when Sim-Smith et al. (2021) questioned the presence of C. nematifera in the Eastern Pacific, they inadvertently missed the description provided in Cruz-Barraza & Carballo (2008). These latter authors sustained the identity of their specimens as C. nematifera based on similar dimensions of oxeas, similar skeletal features, presence of mucous and presence of the characteristic white threads in the surface of some specimens. Therefore, until further taxonomic revision, the record of this species in the Tropical Eastern Pacific is to be considered valid.
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 205-208, DOI: 10.11646/zootaxa.5087.2.1, http://zenodo.org/record/5824017