Haliclona (Rhizoniera) manglarensis 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 manglarensis

description: Haliclona (Rhizoniera) manglarensis sp. nov.
(Figure 13, Table 3)
Holotype. MNRJ 13052 (Vouchers: RBINS-IG 32240 -POR 13052, MHNG 85840)— Northern Point of Isla Chalaquera, Mangroves of Tumbes, Tumbes Region (03°25’31.80” S, 80°16’37.20” W), intertidal, coll. Y. Hooker, Ph. Willenz & K.M.P Monzón (27/XI/2009).
Diagnosis. The only Haliclona in the Eastern Pacific with a combination of encrusting habit, abundant lobate projections up to 3 cm high, rough surface, olive green to yellow colour alive; skeleton mostly a unispicular, isotropic reticulation, more ladder-like close to the surface.
Description (Fig. 13A, B). Encrusting with abundant lobate projections, up to 3 cm high, cylindrical or irregular, frequently bifurcate. Oscula circular, 2–5 mm diam., apical, lateral or basal on the lobate projections. Surface rough, velvety out of water. Consistency soft and bristly. Colour in life olive, becoming lighter and yellowish, towards the lobes’ apices.
Skeleton (Fig. 13C). Ectosome unspecialized. Choanosome a confused, unispicular, isotropic reticulation in the deeper parts, becoming more anisotropic close to the surface, with ill-defined uni- to bispicular primary lines irregularly connected by unispicular secondary lines. Abundant small spicules (likely juveniles), scattered all around. Mesohyl moderately pigmented, brownish. Spongin not visible.
Spicules (Fig. 13D, E). Oxeas, slender, subtly bent at centre, long acerate points, 92– 120 –140 µm x 1.0– 3.8 – 6.0 µm (n = 40 x 20).
Ecology. Intertidal, epibiotic over unidentified mangrove tree roots.
Distribution (Fig. 3E). This far only known from its type locality in the Mangroves of Tumbes area (Tumbes Region), in Peru.
Etymology. The specific epithet, “ manglarensis ”, refers to the mangrove ecosystem where the species occurs.
Remarks. Haliclona (Rhizoniera) manglarensis sp. nov. has a unispicular and isotropic reticulation in the deeper parts of the choanosome, becoming more regularly anisotropic close to the surface, with uni- to bispicular primary lines. Such an arrangement is not promptly assigned to any of the subgenera of Haliclona, being actually somewhat similar to H. (Soestella), H. (Reniera) and H. (Rhizoniera). The new species share with H. (Soestella) only the presence of ill-defined primary lines, but lacks the characteristic rounded meshes of this subgenus. In turn, the new species could also resemble Haliclona (Reniera) regarding the shared presence of unipiscular isotropic skeleton, however in H. (Reniera) the reticulation is very regular, the skeleton entirely isotropic, while the new species has a dual reticulation, irregular and isotropic in the inner parts, and anisotropic in the surface, being thus not much alike H. (Reniera). Lastly, H. (Rhizoniera) spp. commonly have a regular anisotropic, ladder-like skeleton of ascending pauci- to multispicular lines, usually lacking a specialized ectosome, and scarce spongin. This subgenus is the most similar to what is observed in the new species, except for the presence of a more isotropic skeleton in the inner parts of the choanosome and the presence of uni- to bispicular primary lines. Nevertheless, Muricy et al. (2015) amended the definition of H. (Rhizoniera) to include species with unispicular primary lines. Concurrently, the species H. (Rh.) fugidia Muricy et al., 2015 also has a skeleton similar to that in H. (Rh.) manglarensis sp. nov., isotropic inside and anisotropic close to the surface with uni- to paucispicular primary lines. Thus, the best assignment of the new species is H. (Rhizoniera).
Haliclona (Rh.) manglarensis sp. nov. has no close relatives along the Eastern Pacific (Table 3). The only other Haliclona co-occurring in the Tumbes mangroves, epibiotic on mangrove roots, is H. (Re.) parvuloxea sp. nov. (see above). The latter has a predominantly isotropic, unispicular architecture typical of its subgenus, thinly encrusting shape without lobate projections, smooth surface, and yellow colour alive. All these characters render it markedly distinct from H. (Rh.) manglarensis sp. nov.
The mangroves of Tumbes have a tropical fauna (Hooker et al. 2013), and the only tropical Haliclona spp. occurring along the Eastern Pacific are H. (Halicl.) ambrosia, H. (S.) caerulea (Hechtel, 1965), H. (Rh.) enamela, H. (G.) laubenfelsi, H. (Re.) oberi, H. (G.) perforata, H. (S.) roslynae, H. (Halicl.) sonorensis, H. (S.) spuma, and H. turquoisia (de Laubenfels, 1954). The ramose habit and longer oxeas (130–240 µm long) in H. (Halicl.) ambrosia set it apart from the new species (Dickinson 1945). Haliclona (S.) caerulea and H. (G.) perforata are easily distinguished based on the presence of sigmas as microscleres (Hechtel 1965; de Weerdt 2000). The record of H. (Rh.) enamela for Clipperton Atoll (de Laubenfels 1939) was reviewed in van Soest et al. (2011), who assigned it to H. (G.) laubenfelsi, and there is little doubt that this should be also applied to the Galápagos record also mentioned by de Laubenfels (1939). Still, the presence of toxas readily sets H. (G.) laubenfelsi apart from the new species. The bluish-green colour of H turquoisia, in conjunction with its regular, isotropic to isodictyal skeleton reinforced by multispicular tracts (Gómez et al. 2002), also characterizes it as very dissimilar to the new species. Haliclona (S.) roslynae can be distinguished by its translucent light pink colour alive, in addition to the presence of rounded meshes in the choanosome (Sim-Smith et al. 2021). In its turn, H. (Halicl.) sonorensis is very distinct. It is encrusting, with only scarce oscula, and a pinkish-violet colour alive. Besides, it has a regular iso- to anisotropic skeleton with abundant nodal spongin (Cruz-Barraza & Carballo 2006). Lastly, H. (S.) spuma is also distinguished based on its white colour alive, lack of prominent lobate projections, and presence of multispicular primary lines in the choanosome (Sim-Smith et al. 2021).
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 238-240, DOI: 10.11646/zootaxa.5087.2.1, http://zenodo.org/record/5824017