Haliclona (Reniera) caduca Hajdu, Desqueyroux-Faúndez, Carvalho, Lôbo-Hajdu and Willenz, 2013

Hajdu, Eduardo, Desqueyroux-Faúndez, Ruth, Carvalho, Mariana De Souza, Lôbo-Hajdu, Gisele & Willenz, Philippe, 2013, Twelve new Demospongiae (Porifera) from Chilean fjords, with remarks upon sponge-derived biogeographic compartments in the SE Pacific, Zootaxa 3744 (1), pp. 1-64 : 20-21

Haliclona (Reniera) caduca Hajdu, Desqueyroux-Faúndez, Carvalho, Lôbo-Hajdu and Willenz sp. nov.

( Figs. 2C , 5A–B ; Tab. 4)

Haliclona caduca Desqueyroux-Faúndez et al. (2009, nomen nudum) in Willenz et al. (2009: 150)

Type material. Holotype. IZUA-POR 142, northern side of the entrance of Quintupeu Fjord (field number Ch2004Por 86, 42º09’49.32”S – 72º26’40.32”W, Chilean Patagonia ), 14 m depth, coll. E. Hajdu, G. Lôbo-Hajdu and Ph.Willenz, 21 April 2004 ―fragments from the holotype: MHNG 61493 , MNRJ 8233 and RBINSc-IG 32231- POR 8233 .

Comparative material. Reniera altera Topsent, 1901 [ RBINSc-IG 10131 POR 041 , syntype, = Haliclona ( Reniera) altera ]. Reniera cinerea var. porosa Topsent, 1901 [RBINSc-IG 10131 POR 042 , syntype, = Haliclona ( Reniera) topsenti ( Thiele, 1905) ]. Reniera ignobilis Thiele, 1905 ( ZMB POR 3324 , holotype, = Chalinula i. comb. nov.). Reniera macropora Thiele, 1905 [ ZMB POR 3316 , holotype, = Haliclona (cf. H.) m.]. Reniera siphonella Thiele, 1905 [ ZMB POR 3312 , holotype, = Haliclona (subgenus unknown) s.]. Reniera sordida Thiele, 1905 [ ZMB POR 3321 , holotype, = Haliclona ( Reniera) s.].

Diagnosis. The only massive, non-pedunculate, Temperate South American Haliclona (Reniera) with oxeas commonly smaller than 100 µm.

Description ( Fig. 2C ). The sponge bear variably large (1–3 cm high), single or paired projections which can be volcaniform, globular or conical. Every projection is topped by a circular osculum (2–3 mm in diameter) bearing a short, delicate, translucid, peripheric iris-type membrane. Smooth surface, extremely soft and fragile consistency. Live colour: whitish to pink, light beige when preserved in ethanol.

Skeleton ( Fig. 5A ). Ectosomal skeleton, an irregular, tangential, mostly unispicular, isodictyal to subisodictyal reticulation. A few tangential paucispicular tracts are seen, bound by slightly larger amounts of spongin when compared to their surroundings. A few larger, ill-defined polygonal meshes are also apparent, comprising several of the smaller polygonal ones and also being marked by slightly larger amounts of spongin. In between the tangential oxeas there exist clusters of 2–3 divergent oxeas, visible on the surface of the sponge as a discontinuous hispid layer. Choanosomal skeleton a unispicular isodictyal to subisodictyal network forming polygonal meshes. Isolated unispicular tracts of oxeas are occasionally visible but could have been formed by rupture of former meshes. Spongin is highly inconspicuous, nodal only.

Spicules ( Fig. 5B ). Megascleres, oxeas, fusiform, slightly bent, with variably shaped points (strongyloid, mucronated, conical, sharp), 85– 101.4 –113 µm in length and 5– 7.9 –10 µm thick.

Distribution and ecology. This species is known only from its type locality. Quintupeu Fjord (northern side of the entrance, 13.5 m depth), epibiontic on Mytilus chilensis .

Etymology. The name ‘caduca’ is derived from the consistency of the species, which is fragile, crumbly (caducus = Latin for falling, deciduous).

Remarks. Table 4 briefly summarises the descriptive information available for species of Haliclona (Reniera) , Haliclona spp. (subgenera unknown), Haliclona spp. (new subgeneric assignments) and Chalinula ignobilis ( Thiele, 1905) comb.nov. (for Reniera ignobilis ) hitherto recorded from the Temperate South America and Southern Ocean Realms, and thought to be possibly closely related to the new species. Many species cannot be confidently assigned to a subgenus without revision of their type material, as architectural characters are not readily made out from the available descriptions. This is the case of Haliclona eterospiculata , H. gemina , H. rugosa , H. scotti , H. siphonella and H. texta , all of which treated as subgenus unknown. For some, new subgeneric assignments were tentatively proposed on the basis of published descriptions. This group includes Haliclona (cf. Gellius) subglobosa, Haliclona (cf. H.) bilamellata, H. (cf. H.) clara, H. (cf. H.) divulgata, H. (cf. H.) flaccida, H. (cf. H.) macropora , H. (cf. H.) penicillata, H. (cf. H.) proletaria, H. (cf. H.) spinosella, H. (cf. H.) verrucosa, H. (cf. H.) virens, H. (cf. Halichoclona) foraminosa and H. (cf. Soestella) inepta. Several of the latter had originally been classified within Reniera , but are thought to possess important distinctive architectural features when compared to H. ( Reniera ) s.s., with unispicular isodictyal reticulation, as observed in both new species described here. Among those, H. (cf. H.) divulgata, H. (cf. H.) flaccida, H. (cf. H.) macropora , H. (cf. H.) penicillata, H. (cf. H.) proletaria, H. (cf. H.) spinosella, H. (cf. H.) verrucosa, H. (cf. H.) virens and H. (cf. Halichoclona) foraminosa were all originally reported with architectures reinforced by variably stout longitudinal tracts united by uni- to paucispicular transverse lines one spicule long, which confer them a Haliclona (Haliclona) character, or, in the case of the latter species, where even stouter, spongin reinforced basal tracts occur and the sponge has been reported to be brittle, a Haliclona (Halichoclona) character. Unfortunately, even in a few cases where type material has been available to us, it has been in the form of dissociated spicules only, thus preventing a definitive assessment of best subgeneric placements for Haliclona (cf. H.) macropora , Haliclona (cf. Reniera ) sordida and Haliclona (subgenus unknown) siphonella .

Haliclona (Reniera) caduca sp. nov. appears quite distinct from several species listed in Table 4, due to its rather larger and stouter oxeas. Actually, some of these oxeas are so large, that it remains to be established whether species such as H. (R.) altera , with oxeas nearly 400 µm long, really belong in this group. Species with comparatively small oxeas and a Reniera - type architecture, or where the architecture could not be made out from available descriptions, are Haliclona (R.) delicata , H. (s. u.) gemina , H. (R.) pedicelata and H. (s. u.) texta . The first of these has been described with oxeas characteristically pointy, not variably ended as in the new species, and to be composed of tiny little encrusting cushions 1–2 cm in diameter, which further distinguish it from the massive shape of the Chilean species. Another two of these species, described by Sarà (1978), albeit impossible to assign to a subgenus with confidence, approach the new species as far as their oxeas are considered. Haliclona (s. u.) gemina is plate-like, with a central crateriform depression, and elastic in consistency, and was reported to bear main choanosomal tracts 15–40 µm thick, all these being features not found in the new species. Haliclona (s. u.) texta is erect, bushy, over 20 cm high, also elastic, and bearing a generally multispicular reticulation of variably thick tracts, again quite distinct from the overall shape and architecture of H. (R.) caduca sp. nov. Another species that gets close to the new species is Cuartas’ (1986b) H. (R.) pedicelata , but in addition to its already distinguishing lamellate-pedunculate shape, it also has multispicular choanosomal tracts and oxeas in two size classes. Haliclona (R.) caduca sp. nov. is thus considered a clear new species.

A few remarks on Chalinula ignobilis comb.nov. are worth adding here. We had the opportunity to examine a tiny fragment from its holotype and an apparently original preparation of coloured sections. From the former we were able to make a preparation of dissociated spicules’ and offer a new set of measurements for its oxeas, and from the latter, to verify from a single spot the diagnostic feature for Chalinula , viz. secondary tracts at least two spicules long, as well as the abundant spongin coating referred to by Thiele (1905). In spite of quite comparable external morphology and spicules, this species is readily distinguished from Haliclona (R.) caduca sp. nov. by its Chalinula -type of architecture.

Figures

FIGURE 2. In situ photographs of Suberites cranium sp. nov. (A, IZUA-POR 140, paratype), Tethya melinka sp. nov. (B, IZUA-POR 141, holotype), Haliclona caduca sp. nov. (C, IZUA-POR 142, holotype), Oceanapia guaiteca sp. nov. (D, IZUA- POR 144, holotype; E, MNRJ 8975, paratype), Oceanapia spinisphaera sp. nov. (F, RBINSc-IG 32233-POR 9913, holotype). Scale bars: A–B, 5 cm; C, D, F, 2 cm, E, 1 cm.

FIGURE 5. Skeletal architecture and spicule complement of Haliclona (Reniera) caduca sp. nov. (A–B, IZUA-POR 142, holotype), Oceanapia guaiteca sp. nov. (C–E, MNRJ 10927and 10943, paratypes), and Oceanapia spinisphaera sp. nov. (F–I, MHNG 52781, fragment from holotype). H. (R.) caduca sp. nov.: A, skeletal architecture in transverse view; B, spicules. O. guaiteca sp. nov.: C, skeletal architecture in tangential view; D, oxeote and strongylote megascleres; E, sigma microsclere. O. spinisphaera sp. nov.: F, skeletal architecture on tangential view; G, skeletal architecture on transverse view; H, oxeote megascleres; I, sigma microsclere. Scale bars: A, 200 µm; B, D, H, 100 µm; C, F–G, 500 µm; E, I, 10 µm.