Oceanapia magna

Neto, Carlos Santos, Nascimento, Elielton, Cavalcanti, Thaynã & Pinheiro, Ulisses, 2018, Taxonomy of Oceanapia Norman, 1869 (Demospongiae: Haplosclerida: Phloeodictyidae) from the Brazilian coast, Zootaxa 4455 (2), pp. 363-376: 370-372

publication ID

https://doi.org/10.11646/zootaxa.4455.2.6

publication LSID

lsid:zoobank.org:pub:2B4688E2-A4C1-4A3F-849F-9BC657DBD9EC

persistent identifier

http://treatment.plazi.org/id/A61F8787-FF8D-4455-F6F8-F8A0FB11F83C

treatment provided by

Plazi

scientific name

Oceanapia magna
status

sp. nov.

Oceanapia magna  sp. nov.

Figures 5–6View FIGURE 5View FIGURE 6, Tables 1–2

Type locality: Brazil: Rio Grande do Norte State: Potiguar Basin. 

Type specimens: Holotype. UFPEPOR 1998 (04°44'53.7’’S 36°25’27.4’’W), Potiguar Basin , Rio Grande doGoogleMaps 

Norte State , Brazil, depth 108 m, trawl, coll. Petrobrás (23/V/2011). Paratypes. UFPEPOR 2266 and UFPEPOR 2285, collected at the type locality. 

Diagnosis. Semispherical sponge with large fistulae, large oxeas (125–408 / 2–14 µm) and sigmas (10–45 µm).

External morphology ( Fig. 5A–B View Figure ). The holotype consists of a semispherical body of 30 cm (diameter). Despite its large size, part of the specimen remained in situ at the time of collection, and it can be deduced that the size of the sponge was larger. On the upper side, there are numerous digitated fistulae of irregular shape, fragile and easily broken. Simple fistulae (0.7–6.5 x 0.5–1.8 cm, length x width) and fused fistulae (3.5–8.5 x 1.5–4 cm, length x width). Hispid and irregular surface covered by other sponges. Surface hard and firm, forming a cortex (0.5–2 cm, thickness). Colour brown when preserved (ethanol 80%), unknown in life.

Skeleton ( Fig. 5C–D View Figure ). Ectosome organic, formed by a tangencial skeleton of single oxeas and debris, supported by a subdermal reticulation of criss-crossing spicule tracts (50– 94.6 –133 µm, diameter, meshes 100– 372.2 –633 µm, diameter). The choanosomal skeleton is an irregular network of multispicular tracts (83– 174.2 –333 µm) forming irregular meshes (100– 410.1 –1165 µm) and some ascending multispicular tracts. The fistulae have an ectosomal skeleton quite differentiated, formed by multispicular tracts and irregular meshes interconnected by single spicules.

Spicules ( Fig. 6 View Figure ). Oxeas (125– 218.3 –408 / 2– 8.8 –14 µm): smooth, straight and slightly curved, with variably shaped points (acerate, hastate and blunt) ( Fig. 6A – B View Figure ). Sigmas (10– 18.2 –45 µm): smooth, thin and rare, found in the sponge body, absent in the fistulae ( Fig. 6C View Figure ).

Distribution and ecology. Known only from Potiguar Basin, Rio Grande do Norte State, Brazil, from a slope at 108 m deep ( Fig. 1 View Figure ).

Etymology. Adjective derived from Latin magna  and refers to the large size of the specimens.

Remarks. The most similar species are O. atlantica  , O. carotta  and O. oleracea  . Oceanapia atlantica  is amorphous, and its oxeas and sigmas are larger than the new species. Oceanapia carotta  has a spherical shape and its fistulae are not digitiform, and oxeas are smaller than found in O. magna  sp. nov. ( Tables 1–2). Oceanapia oleracea  has a spherical shape with fistulae on the top, and its oxeas are smaller in length and width than the new species (see Tab 1). Compared to other species of Oceanapia  in the Atlantic Ocean, Oceanapia magna  sp. nov. is distinguished from O. bartschi  , O. hondurasensis  and O. niduliformis  by the presence of strongyles. Oceanapia magna  sp. nov. differs from O. cordia  sp. nov., O. topsenti  nom. nov., O. aerea  , O. ascidia  , O. coriacea  , O. elongata  , O. fibulata  , O. isodictyiformis  , O. nodosa  , O. nodulosa  , O. peltata  , O. penicilliformis  , O. reticulata  and O. robusta  by their absence of microscleres. Oceanapia magna  sp. nov. differs from O. cancap  and O. stalagmitica  because they have toxas which are not found in the new species. Oceanapia hetcheli  nom. nov. has as spicule complement oxeas and raphidiform oxeas, while Oceanapia magna  sp. nov. has oxeas and sigmas.