Desmacella stylostrongyla, Nascimento & Pinheiro, 2022

Nascimento, Elielton & Pinheiro, Ulisses, 2022, A new species of Desmacella Schmidt, 1870 (Porifera, Demospongiae, Desmacellidae) from the Northeast region of Brazil, Zootaxa 5190 (1), pp. 143-146 : 143-145

Desmacella stylostrongyla sp. nov.

( Figures 1A–H )

Type locality. Brazil, Bahia State ( Mata de São João City ) .

Type material. Holotype — UFBA 3774 , off Mata de São João City (12°26’56.3”S 37°55’31.0”W) Bahia State, Brazil, 28 m depth, coll. Andrade, Walter (II.2004).

Diagnosis. Desmacella with styles, two categories of sigma and raphides.

External morphology ( Fig. 1A ). Massive sponge, 10 x 6 cm (length x width). Hispid and worn surface, with distinct oscules (3–6 mm in diameter), compressible consistency, but fragile and easy to tear. Colour light brown (fixed in ethanol 80%).

Skeleton ( Fig. 1B ). Ectosomal skeleton without distinct spicule brushes, although individual spicules may pierce the dermal membrane heavily charged with sigmas. Choanosomal skeleton formed by large styles arranged in a halichondroid reticulation. Abundant sigmas randomly distributed. Raphides are dispersed in the choanosome and trichodragmas were observed in the secondary bundles ( Fig 1H ).

Spicules ( Figs. 1C–G; I ). Styles I (170– 353.6 –460/5– 6.7 –10 µm, length/width, average in italic): straight to slightly curved. ranging from strongyloid, acerate, rounded and mucronate tips. Styles II (270– 365 –470/ 1.2– 2.4 –3.7 µm): slender, slightly curved to slightly sinuous. Sigmas I (45– 65 –90 µm, length): larger, thin, C- or S-shaped, abundant and with smooth ends. Sigmas II (12– 18.4 –30 µm): thin, C-or S-shaped and with smooth ends. Raphides (51– 72.2 –112.2 µm, length) in trichodragmas.

Distribution. Only type locality: off Mata de São João City (Bahia State, the Northeast region of Brazil).

Etymology. The species name is given due to the presence of styles varying to strongyles.

Remarks. Desmacella stylostrongyla sp. nov. belongs to the genus Desmacella by the possession of styles and sigmas, and a skeleton consisting of plumose bundles of styles ( Ridley & Dendy 1886). It differs from Desmacella species present in the Atlantic Ocean by combining stylote megascleres (varying to strongyles), two categories of sigmas and raphides.

The new species differs from D. microsigmata Cavalcanti, Santos & Pinheiro, 2015 , D. tylovariabilis Cavalcanti, Santos & Pinheiro, 2015 , D. annexa Schmidt, 1870 , D. digitata ( Lévi, 1960) , D. grimaldii ( Topsent, 1890) , D. informis ( Stephens, 1916) , D. infundibuliformis ( Vosmaer, 1885) , D. inornata ( Bowerbank, 1866) , D. jania Verrill, 1907 , D. meliorata Wiedenmayer, 1977 , D. peachi Ferrer-Hernandez, 1914 , D. pumilio Schmidt, 1870 , D. suberitoides ( Burton, 1932) , D. topsenti (Burton, 1930) , D. vagabunda Schmidt, 1870 , D. vestibularis ( Wilson, 1904) and D. vicina Schmidt, 1870 by the presence of styles instead of tylostyles. Additionally, D. microsigmata , D. tylovariabilis . D. digitata , D. grimaldii , D. informis , D. infundibuliformis , D. inornata , D. jania , D. meliorata , D. pumilio , D. suberitoides , D. topsenti , D. vagabunda , D. vestibularis and D. vicina don’t have raphides, which are observed in the new species. Desmacella polysigmata Van Soest, 1984 that occurs in the Caribbean Sea ( Belize) is the most similar species to Desmacella stylostrongyla sp. nov., because it has stylote megascleres varying to strongyles and two categories of sigma ( Van Soest 1984). However, D. polysigmata has larger and robust styles (10– 15.2 –19 µm versus 5– 6.7 –10 µm in D. stylostrongyla sp. nov.), and sigmas I and II with half of the length (30– 37.3 –42 µm and 10– 11.6 –15 µm versus 45– 65 –90 µm and 12– 18.4 –30 µm) ( Cavalcanti et al. 2015: 367–368). Additionally, toxiform microxeas are absent in D. polysigmata ( Van Soest 1984) .

Figures

FIGURE 1. Desmacella stylostrongyla sp. nov. (UFBA 3774). A, Preserved specimen; B, thick section showing the ectosome and choanosome. C, Styles I; D, Styles II; E, detail of the ends (apex) of the styles in C and D; F, Sigmas I; G, Sigmas II; H, trichodragmas in the secondary bundles; I, trichodragma. Scale: A, 1cm; B, 300µm; C, 50µm; E, F, G, 20µm; H, 100µm; I, 50µm.