Halichondria (Halichondria) marianae, Santos & Nascimento & Pinheiro, 2018

Santos, George Garcia, Nascimento, Elielton & Pinheiro, Ulisses, 2018, Halichondriidae Gray, 1867 from the Northeastern Brazil with description of a new species, Zootaxa 4379 (4), pp. 556-566 : 558-562

Halichondria (Halichondria) marianae sp. nov.

( Figures 1–3 , Table 1, 2)

Synonymy: Halichondria cf. melanadocia (Hajdu et al. 2011: pp. 118). Halichondria sp.1 and sp.2 ( Leonel et al. 2011: pp. 35, 54).

Type specimens: Holotype. UFPEPOR 1861 , Carapibus beach (7°17’57.66”S, 34°47’52.93”W), Conde City, Paraíba State, Brazil, 0.5–1 m depth, coll. G. G. Santos, (21.II.2015).

Paratypes. UFPEPOR, 1862 collected together with the holotype; UFPEPOR 1590, 1630 Cabo Branco beach (7°08’50”S, 34°47’51”W), João Pessoa city, Paraíba State, Brazil, 1 m depth, coll. G. G. Santos, (04.XI.2013) ; UFPEPOR 1580, Tabatinga beach (7°19’07”S, 34°48’01”W), Brazil, 1 m depth, coll. G. G. Santos, (06.XI.2013) ; UFPEPOR 1638, Jacumã beach (7°11’38”S, 34°47’39”W), Brazil, 1 m depth, coll. G. G. Santos, (01.II.1014); UFPEPOR 1657, 1746, 1755, 1758, Tambaba beach (7°21’52”S, 34°47’50”W), Brazil, coll. G. G. Santos, 0.5 m depth, (17.III.2014) ; UFPEPOR 1680, Penha beach (7°10’ S, 34°45’W), Brazil, 0.5 m depth, coll. G. G. Santos, (30.I.2014) ; UFPEPOR 1797, Coqueirinho beach (7°19’14”S, 34°47’40”W), Brazil, 0.5 m depth, coll. G. G. Santos, (05.XII.2014) ; UFPEPOR 1806, Carapibus beach (7°17’57.66”S, 34°47’52.93”W), Brazil, 1 m depth, coll. G. G. Santos, (05.XII.2014) ; UFPEPOR 1823, Coqueirinho do Norte beach (6°44’21,89”S, 34°55’41,22”W), Brazil, 1 m depth, coll. G. G. Santos, (06.I.2015) ; UFPEPOR 1844, Pier de Cabedelo (6°57’39”S, 34°50’34”W), Brazil, 1 m depth, coll. G. G. Santos, (20.I.2015) .

Diagnosis. Halichondria (Halichondria) marianae sp. nov. differs from other Tropical Western Atlantic species by its combination of long and robust oxeas (large than 500 µm) and dark green color.

External morphology ( Fig. 2A–D ). Thickly encrusting to massive sponges. The preserved holotype consist of one fragment, one 9.5 x 2.5 x 3 cm (length x width x thickness). Surface rugose and rough. Regularly oscular projections or diffusely distributed along the top of the sponge ( Fig. 2A – D ) less than 4 mm in diameter, generally in rows, some with membranous rims slightly down. Some specimens with subectosomal thin canals ending in oscula. Texture firm, soft, fleshy, but compact and compressible. Color in vivo is dark green (externally) and greenish (internally), becoming grayish or brownish after fixation (ethanol 92 %).

Skeleton ( Fig. 2E–F ). Ectosome detachable from choanosome. The ectosomal skeleton is typically composed of a regular reticulation of tangentially arranged tracts (40–90 µm in diameter) of oxeas ( Fig. 2E ). Choanosomal skeleton is typically halichondrid ( Fig. 2F ), with oxeas of variable length organized in a confused fashion, showing a tendency to form ascending tracts (30–160 µm in diameter). Tracts form small brushes of oxeas perpendicular in the surface (see Fig. 2F ). Many loose interstitial spicules in the basal and deeper regions. Pigmented cells in both regions and little spongin present.

Spicules ( Fig. 3A–B , Table 1 and 2). Oxeas smooth, varying from straight to slightly curved, not divisible into two categories (90– 340.4 –800 / 5– 11 –20 µm).

Ecology. This species is often found in reef environments in sciaphylous habitats ( Fig. 2C ). Shallow water at 0.5–1 m depth.

Distribution ( Fig. 1 ). Brazil: Northeastern Region: Paraíba and Bahia State.

Etymology. Named after Mariana Carvalho, researcher from Museu Nacional, Universidade Federal do Rio de Janeiro, to her contributions to the knowledge of Brazilian sponges.

Remarks. Halichondria (Halichondria) marianae sp. nov. differs from the other 13 species recorded for the Tropical Western Atlantic by its combination of long and robust oxeas and dark green color. The most similar species is Halichondria (H.) melanadocia de Laubenfels, 1936 from Florida due to the detachable ectosome, choanosomal with spicules strewn in confusion and fusiform oxeas. However, both species clearly differ in the size of the oxeas, whereas in new species is larger than Halichondria (H.) melanadocia ( Table 2). Additionally Halichondria (H.) melanadocia have a black color whereas the new species is green (see Table 2).

Another Tropical Western Atlantic Halichondria species is Halichondria (Halichondria) corrugata Diaz, van Soest & Pomponi, 1993 , but it has smaller and thinner spicules than new species ( Table 2). Additionally, Halichondria (H.) corrugata also present color light greenish-brown or pink and lobate growth form against dark green color and thickly encrusting to massive form in the new species.

Halichondria (Halichondria) lutea Alcolado, 1984 differ from new species in many features: the oxeas are larger than in new species and the growth form is subspherical. Finally, H. (H.) lutea is orange to yellow alive with corrugated projections against dark green color with surface rugose in Halichondria (H.) marianae sp. nov.

Halichondria (Halichondria) stylata Diaz, Pomponi & Van Soest, 1993 have oxea, styles and styloids differs from the present specimen by possessing smaller spicules (see Table 2). Furthermore, the possession of color black and of styles separate if from the Halichondria (H.) marianae sp. nov.

References: (1) Carvalho & Hajdu (2001); (2) Diaz et al. (1993); (3) Alcolado (1984); (4) Hechtel (1965); (5) de Laubenfels (1936).

In Brazil, five species of Halichondria had been reported ( Table 2) and many other specimens are available in scientific collections without identification at specific level (Muricy et al. 2011). Among the species recorded for the Brazilian coast, Halichondria (H.) tenebrica is the most similar to Halichondria (H.) marianae sp. nov. in the spicules size and shape (see Table 2). The new species differs from Halichondria (H.) tenebrica in the ectosomal skeleton and color: Halichondria (H.) marianae sp. nov. presents ectosomal skeleton with a regular reticulation of tangentially arranged always multispicular tracts of spicules (40–90 µm in diameter) and with abundant pigmented cells in both regions against ectosomal skeleton with a dense tangential reticulation of pauci-multispicular tracts (30–140 µm in diameter) of Halichondria (H.) tenebrica . Finally, Halichondria (H.) tenebrica do not exhibit pigmented cells and may display the color purple in vivo and in ethanol. However, this color has not been observed in any of the specimens described herein. Halichondria (H.) marianae sp. nov. differs from all other four species recorded from Brazil ( Halichondria (H.) cebimarensis ; Halichondria (H.) magniconulosa ; Halichondria (H.) migottea and H. (H.) sulfurea ) due to the combine of long and robust oxeas and the presence of dark green color (see Table 2).

This description of Halichondria (Halichondria) marianae sp. nov. increased to 17 the number of Halichondria (Halichondria) for the Tropical Western Atlantic ( Muricy 2017).

Figures

FIGURE 1. Location of the collection site of Halichondria (Halichondria) marianae sp. nov. (1–10) and Amorphinopsis atlantica Carvalho et al. (2004) (6, 7 and 11). Numbers indicate approximate localities from which species were reported: (1) Barra de Camaratuba, (2) Coqueirinho do Norte beach and Tinto river, (3) Cabedelo, (4) Cabo Branco beach, (5) Penha beach, (6) Jacumã beach,(7) Carapibus beach,(8) Tabatingabeach, (9) Coqueirinho beach,(10)Tambaba beach, and (11) Paripe river.

FIGURE2. Halichondria(Halichondria) marianaesp. nov. A, specimenin situ(UFPEPOR 1590-paratype);B,photograph of a fresh specimen taken out of water, showing numerous oscules; C, sciaphylous habitat of holotype (UFPEPOR 1861-arrow); D, specimen taken out of water (UFPEPOR 1862-paratype); E, tangential view of ectosomal skeleton; F, cross section of the skeleton.Scale bars:A–B= 1 cm; C = 10 cm; D = 3 mm; E = 150 µm; F = 200 µm.

FIGURE 3. Halichondria (Halichondria) marianae sp. nov. (spicules from holotype-UFPEPOR 1861 in SEM). A, some variations of oxeas; B, details of tips of oxeas.Scale bars: A = 100 µm; B= 50 µm.