Characella luna Dias & Santos & Pinheiro 2019, sp. nov.

Characella luna sp. nov. (Fig. 1A–I; Table 1)

Holotype: UFPEPOR 2150, Bacia Potiguar (04° 44.8945' S, 36° 25.4571' W), Rio Grande do Norte State, Brazil, depth 108 m, trawl, Box 37, col. PetrobraS, (23.V.2011).

Description of preserved specimen (Fig. 1A). Flattened fragment of 1–3 cm thick and 12 cm length. Surface iS irregular and Strongly hiSpid. ConSiStency compreSSable to hard. OSculeS not viSible. Colour in life iS unknown and purple in ethanol. The Specimen waS collected in the Same drag aS Aiolochroia crassa (Hyatt, 1875) and Stored in the Same container. It iS poSSible that the A. crassa pigmentS diScoloured the Characella Specimen. Skeleton: (Fig. 1B). EctoSome conSiSting of a denSe layer of microSclereS and Small orthotrianeS with no particular architecture, pierced by oxeaS and the cladome of dichotriaeneS. ChoanoSomal Skeleton with oxeaS and microSclereS forming a confuSed maSS lacking orientation. SpiculeS (Fig. 1C–I). OxeaS (Fig. 1C–D): (1) long, Smooth, Slender and Slightly curved (2433.1– 3200.5 –3866.3 / 36.6– 60.6 –93.3 µm), (2) Short, Smooth, thick and curved (161– 183.5 –209.3 / 6.4– 8.7 –9.6 µm); OrthotrianeS (Fig. 1E): Straight and Smooth (rhabdome: 138– 196 –333 / 12.5– 20.5 –50 µm; cladome 225– 347 –750 µm); DichotriaeneS (Fig. 1H): rare, Straight and Smooth (cladome 237.5– 323.1 –506.2 µm); AmphiaSterS (Fig. 1I): highly microSpined with 6–9 actineS (width 10.9– 22.7 –31.5 µm); MicroxeaS (Fig. 1F–G): (1) thin, long, entirely microSpined and Slightly curved (114.3– 197.5 –296.2 / 1.61– 4.1 –6.4 µm), (2) Straight, entirely microSpined and centrotylote (32.2– 40.5 –57.9 / 1.6– 2.3 –3.5 µm).

Distribution and ecology. Known only from the type locality: Off Bacia Potiguar, Rio Grande do Norte State, Brazil), at 108 m depth. No data regarding the habitat were recorded; the relatively deep diStribution (below 100 m) iS So far unuSual for memberS of the genuS.

Etymology. The Specific name honorS the Second author’S daughter Luna Maria Mariz Garcia.

Discussion. ThiS new SpecieS iS aSSigned to Characella baSed on the two categorieS of microxeaS and the predominance of amphiaSterS aS microSclereS. Currently, only three SpecieS of genuS are known for the Brazilian coaSt (Table 1). The SpecieS moSt Similar to Characella luna sp. nov. iS C. capitolii, becauSe both have two categorieS of oxeaS and two categorieS of microxeaS, one of them centrotylote. However, C. capitolii differS by not having dichotriaeneS and

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References: (1) Van Soest & Stentoft (1988); (2) Maldonado (2002); (3) Wilson (1925); (4) Mothes et al. (2007); (5) Sollas (1888); (6) Burton (1954); (7) De Laubenfels (1934);

(8) Lévi (1993); (9) Lebwohl (1914); (10) Cárdenas & Rapp (2012); (11) Van Soest et al. (2014)

for having pleSiaSterS and metaSterS. Like C. capitolii, C. poecillastroides Van SoeSt et al. 2014 ShareS two categorieS of microxeaS, one of them centrotylote. NevertheleSS, C. poecillastroides differS by the abSent of dichotriaeneS and juSt one category of oxea. The following SpecieS differS from the new SpecieS by: PreSence of one category of oxea (C. abbreviata; C. agassizi; C. aspera; C. connectens; C. flexibilis; C. laevis; C. poecillastroides; C. reticulata); AbSence of dichotriaeneS (C. abbreviata; C. agassizi; C. capitolii; C. connectens; C. ijimai; C. laevis; C. poecillastroides; C. reticulata; C. tripodaria); AbSence of orthotriaeneS (C. enae; C. flexibilis); AbSence of the Second category of microxea (C. agassizi; C. enae; C. laevis; C. reticulata); PreSence of metaSterS and abSence of amphiaSterS (C. capitolii; C. enae; C. flexibilis; C. ijimai; C. laevis; C. reticulata); PreSence of pleSiaSterS (C. abbreviata; C. capitolii). In addition, C. laevis, C. ijimai and C. reticulata differ from C. luna sp. nov. by having tyloStyleS; C. pachastrelloides differS by having anatriaeneS.