Antropora cruzeiro Ramalho & Moraes n. sp.

(Fig. 3A–C)

Material examined. Holotype: MNRJBRY-1546: Brazil, Pará state (Sta #5, 01°6.16’N – 046°29.71’W), 100 m, on rhodolith, 28 September 2014, collected by Fernando Moraes & Rodrigo Moura (NHo Cruzeiro do Sul).

Etymology. Referring to the Brazilian Navy Hidro-Oceanographic ship NHo Cruzeiro do Sul and used as a name in apposition.

Diagnosis. Autozooids rectangular with piriform to oval opesia; reduced gymnocyst and granular cryptocyst with some denticles; single or paired drop-shaped avicularia placed at autozooidal corners; small and cap-shaped ovicell.

Description. Colony encrusting, multiserial, unilaminar. Autozooids elongate, somewhat rectangular, about twice as long as wide [L 349–368–377 (SD 15, N 11); W 176–198– 213 µm (SD 12; N 11)], separated by distinct grooves. Gymnocyst reduced; lateral wall granular; cryptocyst granular with tiny denticles projecting into the opesia, broader proximally and narrower laterally (Fig. 3A, B). Opesia piriform or oval [L 184–212–233 (SD 13, N 11); W 141–156– 171 µm (SD 9, N 11)], wider proximally and occupying a little more than half of the frontal area (57% on average). One or two tear drop-shaped interzooidal avicularia [L 84–91– 102 µm (SD 6, N 11)] located at autozooidal corners, directed distally (Fig. 3A–C); rostrum pointed triangular, raised from surface, condyles not observed (Fig. 3B, C). Ovicell small, wider than long [L 51–59–71 (SD 6, N 6); W 81–89– 100 µm (SD 6, N 6)], cap-shaped, almost rectangular with imperforate, seemingly smooth surface (Fig. 3C). Vicarious avicularia not observed.

Remarks. Antropora cruzeiro Ramalho & Moraes n. sp. resembles A. erectirostra Tilbrook, 1998 from the Indian Ocean (Sri Lanka) in having elongate autozooids with extensive cryptocyst, reduced gymnocyst and triangular interzooidal avicularia with a raised rostrum directed distally. However, the new species is generally smaller than A. erectirostra (autozooid: 500 x 240 µm; opesia: 250 x 160 µm; avicularia: 130 µm long), and has smooth cap-shaped ovicells (smaller and endozooidal in A. erectirostra). Four Antropora species are known from Brazil: A. hastata Winston et al., 2014, A. minor (Marcus, 1937), A. typica (Canu & Bassler, 1928a), and A. granulifera (Hincks, 1880) (Vieira et al. 2008; Winston et al. 2014; Almeida et al. 2015a). All of them have oval autozooids; A. minor has 8-shaped avicularia; A. hastata has interzooidal avicularia with elongate rostrum; A. granulifera has paired triangular avicularia placed distally and with converging rostral tips; and A. typica has a well-developed gymnocyst.