Microporella Hincks 1877

Microporella sp.

(Fig. 7 B–D)

Material examined. MNCN 25.03 /4212: DA08, Gazul MV, 486–487 m depth, 24 June 2010, INDEMARES CHI- CA Project, IEO coll., on shells; MNCN 25.03 /4213: DA11, Gazul MV, 461–462 m depth, 27 June 2010, INDE- MARES CHICA Project, IEO coll., on shells.

Description. Encrusting colony, unilaminar (Fig. 7B). Autozooids hexagonal, longer than wide; frontal shield coarsely nodular with small and circular pseudopores, mainly medially and distally, usually absent proximally; few larger areolar pores (Fig. 7B). Orifice small relative to zooid size, transversely D-shaped, wider than long, proximal border straight, smooth; 4–6 delicate oral spines (the most proximal very near the orificial proximal corner) (Fig. 7 B–D). Ascopore moderately large, almost circular, slightly wider than long with reniform opening (Fig. 7C, D). Umbo absent. Single adventitious avicularium lateral, usually large and at the level of the ascopore or positioned a little below it; rostrum triangular, directed latero-distally (Fig. 7 B–D); mandible setiform and short. Ovicell not observed.

Remarks. This species differs from Microporella funbio Ramalho & López-Fé n. sp. in the zooidal size and shape, avicularium position and in having a shorter mandible. This species is similar to M. ciliata (Pallas, 1766) in the zooidal shape and large lateral avicularia, but M. ciliata has up to four oral spines (frequently five in the present material from Gazul MV), proximal border of the orifice with small teeth (smooth in Microporella sp.), and avicularium positioned slightly more proximally. Hayward & McKinney (2002) identified some Microporella colonies from the Adriatic Sea as M. ciliata. Those specimens, as the colonies studied here, have 5–6 oral spines, similar orifice shape and large adventitious avicularium, but the avicularium is positioned more proximally and the ascopore has a thick rim. Nevertheless, Kukliński & Taylor (2008) stated later that specimens identified as M. ciliata by Hayward & McKinney (2002) could belong to a different species, not M. ciliata sensu stricto. Due to the absence of ovicell and ancestrula, we prefer to maintain this species in open nomenclature, until additional material will be available.

Habitat and associated species. These specimens were found on soft bottoms with coarse and mixed sediment (sand, muddy sand), interspersed with bioclast and MDACs, where Caryophyllia sp., F. chunii, C. cidaris, Lanice sp., B. philippiana and the hydrozoa Polyplumaria flabellata Sars also occur.