Stylopoma faceluciae, Rodrigues & Almeida & Vieira, 2020

Rodrigues, Maria J. S., Almeida, Ana C. S. & Vieira, Leandro M., 2020, New species of Stylopoma (Bryozoa, Cheilostomata) from Bahia State northeastern Brazil, Zootaxa 4786 (4), pp. 516-534 : 520-522

Stylopoma faceluciae n. sp.

( Fig. 3 A–F; Tables 1, 2)

urn:lsid:zoobank.org:act:B5435E69-AB77-445D-BE13-827A98CE2D50

Material examined. Holotype: UFBA 2774.1 , Costa dos Coqueiros, Bahia State, Brazil 12°46’ S; 38°07’ W, 25 m, coll. 2007 by LAMEB-UFBA . Paratypes: UFPE 151 , UFPE 154 , UFPE 163 , Costa dos Coqueiros, Bahia State, Brazil, 12°46’– 12°50’ S; 38°07’– 38°20’ W, 21–23 m, coll. 2007–2008 by LAMEB-UFBA; UFBA 2481.1 , UFBA 2562.1 , Costa dos Coqueiros, Bahia State, Brazil, 12°45’– 12°58’ S; 38°07’– 38°20’ W, 22–32 m, coll. 1996–2008 by LAMEB-UFBA. Additional specimens: UFBA 2767.1 , UFBA 2771.1 , UFBA 2776.1 , UFBA 2778.1 , UFBA 2781.1 , UFBA 2783.1 , UFBA 2788.1 , Costa dos Coqueiros, Bahia State, Brazil, 12°45’– 12°58’ S; 38°07’– 38°20’ W, 22–32 m, coll. 1996–2008 by LAMEB-UFBA; UFBA 2587.1 , UFBA 2772.1 , Baía de Todos os Santos, Bahia State, Brazil, 13°00’ S; 38°46’ W, 15–18 m, coll. 1996 by Orane Alves .

Diagnosis. Stylopoma with frontal wall with 60–102 pseudopores; primary orifice with sinus varying from almost parallel sided to drop-shaped, about 1/4 of the orifice length, and smooth, tall and tab-like condyles with a distal lip; 1–2 latero-oral adventitious avicularia per zooid, distally oriented, placed proximolaterally or laterally to the orifice, subtriangular in frontal view, with acute tip; vicarious avicularium sublanceolate in frontal view; ovicell bearing avicularia and with crescentic opening.

Etymology. Named after Facelúcia Barros Côrtes Souza (Universidade Federal da Bahia), in recognition of her contribution to the knowledge of the bryozoan fauna from Brazil.

Description. Colony encrusting, uni to multilaminar. Autozooids subrectangular to subpolygonal ( Fig. 3A ), limited by thin sutures. Frontal wall with coarse granules of calcification, sometimes with a median small raised umbo, with 60–102 large frontal pseudopores, marginal pores larger, distinctly elongate and well-spaced. Primary orifice transversely D-shaped ( Fig. 3B ), wider than long, distal margin smooth; with a median and almost parallel sided to drop-shaped sinus about 1/4 of the orifice length; a pair of tall proximolateral tab-like condyles [0.006 – 0.011 mm high (0.008 ± 0.012; n = 10)] with smooth margins and a distal lip. Secondary orifice slightly raised around primary orifice, developing small rounded granules. Adventitious avicularia small ( Fig. 3B, C ), single or paired, distally oriented, placed proximolaterally or laterally to the orifice; one (or rarely more) additional frontal avicularium may be present, typically proximolaterally directed, sometimes found adjacent to the zooidal margins; subtriangular in frontal view, with acute tip, with complete thin crossbar and elliptical foramen. Vicarious avicularium large ( Fig. 3C, D ), about as long and wide as autozooids and sublanceolate in frontal view. Proximal region of the vicarious avicularium semicircular; rostrum lanceolate, sometimes with a pointed and curved tip; palate occupying less than half of the rostrum length; conspicuous proximomedial constriction; crossbar complete; foramen elliptical and elongate. Ovicells prominent ( Fig. 3E, F ), partly obscuring the orifice of the maternal zooid; ooecium globose, with pseudoporous and tubercular surface and commonly bearing more than 4 subtriangular avicularia; opening crescentic, with entire proximal labellum and without a distinct suture, visible in frontal view.

Remarks. Unlike most species of Stylopoma that have vicarious avicularium spatulate in frontal view, S. faceluciae n. sp. has vicarious avicularium sublanceolate in frontal view, being easily distinguished from its congeners.

Stylopoma faceluciae n. sp. most resembles S. corallinum n. sp. and S. haywardi by having a pointed suboral umbo, single or paired latero-oral avicularia and frontal avicularia with variable orientation. Differences between S. faceluciae n. sp. and S. corallinum n. sp. include the morphology of autozooids (subrectangular to subpolygonal in S. faceluciae n. sp.; subrectangular to subquadrangular in S. corallinum n. sp.), number of frontal pseudopores (60–102 in S. faceluciae n. sp. and 38–62 in S. corallinum n. sp.), and morphology of the vicarious avicularia (sublanceolate in frontal view in S. faceluciae n. sp. and spatulate in S. corallinum n. sp.). Stylopoma faceluciae n. sp. is distinguished from S. haywardi by having subrectangular to subpolygonal autozooids (subrectangular to subquadrangular in S. haywardi ), sinus without distal constriction (with distal constriction in S. haywardi ), and condyles with a distal lip (unlipped in S. haywardi ) ( Winston & Woollacott 2009).

Among Stylopoma from Brazil, S. faceluciae n. sp. most resembles S. hastata in having subtriangular adventitious avicularia and a vicarious avicularium with conspicuous proximomedial constriction. Differences among these species include the number of frontal pseudopores (60–102 in S. faceluciae n. sp. and 42–66 in S. hastata ), sinus morphology (drop-shaped in S. faceluciae n. sp. and U-shaped in S. hastata ), condyles (squared and with distal lip in S. faceluciae n. sp. and triangular and unlipped in S. hastata ), and vicarious avicularia (monomorphic in S. faceluciae n. sp. and dimorphic in S. hastata ).

Distribution. Brazil: Bahia State. Stylopoma faceluciae n. sp. is common in Costa dos Coqueiros and Baía de Todos os Santos zones, at 15–32 m depth. This species is found encrusting hard substrata, mainly other bryozoans and fragments of corals.

Figures

FIGURE 3. Stylopoma faceluciae n. sp., UFBA 2774.1, holotype. A. Subhexagonal to sub-rhomboid autozooids. B. Primary orifice and adventitious avicularia. C. Close-up of autozooids and a vicarious avicularium. D. Group of autozooids with adventitious and vicarious avicularia. E. Group of ovicelled zooids. F. Close-up of an ovicell. Scale bars: A, D, E. 400 µm; B. 100 µm; C, F. 200 µm.