Turbicellepora yasuharai, Martino & Taylor, 2018

Martino, Emanuela Di & Taylor, Paul D., 2018, Early Pleistocene and Holocene bryozoans from Indonesia, Zootaxa 4419 (1), pp. 1-70 : 51-52

Turbicellepora yasuharai n. sp.

( Figs 150–154 ; Table 33)

Figured material. Holotype, RGM.1350586, and paratype, RGM.1350587, Holocene, UPGG 041, off South Sulawesi.

Diagnosis. Colony multilaminar. Autozooids variably polygonal with areolar pores and faint ridges in-between proximolaterally. Primary orifice with robust condyles, circular anter and U-shaped sinus. No spines. Adventitious avicularium usually single, placed transversely and laterally to the orifice, teardrop-shaped and with complete crossbar. Peristome absent, a suboral rounded umbo may occur. Interzooidal avicularia spatulate, often placed transversely and distally to an autozooid; cross-bar complete. Ooecia globular, smooth, ectooecium with large, rounded pseudopores on the frontal.

Etymology. Named after Dr Moriaki Yasuhara, ostracod researcher at University of Hong Kong (HKU), who kindly provided material and support for EDM at HKU for the Leverhulme Project of which this study is a part.

Description. Colony encrusting, multiserial, multilaminar. Autozooids distinct with shallow interzooidal furrows, chaotically arranged, variably polygonal, longer than wide (mean L/W = 1.28). Frontal shield convex, smooth with a row of small, circular, areolar pores proximolaterally, about 15 µm in diameter, separated by faint ridges. Primary orifice longer than broad, anter semicircular narrowing proximally to form a U-shaped sinus; condyles robust; oral spines and peristome absent. A rounded, suboral umbo often develops. Adventitious avicularium usually single, rarely absent or paired, small, teardrop-shaped, generally placed transversely and laterally to the orifice, sometimes distolaterally directed, crossbar complete. Spatulate interzooidal avicularia occasionally present, often oriented transversely and placed distally to an autozooid, variable in size; cystid smooth, proximolaterally bordered by marginal areolar pores; rostrum tongue-shaped and raised, palate smooth occupying more than half-length, opesia bell-shaped, crossbar complete. Ooecia globular, broader than long, smooth, the frontal ectooecium coarsely perforated by 12–18 large, round pseudopores, 10–30 µm in diameter; the proximolateral edges extending towards the proximolateral orifice margins, closure presumably subcleithral. Intramural buds observed in both autozooids and adventitious avicularia.

N, Number of colonies and number of zooids measured; SD, standard deviation; Adv, adventitious; Av, avicularium; Int, interzooidal.

Remarks. Two specimens of Turbicellepora yasuharai n. sp. were found in our samples. A few species of Turbicellepora are known from the Indo-Pacific region. Many seem to be undescribed, as shown by Tilbrook (2006) after examination of Harmer’s (1957) material attributed to ‘ T. ’ redoutei ( Audouin, 1826) in which four different orifice shapes could be distinguished. Tilbrook (2006) considered the shape of the primary orifice as the most diagnostic of characters, followed by the shape and position of the oral avicularium. Turbicellepora aculeata ( Canu & Bassler, 1929) has a deep peristome enclosing a proximal suboral, elliptical avicularium, a narrow sinus, and narrow interzooidal avicularia; T. ampla ( Kirkpatrick, 1888) has a deep V-shaped sinus surrounded by a flared peristome, always paired lateral avicularia, and papillate frontal ovicell pores; ‘ T. ’ ovioris Tilbrook, 2006 is characterized by its egg-shaped orifice and the lack of oral avicularia; ‘ T. ’ redoutei has a narrow orificial sinus, and suboral avicularium with up-curved rostra, placed on a protruding cystid partly hiding the orifice. These features distinguish Turbicellepora yasuharai n. sp. from previously described species of Turbicellepora in this region.

However, the presence of Turbicellepora sensu strictu in the tropical Indo-West Pacific has been questioned ( Tilbrook 2006). Some Indo-West Pacific species of Turbicellepora (‘ T. ’ redoutei and ‘ T. ’ ovioris) differ from the European type species of the genus, T. coronopus (Wood, 1884) , in having ovicells closed by the operculum. The type of ovicell closure varies among species also in other genera (e.g. Schizomavella ) and can be ascertained only when living reproducing colonies are observed ( Berning & Ostrovsky 2011, p. 514).

Figures

FIGURES 150–154. Turbicellepora yasuharai n. sp., Holocene, UPGG041, off South Sulawesi. 150–153. Holotype, RGM.1350586. 150. General view of the colony fragment. 151. Close-up of a zooid and two interzooidal avicularia. 152. Close-up of two ovicellate zooids. 153. Close-up of a zooid with a well-preserved orifice, suboral umbo, and broken adventitious avicularium. 154. Paratype, RGM.1350587, general view of the colony. Scale bars: Fig. 150 = 200 µm; Figs 151–153 = 100 µm; Fig. 154 = 400 µm.