Predanophora cf. ensenada Tilbrook, 2006

Martino, Emanuela Di & Taylor, Paul D., 2018, Early Pleistocene and Holocene bryozoans from Indonesia, Zootaxa 4419 (1), pp. 1-70 : 49-50

Predanophora cf. ensenada Tilbrook, 2006

( Figs 146–149 ; Table 32)

cf. Predanophora ensenada Tilbrook, 2006: 285 , pl. 63D–F.

Figured material. RGM.1350585, Holocene, UPGG 041, off South Sulawesi.

Description. Colony encrusting, multiserial, unilaminar. Autozooids arranged in alternating rows, distinct by shallow grooves, hexagonal, longer than wide (mean L/W = 1.30). Frontal shield slightly convex, nodular, surface smooth, imperforate; marginal areolar pores not distinguished. Primary orifice suborbicular, broader than long, about 90–100 µm long by 105–110 µm wide, with the smooth, semicircular anter separated from the wide, shallow sinus by a pair of small, rounded condyles. Peristome flared, bearing a small, oval avicularium, about 65 µm long by 40 mm wide, obliquely placed and proximolaterally directed. Additional, spatulate adventitious avicularia sometimes occur on the proximal edge of zooids, randomly directed. Ooecia numerous but all incomplete; outline subcircular, broader than long.

Remarks. Three small colonies of Predanophora cf. ensenada were found in our samples. This species was originally described from the Solomon Islands, where a single fertile colony was found at Linggatu Cove entrance, off Mbanika Island ( Tilbrook 2006). Better preserved material is needed to confirm the conspecificity of our Pleistocene specimens with the Recent species. The preservation of the fossil specimens prevents the observation of some characters described by Tilbrook (2006) for P. ensenada , such as the six marginal areolar pores, the denticulate rostrum of the suboral avicularium and its complete crossbar, and the rounded, triangular foramina placed laterally on the ovicell. However, the fossil specimens show the same smooth and slightly nodular frontal shield, and a similar flared peristome with an associated suboral avicularium, as well as additional adventitious avicularia on the frontal shield.

N, Number of colonies and number of zooids measured; SD, standard deviation; *refers to incomplete ooecia (outline).

Figures

FIGURES 146–149. Predanophora cf. ensenada Tilbrook, 2006, RGM.1350585, Holocene, UPGG041, off South Sulawesi. 146. General view of the colony fragment. 147. Group of zooids. 148. Close-up of an ovicellate zooid, with incomplete ooecium, and spatulate, adventitious avicularia. 149. Close-up of an orifice. Scale bars: Fig. 146 = 500 µm; Fig. 147 = 200 µm; Fig. 148 = 100 µm; Fig. 149 = 50 µm.