Scorpiodinipora costulata ( Canu & Bassler, 1929 )

Martino, Emanuela Di & Taylor, Paul D., 2018, Early Pleistocene and Holocene bryozoans from Indonesia, Zootaxa 4419 (1), pp. 1-70 : 52-53

Scorpiodinipora costulata ( Canu & Bassler, 1929)

( Figs 155–157 ; Table 34)

Schizoporella costulata Canu & Bassler, 1929: 317 , pl. 36, fig. 10.

Scorpiodinipora costulata: Harmelin et al., 2012: 129 , figs 1–4; Di Martino & Taylor, 2015: 58 , pl. 54; Taylor & Tan, 2015: 29 , fig. 15G–I.

Figured material. RGM.1350588, Holocene, UPGG 041, off South Sulawesi.

Description. Colony encrusting, multiserial, unilaminar. Autozooids distinct with deep interzooidal furrows, quincuncially arranged, hexagonal, longer than broad (mean L/W = 1.33). Frontal shield convex, mamillated, with circular areolar pores widely spaced, generally visible at zooidal corners, totally hidden by calcification in some zooids, and 6–8 slightly pronounced radiating ribs between them. Orifice ovoidal, longer than broad, bearing distinct condyles placed little lower than mid-length, with anter and poster of similar size and rounded. Oral spines absent. Kenozooids, ooecia and avicularia absent.

Remarks. A single colony of Scorpiodinipora costulata has been found in our samples encrusting a gastropod shell, a substrate for which this species shows a marked preference. At the present-day, S. costulata is distributed worldwide in tropical and subtropical shallow waters ( Harmelin et al. 2012). The oldest fossil record of this species is from the early Tortonian of East Kalimantan (Di Martino & Taylor 2015). The Pleistocene specimen falls within the range of size variability reported previously for this species.

N, Number of colonies and number of zooids measured; SD, standard deviation.

Figures

FIGURES 155–157. Scorpiodinipora costulata (Canu & Bassler, 1929), RGM.1350588, Holocene, UPGG041, off South Sulawesi. 155. View of the colony encrusting a gastropod shell fragment. 156. Group of zooids. 157. Close-up of a zooid. Scale bars: Fig. 155 = 500 µm; Fig. 156 = 200 µm; Fig. 157 = 50 µm.