Coronula bifida Bronn, 1831

Buckeridge, John Stewart, Chan, Benny K. K. & Lin, Jih-Pai, 2019, Pampus candidus, Zoological Studies 58 (39), pp. 1-9 : 3-5

Coronula bifida Bronn, 1831 ( Figs. 2 , 3A–K )

Coronula bifida Bronn, 1831: 126 .

Coronula barbara Darwin, 1854: 421 .

Coronula diadema Hayasaka, 1933: 50 , 1934: 3, pl. 2, figs 1–3, pl. 3, figs 3–5, 1935: 1, figs 1–2.- Hatai, 1939: 262, figs 1–5.

Coronula dormitor Pilsbry and Olsson, 1951: 202 .

Coronula bifda bifda Menesini, 1968: 387 .

Coronula bifda barbara Menesini, 1968: 395 .

Coronula bifida Collareta et al., 2018: 15 .- Buckeridge et al., 2018: 4.

D i a g n o s i s: C o ro n u l a w i t h g l o b o s e s h e l l; compartments with convex longitudinal parietal ribs that often bifurcate; ribs with strong, transverse, beaded growth ridges; radii broad, flat, becoming narrower in the lowermost third; body chamber relatively shallow, sub-cylindrical; sheath equal to or less than half that of total shell height.

Distribution: Miocene-Pleistocene ( Taiwan; Japan; Calabrian; Western Europe; California; Ecuador) ( Hatai 1938 1938; Buckeridge et al. 2018).

Material: Three cut sections from one individual (NTUG110-F000023), from an upper Miocene-Pliocene stratum in SW Taiwan. Two complete specimens from Japan, including IGPS63173 ( Hatai, 1939: 395 pl. 10, figs. 1-3) and IGPS63172 ( Hatai, 1939: pl. 10, figs. 4, 5), housed at Tohoku University Museum of Natural History.

Description: Shell globose (crown-shaped), externally with prominent, convex, occasionally bifurcated longitudinal ribs; ribs crossed by narrow, beaded growth ridges, edges crenulated; basal edges of ribs crenulated; radii slightly wider at orifice than parietes at their widest, tapering to become narrow towards the base. Orifice large, hexagonal; body chamber cup-shaped, subcylindrical, extending basally to approximately half the height of the shell; basal opening less than half the diameter of the orifice; sheath less than half the total shell height.

Figures

Fig. 2. The original museum label associated with fossil barnacle specimens (NTUG110-F000023).

Fig. 3 Cut and polished sections (NTUG110-F000023) of Coronula bifida Bronn, 1831 from Plio-Pleistocene strata in southern Taiwan; (A– D) Studied and figured specimen in Hayasaka (1934: pl. 3, fig. 3); (E–F) Studied and figure specimen in Hayasaka (1934: pl. 3, fig. 4); (I–K) Unpublished slice in the same collection, used for making a thin-section (see Fig. 5A, B). Scale bars = 2 cm.