The Echinoid Directory

• Test ovate and longer than wide with slightly angular margin. Rounded margins and subconical near centre (NB specimen may be tectonically distorted).
• Apical disc central with 4 gonopores.
• Internal buttress arrangement not recorded.
• Petals well-developed, lanceolate and closed distally. Confined to central region (about half radial length). Perradial zone raised adapically.
• Interambulacral zones narrower than ambulacral zones at ambitus.
• Periproct oral, towards the posterior margin.
• Food grooves short and unbranched.

Late Pliocene of Taiwan.

Peronella (Peronellites) ovalis Hayasaka & Morishita, 1947, by original designation

• Only the type species.

Clypeasteroida; Scutellina; Laganiformes; Laganidae; Laganinae.

Monotypic; possibly a subjective junior synonym of Rumphia or Peronella.

Hayasaka & Morishita apparently included two different species in their type series of Peronellites according to Wang (1982). Wang considered this species synonymous with Peronella. The distinction between Peronella and Rumphia resides in the interambulacral plates bounding the oral margin of the periproct (second in Peronella and fourth in Rumphia). Unfortunately the oral plating in Peronellites is not recorded, so the generic assignment of this taxon is problematic.

Nisiyama, S. 1968. The echinoid fauna from Japan and adjacent regions part II. Palaeontological Society of Japan Special Papers 13, 1-491, pls 1-30.

Wang, C-C 1982 On the fossil laganid echinoids from Taiwan, with a discussion of the genus Peronellites Hayasaka & Morishita. Acta Geologica Taiwanica 21, 140-156.