Idiotrochus

Wells, 1935, p. 532

originally described as a subgenus of Sphenotrochus, but elevated to genus level by Vaughan and Wells (1943)

Type Species

Sphenotrochus emarciatus Duncan, 1865, p.183, pl. 8, fig. 2; Original Designation

Type Specimen: Holotype; NHMUK R29276; Verified; Dry Preserved

Type Locality: Middle Miocene (Balcombian): Hamilton, Victoria, S. Australia

Type species best described by Cairns and Parker (1992: 40).

Classification

• Family: Turbinoliidae Milne Edwards and Haime, 1848

Diagnosis

Corallum asexually reproduces by transverse division, the anthocyathus cuneiform in shape, often with downward projecting costal spurs (“fishtails”); GCD up to 6.6 mm; theca imperforate; costae independent, smooth (porcellaneous) and flat, alternating in position with septa; septa hexamerally arranged in 3 cycles; 1 crown of 10 or 12 pali; columella linear-papillose.

Comparisons

Differs from Sphenotrochus in having a papillose columella, P1-2, and alternating costae.

Remarks

This genus and family was monographed by Cairns (1997), which included a phylogenetic analysis based on morphology. Four species, two of them known as fossils (see Cairns, 2004).

Distribution

• Australasia; Oligocene
• Australasia; Miocene
• Western Pacific; Recent

This page has been in preparation since 08-Oct-2008 15:21

This version was contributed by Stephen D. Cairns on 18-Nov-2008 20:31.

Page authors are: Stephen D. Cairns. Please contact the editor if you would like to contribute to the diagnosis of this taxon.

The editor is: Stephen D. Cairns