Gonioseris
Duncan, 1872, p. 21
Type Species
Gonioseris angulata Duncan, 1872, p. 21, pl. 7 fig. 1-5; Original Designation
Type Specimen: Syntype; n°?; Not Traced; Unknown
Type Locality: Millepore bed (Lebberston Member, Lower Bajocian according to Rawson and Wright (1995), Cloughton Wyke, near Scarborough.
Status of type specimen unclear. The collections of the British Museum keep three samples of the type locality numbered R 11337, 11340 and 11345 from the Tomes' collection. Duncan indicated that the specimen(s) came from the collection of John Leckenby. Two of those samples of the Tomes' collection are completed with plaster. I have used these specimens and also some samples of G. leckenbyi to revise the description.
Classification
Synonyms
Description
Solitary corallum with a hexagonal star-shaped outline and a very high calicular relief. No epitheca but thick costae. Radial elements are compact anastomosed, unequal, straight or slightly curved costosepta. Lateral faces ornamented with opposite carinae. No pali. Microstructure unknown but the ornamentation of septa suggest a montlivaltid microstructure. Clear hexameral (G. angulata) or pentameral (Duncan created G. leckenbyi for this) symmetry with thick S1 (the branches of the star) on which other septa are symmetrically and regularly anastomosed. Endotheca present with dissepiments, the central zone seems to be occupied by a fossa, synapticulae absent, The wall is an intercostal paratheca limited at the base of the corallum.
Remarks
The synapticulae described by Duncan are interpreted as the section of dissepiments. Two nominal species known from the same locality. Gonioseris was potentially an automobile coral.
Distribution
- Western Europe; Middle Jurassic
This page has been in preparation since 18-Aug-2009 17:49
This version was contributed by Bernard Lathuilière on 02-Apr-2011 11:03.
Page authors are: Bernard Lathuilière. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Bernard Lathuilière
|