Dactylastrea
d'Orbigny 1849, p.9
Dactylastrea d'Orbigny 1849, p.9 is a junior synonym (available and invalid), see Thamnasteria Lesauvage, 1823, p. 243.
Type Species
Alveopora incrustata Michelin p. 111, pl. 25 fig. 8; Monotypy
Type Specimen: Syntype; ; Lost; Unknown
Type Locality: The Michelin’s original came from Mécrin (Middle Oxfordian, Meuse; France).
The syntype from Michelin is lost. The taxonomic position adopted here and the description is based on samples identified as Dactylastrea incrustata by d’Orbigny, the author of the genus (MNHN n° A09565).
Classification
Description
Ramose thamnasterioid corallum. Branches show some epithecal rings covering the calices. Top of branches rounded or flat. Intracalicular increase. Radial elements compact or subcompact biseptal sheets, anastomosing, straight, curved, shifted or sinuous, unequal in length, not very unequal in thickness. Distal edge with small regular blunt teeth visible in some places, inner edge generally attenuated when not anastomosed, lateral faces with pennules-like structures (compatible with those described for Thamnasteria in Lathuilière (1990). No pali. Radial symmetry dominant but hexameral arrangement difficult to ascertain, bilateral symmetry in some places, recognised by the anstomosing mode. Endotheca not observed. Columella styliform, its relief is not sufficient to be observed in every calices in distal view. Synapticule or adtrabecular bars present, wall absent.
Remarks
The peculiarity of the genus is in the mode of growth, typical for the species Thamnasteria dendroidea, the type species of Thamnasteria. Then, there is no reason to keep Dactylastrea valid. Two nominal species were attributed to Dactylastrea.
This page has been in preparation since 06-Jul-2009 09:05
This version was contributed by Bernard Lathuilière on 08-Mar-2013 17:49.
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
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