Chomatoseris
Thomas, 1935, p. 429
Type Species
Madrepora porpites Smith 1816, p. 30, pl. upper Oolite fig. 4 (non Madrepora porpita Fougt in Linnaeus); Original Designation
Type Specimen: Unknown; ?; Not Traced; Unknown
Type Locality: Great oolite, Broadfield farm, Gloucestershire
Classification
Description
Solitary cyclolitoid corallum. No epitheca, no wall. Thin numerous radial elements, pennular and regularly fenestrate. Discontinuous menianae. The finely dentate pennular rims are directed toward the distal direction i.e. upward on the upper surface and downward on the lower surface of the adult stage. This means that the growth is centrifugal at the adult stage and suggests an aptation for mobility. Septa are straight but often anastomosed in a contratingent manner. Hexameral symmetry difficult to decipher and bilateral symmetry marked by the elongate axial pit in some species. In depth, inner edges of septa are anastomosted in the axial zone. Synapticule are numerous and rather uniformly distributed. Vesicular dissepiments present.
Comparisons
Other solitary microsolenid like Trocharaea or Trochoplegma do not grow downward. Genabacia is colonial.
Remarks
G. Gill investigated very thoroughly Chomatoseris in many aspects (morphology, structure, ecology, biogeography, teratology, variability) and the genus was the basis for the description of pennules. (Gill et al., 1978; Gill, 1967; Gill, 1968; Gill, 1970; Gill and Semenoff-Tian-Chansky, 1971; Gill, 1977; Gill and Coates, 1977; Gill and Lafuste, 1971). Unfortunately the taxonomy of the species included in the genus is still not satisfying. 21 nominal species are cited in this genus or in Anabacia. Some are not Chomatoseris (forms with epitheca or wall, without downward growth). Then the distribution is questionnable for several occurrences.
Distribution
- Western Europe, Central Europe, Eastern Europe, North Africa, Subsaharan Africa, Central Asia, East Asia, South America; Early Jurassic - Middle Jurassic
This page has been in preparation since 07-May-2009 09:56
This version was contributed by Bernard Lathuilière on 06-Oct-2009 08:14.
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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