Stylosmilia trapeziformis Gregory 1900: 47, pl. 11, figs. 5-14.; Original Designation
Type Specimen: Syntype; GSI N° 6853-6862; Verified; Dry Preserved
Type Locality: Coral Bed of the Jhurio Formation (Middle Bathonian), Jumara Dome, Kachchh, India
Kachchh material has been described and illustrated by Pandey and Fürsich (1993: 12, pl. 1, figs. 4, 9, Text-fig. 9). The genus has also been described and illustrated by Alloiteau (1958: 68-69, pl. 16, figs. 10-11, pl. 22, figs. 1-2, pl. 30, fig. 2) and Bendukidze (1982: 79, pl. 28, fig. 2.
Corallum phaceloid. Corallites formed by intracalicular budding. Corallites dichotomizing, very small in diameter, elongate, cylindrical or subprismatic in shape, angular, trigonal, quadrangular, hexagonal, or elliptical in cross-section. Corallite wall septo-parathecal with thin epitheca. Corallites occasionally connected by cross tubules. Columella feeble or absent. Septa laminar, usually arranged in less than three cycles with irregularly developed auriculae at the inner edge which may join to form columella. Endotheca thin and tabular
Stylosmilia Milne-Edwards and Haime (1848: 274; 1850: xxvii; Wells 1956) is the closest comparable genus. The subprismatic corallites with apophyses in Lochmaeosmilia differentiates it from Stylosmilia.
Wells (1943, 1956: F398) defined the genus Lochmaeosmilia on the basis of Stylosmilia trapeziformis Gregory 1900, which he designated as type species. Alloiteau (1958: 68) found that Eunomia radiata Lamouroux (1821: 83, pl. 81, figs. 10-11) and Stylosmilia trapeziformis are members of the same genus, as both of them exhibit similar morphological characters, and erroneously declared E. radiata as the type species of Lochmaeosmilia. Wells (1943: 48) interpreted the figures of Stylosmilia trapeziformis given by Gregory (1900: pl. 11, figs. 5-12) as showing extracalicular budding and an epithecal wall, despite Gregory's (1900: 47) description of intracalicular budding. In the type specimen (as seen in other topotypes) there are clear indications of intracalicular budding). Wells (1943, 1956), Alloiteau (1958) and Bendukidze (1982) assigned Lochmaeosmilia to the family Amphiastreidae Ogilvie 1897. The members of this family are characterized by a distinct epitheca, by the lack of a columella (its place being occupied by one large septum projecting into the axial space). Many of the Kachchh specimens show auriculae along the inner edges of the septa which eventually fuse together and give the appearance of a columella. Specimens illustrated by Gregory (1900) also show a columella. However, Gregory (1900: 47) mentioned that the columella is "not very prominent; variable in size in cross sections of corallites". This character, together with the septo-parathecal wall and endothecal elements, refers L. trapeziformis Gregory to the family Stylinidae to which Gregory originally had assigned the species. Wells (1956: F398) also mentioned Lochmaeosmilia belonging possibly to the Stylinidae.
From Coral Bed (Jhurio Formation), Jumara Dome (Middle Bathonian) of the Kachchh Basin (India), Mughanniyya Formation (Callovian) east of Deir-Alla and Hamam Formation (Bathonian) of Tal el Dhahab (Jordan), Bathonian (Madagascar), Jurassic (Ethiopia).
- Subsaharan Africa; Middle Jurassic
- Central Asia; Middle Jurassic
- South Asia; Middle Jurassic
This page has been in preparation since 15-May-2009 17:03
This version was contributed by Bernard Lathuilière on 14-Mar-2013 10:41.
Page authors are: Dhirendra Kumar Pandey. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Bernard Lathuilière