Ecphora (genus)

Ecphora
Temporal range: Langhian–Piacenzian
An apertural view of a shell of Ecphora gardnerae gardnerae, drawn by J. C. McConnell[1]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Caenogastropoda
Order: Neogastropoda
Family: Muricidae
Subfamily: Ocenebrinae
Genus: †Ecphora
Conrad, 1843 [1]

Ecphora is a genus of extinct predatory ocenebrinid murexes indigenous to the North American Eastern Seaboard from Miocene until their extinction during the Pliocene. The common name for this genus and a group of related genera is "ecphora"(s).

Etymology

The name "Ecphora" is Greek, meaning "bearing out." The word was originally used by Vitruvius to signify the projecture of a member or moulding of a column, and here refers to the distinctive "T-shaped" ribs that project from the shell.[2]

Subdivisions

As originally proposed by Petuch in 1988, Trisecphora was regarded as a subgenus of Ecphora (sensu stricto), as was the genus Latecphora. However, further study (by Petuch) of these two subgenera lead to their promotion to genera proper. However, Planecphora Petuch 2004 was originally proposed as a full genus, but was then demoted to subgenus.

Currently, Ecphora is subdivided into the subgenus Planecphora, and several species complexes. Originally, the species of Planecphora consisted of the "Ecphora choptankensis Species Complex" before Petuch elevated the complex to genus status.

Subgenus Planecphora

Ecphora (sensu stricto)

fossil snail Ecphora gardnerae
Ecphora gardnerae fossil

Ecphora gardnerae Species Complex

Ecphora meganae Species Complex

Ecphora rikeri Species Complex

Ecphora quadricostata Species Complex

Evolution

Ecphora is derived from the slightly older Trisecphora, diverging during the Langhian epoch. The oldest species is E. wardi, found in the Plum Point Member of the Calvert Formation. Later during the Miocene, daughter genera, in the form of Latecphora, and Globecphora, and Planecphora split off during the early Pliocene, persisting in a coral atoll in what is now the Everglades until the late Piacenzian epoch of the late Pliocene, when remaining species of both Ecphora and Planecphora were driven to extinction due to encroachment by new murexes invading from the south.

References

  1. ^ Clark, Shattuck & Dall, The Miocene Deposits of Maryland, Maryland Geological Survey (1904), Pl. LII no. 1 as "Ecphora quadricostata".
  2. ^ Oxford English Dictionary, "Ecphora" entry.
  • Nomenclator Zoologicus info
  • G. C. Martin. 1904. Gastropoda. Maryland Geological Survey Miocene(Text):131-269
  • N. F. Sohl. 1964. Neogastropoda, Opisthobranchia, and Basommatophora from the Ripley, Owl Creek, and Prairie Bluff Formations. US Geological Survey Professional Paper 331(B):153-344
  • E. J. Petuch. 1992. New ecphoras (Gastropoda: Thaididae: Ecphorinae) from the Calvert Formation of Maryland (Langhian Miocene). The Nautilus 106(2):68-71
  • J. J. Sepkoski. 2002. A compendium of fossil marine animal genera. Bulletins of American Paleontology 363:1-560