New fossil ictalurid species
Posted: 03 May 2012, 14:23
A Late Miocene Channel Catfish (Siluriformes, Ictaluridae, Ictalurus) from
the St. Marys Formation, Calvert Cliffs, Maryland, USA
John G. Lundberg and Kyle R. Luckenbill.
Notula Naturae, No.485, May 2,2012, 32 pages.
ABSTRACT.—Fossil remains of a catfish from the Late Miocene St. Marys Formation, Maryland, are described as a new,
extinct species of Ictalurus (Ictaluridae). The holotype of †Ictalurus countermani n. sp., is a three-dimensional partial skull,
Weberian complex, pectoral girdle and fin spine. Referred paratype specimens include isolated mesethmoid, premaxilla,
dorsal-fin spine and cleithrum. †Ictalurus countermani n. sp., is distinguished among congeneric species by a combination
of features of the sphenotic, cleithrum and pectoral-fin spine. The new species extends the known native geographic range of
Ictalurus onto the mid-Atlantic slope and indicates extirpation of the genus from that region before the recent transplantation
of the channel (I. punctatus) and blue (I. furcatus) catfishes. Fossils of gar (Lepisosteus) and bowfin (Amia) associated with
†I. countermani corroborate the likely freshwater environment at or near the site of their burial. An additional catfish fin spine
collected with the foregoing is identified as an ariid sea catfish, cf. Ariopsis felis.
the St. Marys Formation, Calvert Cliffs, Maryland, USA
John G. Lundberg and Kyle R. Luckenbill.
Notula Naturae, No.485, May 2,2012, 32 pages.
ABSTRACT.—Fossil remains of a catfish from the Late Miocene St. Marys Formation, Maryland, are described as a new,
extinct species of Ictalurus (Ictaluridae). The holotype of †Ictalurus countermani n. sp., is a three-dimensional partial skull,
Weberian complex, pectoral girdle and fin spine. Referred paratype specimens include isolated mesethmoid, premaxilla,
dorsal-fin spine and cleithrum. †Ictalurus countermani n. sp., is distinguished among congeneric species by a combination
of features of the sphenotic, cleithrum and pectoral-fin spine. The new species extends the known native geographic range of
Ictalurus onto the mid-Atlantic slope and indicates extirpation of the genus from that region before the recent transplantation
of the channel (I. punctatus) and blue (I. furcatus) catfishes. Fossils of gar (Lepisosteus) and bowfin (Amia) associated with
†I. countermani corroborate the likely freshwater environment at or near the site of their burial. An additional catfish fin spine
collected with the foregoing is identified as an ariid sea catfish, cf. Ariopsis felis.
