Research history s of
Otodus appendiculatus (Fig. 1-25) and
holotype of
C. lata (Fig. 26) in the third volume of
Recherches sur les poissons fossiles; the tooth in Fig. 10 is the sole
lectotype of
C. appendiculata|left|upright=1.2
Cretalamna was first described by
Swiss naturalist
Louis Agassiz using five teeth previously identified as the
common smooth-hound and collected by English paleontologist
Gideon Mantell from the
Southerham Grey Pit near
Lewes,
East Sussex. In his 1835 publication
Rapport sur les poissons fossiles découverts en Angleterre, he reidentified them as a new species of
porbeagle shark under the taxon
Lamna appendiculata. The species would later be found in 1958 by Soviet paleontologist Leonid Glickman to belong to a distinct new genus-
Cretalamna. Despite Agassiz's remarks on variability, promoted into a subspecies in 1977 by Belgian paleontologist Jaques Herman, and finally elevated to the species level as
Cretolamna lata by Herman and paleontologist Van Waes Hilde in 2012. In 1897, French paleontologist Fernand Priem described a single tooth from the Köpinge Sandstone in
Scania,
Sweden under the taxon
Lamna borealis. This would be revised to '' 'Cretolamna borealis'
by Glickman in a 1980 paper. In 1935, French Paleontologist Camille Arambourg described a new subspecies of C. biauriculata
from teeth found in Moroccan phosphates under the taxon Lamna biauriculata maroccana
, which was elevated into its own species in 1997. In 1972, French ichthyologist Henri Cappetta described teeth from Maastrichtian deposits near the Mentès well in Tahoua, Niger, which he assigned to the subspecies Lamna biauriculata nigeriana
. This subspecies would also be elevated to its own species in 1991. In 1975, Cappetta and American paleontologist Gerard Case examined Cretalamna
teeth described by Arambourg in 1952 from Danian deposits in Morocco and proposed that it represents a new subspecies of the type species and assigned it the taxon Cretolamna appendiculata arambourgi
, which Siversson et al.'' (2015) elevated into its own species.
Etymology The genus
Cretalamna is a portmanteau of
creta, the Latin word for "chalk", prefixed to the genus
Lamna, which is a
romanization of the Ancient Greek λάμνα (lámna, meaning "kind of fierce shark"). When put together they mean "chalk-shark", which refers to chalk deposits from which the species' type specimens were found in.
C. biauriculata's specific epithet is a portmanteau derived from the Latin prefix
bi- (two) prefixed onto the Latin
auriculātā (eared), together meaning "having two ears". This is a reference to the species' large lateral cusplets, which somewhat resemble a pair of ears. Since then, the reinstatement of '' 'Cretalamna'
gained prominence and by the 2010s, was accepted by the majority of paleontologists. However, some paleontologists including Cappetta strongly opposed it. In an attempt to suppress the usage of 'Cretalamna'
, Cappetta appealed to a representative of the ICZN, arguing that the original intentions of Glickman and the prevailing usage of 'Cretolamna' '' prior to Siversson (1999) secures its priority. The ICZN, who reportedly were impressed by Cappetta's "spirit", subsequently erected Article 33.3.1 of the 2000 Edition of the Code in order to address this situation in the future, which states that "when an unjustified emendation is in prevailing usage and is attributed to the original author and date it is deemed to be a justified emendation". While Cappetta argued in a 2012 handbook that this new provision justifies the priority of '' 'Cretolamna' '' due to the spelling's overwhelmingly prevailing usage prior to its replacement by Siversson in 1999, Siversson himself pointed out in a 2015 paper that the provision cannot be worked retroactively, and that the continued prevailing usage of '' 'Cretalamna' '' since the provision's establishment ironically secures its priority rather than threaten it. '' 'Cretalamna'
currently remains as the most prevalent spelling and paleontologists have expressed the unlikeliness of a return to the usage of 'Cretolamna' ''. ==Description==