Garden did not list a specific locality for the two specimens that he sent to London, but did mention that the turtle was common in the Savannah and Altamaha rivers (of Georgia), and rivers in east Florida. Boulenger (loc. cit.) stated that the locality of the holotype was "Georgia." Baur (1893:220) restricted the type locality to the "Savannah river, Ga." Neill (1951:17), who believed T. ferox to be absent from the Savannah River, changed the type locality of ferox to east Florida. Schwartz (1956:8) reappraised the status of softshells in Georgia and Florida and reëstablished the Savannah River (at Savannah), Georgia, as the type locality of T. ferox.
Pennant failed to use binomial nomenclature when he published the type description of Garden. The first name-combination (Testudo ferox) was proposed by Schneider (1783:220).
Lacépède (1788:137, Pl. 7) referred to Garden's description in Pennant only as "The Molle" but on a folded paper chart entitled "Table Méthodique des Quadrupèdes ovipares," which is inserted after an introduction of 17 pages, listed T. mollis; this name is again listed on another folded chart, entitled "Synopsis methodica Quadrupedum oviparorum," which is inserted between pages 618 and 619 under the genus Testudo. The illustration (Pl. 7) was taken from Pennant (Duméril and Bibron, loc. cit.). The type locality has been designated "(following Stejneger, 1944) as eastern Florida" by Schmidt (1953:108).
Bartram failed to use a binomial name with his description of "the great soft shelled tortoise," which appeared in his Travels (1791:177-179, Pl. 4 and unnumbered plate between pages 282 and 283) and two editions of a French translation (1799 and 1801, 1:307); see Harper (1940). Recently, Bartram's Travels has been placed on the Official Index of Rejected and Invalid Works in Zoological Nomenclature, Opinion 447 (see Hemming, 1957). Bartram's description of a soft-shelled turtle has provided the basis for the proposal of at least three name-combinations. The first was Testudo (ferox?) verrucosa proposed in 1795 by Schoepff; it appeared simultaneously in The Historia Testudinum and in a German translation, Naturgeschichte der Schildkröten (see Mittleman, 1944:245). Stejneger (1944:26) listed the type locality as eastern Florida. Daudin (1801:74), also referring to Bartram's description in his Voyage (French translation), proposed the name Testudo bartrami; Harper (op. cit.:717) restricted the type locality of T. bartrami from "Halfway pond," east Florida, to southwestern Putnam County between Palatka and Gainesville, Florida. Rafinesque (1832:64-65), relying on the authenticity of the illustrations in Bartram's Travels that depict a soft-shelled turtle having five claws on each of the hind feet, tubercles on the sides of the head and neck, and ten scales in the middle of the carapace (presumably inaccuracies or a composite on the part of the artist), referred to Bartram's description as a new genus, Mesodeca bartrami, a name which Boulenger (1889:245, footnote) referred to as "mythical." Geoffroy (1809a:18-19) considered Bartram's description the basis for the recognition of a second species of Chelys (binomial nomenclature not employed), and Duméril and Bibron (loc. cit.) suggested that the description was based partly on a "Chelyde Matamata." [484] The descriptive comments of Bartram are not clearly applicable to Testudo ferox Schneider; Trionyx ferox, however, is the only species of soft-shelled turtle known to occur in the region of Bartram's observations (east Florida), and the type locality was restricted to Putnam County, Florida, by Harper. The name-combinations, Testudo (ferox?) verrucosa Schoepff, Testudo bartrami Daudin, and Mesodeca bartrami Rafinesque are junior synonyms of Testudo ferox Schneider.
Schweigger (1812:285) referred ferox to the genus Trionyx following the description of that genus by Geoffroy in 1809. Testudo ferox was listed as a synonym by Geoffroy in the description of Trionyx georgicus (1809a:17); Duméril and Bibron (1835:432) mentioned that the specific characters of georgicus were taken from Pennant. The name Trionyx georgianus presumably appears for this taxon in Geoffroy's earlier-published synopsis (1809:367). T. georgicus was listed as occurring in rivers of Georgia and the Carolinas; the type locality was restricted by Schmidt (op. cit.:109) to the Savannah River, Georgia. The two specific names georgicus and georgianus are regarded as substitute names and junior synonyms of T. ferox.
Geoffroy (1809a:14-15) also described Trionyx carinatus, a name-combination that hitherto has been considered a synonym of Trionyx ferox. There is no indication from the description that carinatus is applicable to ferox. Most comments pertain to a description of the bony carapace and plastron, which Geoffroy depicts in Plate 4. It is a young specimen judging from the small and isolated preneural; the seventh pair of pleurals is unusual in being fused (no middorsal suture), and the neurals seem large in proportion to the size of the pleurals. The anterior border of the carapace is described as having tubercles. Geoffroy listed Testudo membranacea and Testudo rostrata as synonyms of carinatus. Fitzinger (1835:127) listed T. membranacea, T. rostrata and T. carinatus as synonyms of Trionyx javanicus (= T. cartilagineus), which was also described by Geoffroy (op. cit.:15). Duméril and Bibron (op. cit.:478, 482) considered carinatus to be the young of spinifer (ferox as synonym). Gray (1844:48), however, referred T. membranacea and T. rostrata to the synonymy of T. javanicus, but considered T. carinatus to be a synonym of T. ferox (op. cit.:50), an interpretation followed by all subsequent authors. Trionyx carinatus is questionably listed as a synonym of ferox by Stejneger (1944:27). Duméril and Bibron (op. cit.:482) wrote that the young type of carinatus is in the museum at Paris. Dr. Jean Guibé informs me in letter of September 24, 1959, that the type of Geoffroy's T. carinatus cannot be found in the Natural History Museum at Paris. For the present, T. carinatus is considered a nomen dubium. According to Stejneger (1944:27), Trionyx brongniarti Schweigger is a substitute name for T. carinatus.
I am unable to add anything to Stejneger's (op. cit.:32) account of Trionyx harlani; the mention of its occurrence in east Florida indicates that it is indistinguishable from Testudo ferox Schneider.
T. ferox was considered to be indistinguishable from Lesueur's Trionyx spiniferus (described in 1827), until Agassiz (1857:401) pointed out the differences between the two species. However, Agassiz (op. cit.:402, Pl. 6, Fig. 3) regarded juveniles of T. spinifer asper as the young of ferox. Consequently, the geographic range of ferox, as envisioned by Agassiz, extended from Georgia and Florida west to Louisiana. Neill (1951:15) considered all [485] American forms conspecific. Crenshaw and Hopkins (1955) and Schwartz (1956) demonstrated that ferox is a distinct species.
Fitzinger (1843:30) designated the species ferox as the type species of his genus Platypeltis as follows: "Platypeltis. Fitz. Am[erica]. Platypelt. ferox. Fitz. Typus." If populations of soft-shelled turtles that are referable to Testudo ferox Schneider are considered to comprise a distinct genus by future workers, Platypeltis Fitzinger, 1835, is available as a generic name with Testudo ferox Schneider, 1783, as the type species (by subsequent designation).
Trionyx ferox in the northern part of its range is sympatric with T. spinifer asper. In the region of overlap, the two species are nearly always ecologically isolated; ferox inhabits lentic waters, whereas T. s. asper is partial to lotic waters (Crenshaw and Hopkins, op. cit.:16). There is no evidence of intergradation or hybridization.