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North American Recent Soft-shelled Turtles (Family Trionychidae) Part 8

North American Recent Soft-shelled Turtles (Family Trionychidae) - LightNovelsOnl.com

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_Records in the literature._--FLORIDA: _Alachua_: 10 mi. ENE Gainesville (Schwartz, 1956:18). _Brevard_: Merritt Island (Neill, 1958:6). _Broward_: Fort Lauderdale (Schwartz, _op. cit._:19). _Charlotte_: (Carr, 1940:107). _Clay_: Green Cove Springs (Brimley, 1910:18); St. John's River (Crenshaw and Hopkins, 1955:21); Doctor's Inlet (Schwartz, _op. cit._:18). _Collier_: Royal Palm Hammock (Crenshaw and Hopkins, _op. cit._:20); 11.2 mi. E Monroe Station (Schwartz, _op. cit._: 19). _Columbia_: (Carr, _loc. cit._). _Dade_: Paradise Key (Schwartz, _loc. cit._); Homestead (eggs, Stejneger, 1944:43). _Duval_: 4-10 mi. S Jacksonville (Deckert, 1918:31). _Glades_: _ca._ 8 mi. SW Okeechobee State Park. _Lake_: Alexander Springs (Schwartz, _op. cit._:18). _Lee_: 18 mi.

S Fort Myers (Conant, 1930:63); 6 mi. SE Fort Myers (Hamilton, 1947:209).

_Levy_: Gulf Hammock (Schwartz, _loc. cit._); Brownson (Stejneger, _op. cit._:42).

_Monroe_ and _Okaloosa_ (Carr, _loc. cit._). _Okeechobee_: 6 mi. E Kissimmee River; state hwy. 78 "near" Okeechobee-Glades co. line. _Palm Beach_: SW part of Lake Okeechobee, near Clewiston; Milton Island Cove (Schwartz, _loc. cit._).

_Pasco_: mouth Pithlachascotee River (Neill, _op. cit._:26). _Pinellas_: Belleair (Brimley, _loc. cit._); Seminole (Conant, _loc. cit._); 5 mi. E Clearwater (Schwartz, _op. cit._:19); Gulf Port (Stejneger, _op. cit._:43). _Polk_: Lake s.h.i.+pp, near Winter Haven (Telford, 1952:185). _Sarasota_: 15 mi. E Sarasota (Conant, _loc. cit._); Venice (Conant, _op. cit._:61). _Taylor_: "near" Foley. _Wakulla_: "near" Crawfordville (Crenshaw and Hopkins, _op. cit._:15).

GEORGIA: _Baker_: 5 mi. NW Newton, 5 mi. W Newton, 4 mi. N Newton.

_Ben Hill_: 6 mi. E Fitzgerald (Crenshaw and Hopkins, 1955:15). _Bulloch_: 14 mi. SE Statesboro (Schwartz, 1956:19). _Decatur_: "near" Bainbridge (Crenshaw and Hopkins, _loc. cit._). _Emanuel_: "near" Midville. _Evans_: 8 mi. NE Mana.s.sas, Tattnall County. _Ware_: Laura Walker State Park (Schwartz, _loc.

cit._). _Wilc.o.x_: 3 mi. SE Forest Glen (Crenshaw and Hopkins, _op. cit._:19).

SOUTH CAROLINA: _Beaufort_: 7 mi. NE Gardens Corner (Schwartz, 1956:19).

_Chatham_: Savannah River at Savannah (Schwartz, _op. cit._:8-9). _Colleton_: 5 mi. from Whitehall, Combahee River (Schwartz, _op. cit._:19).

=Trionyx spinifer= Lesueur

Spiny Softsh.e.l.l

_Range._--In Canada, southern Ontario and Quebec; in the United States, northwestern Vermont and western New York south to northern Florida, east to central Montana, eastern Wyoming and Colorado, and New Mexico; introduced into the Colorado River system of California, Nevada, Arizona and New Mexico; in Mexico, the northern part of the states of Tamaulipas, Nuevo Leon, Coahuila, and eastern Chihuahua (see map, Fig. 19).

_Diagnosis._--Juvenal pattern uniform tan or brownish lacking markings, having whitish dots or spots, or having well-defined, blackish ocelli or spots; surface of carapace "sandpapery" in adult males; conical projections (in some subspecies) along anterior edge of carapace in large females; contrasting pattern of blackish marks on pale background (in some subspecies) on dorsal surface of limbs of adult males.

Opisthotic-exoccipital spur well-developed; epiplastral callosity, when present, not covering entire surface.

_Description._--Septal ridges present; external and proportional characteristics variable (see accounts of subspecies); range in length of plastron (cm.) of ten largest specimens of each s.e.x (mean follows extremes), males, 13.8-16.0, 14.4; females, 26.0-31.0, 28.0.

[Ill.u.s.tration: FIG. 19. Geographic distribution of _Trionyx spinifer_.

Guide to subspecies:

1. _T. s. spinifer_ 2. _T. s. hartwegi_ 3. _T. s. asper_ 4. _T. s. pallidus_ 5. _T. s. guadalupensis_ 6. _T. s. emoryi_ ]

Greatest width of skull usually at level of squamosal (74%); foramen magnum rhomboidal; ventral surface of supraoccipital spine narrow proximally, usually having medial ridge; opisthotic-exoccipital spur well-developed (66%); distal part of opisthotic wing tapered, not visible in dorsal view; lateral condyle of articular surface of quadrate larger than medial articular surface, not tapered posteriorly; maxillaries in contact above premaxillaries (88%); usually a combination of seven neurals, seven pairs of pleurals and contact of seventh pair of pleurals (83%); angle of epiplastron approximately 90 degrees; callosities when present on epiplastron not covering entire surface; hyo-hypoplastral suture usually present.

_Comparisons._--_Trionyx spinifer_ can be distinguished from _T.

ferox_ and _T. muticus_ by the presence of any one of the characters mentioned in the "Diagnosis." Both s.e.xes and all sizes of _T.

spinifer_ resemble _ferox_ but differ from _muticus_ in having septal ridges. Most individuals of _T. spinifer_ (except some large females) resemble _muticus_ but differ from _ferox_ and large females of _ater_ in having a pale outer rim that is separated from the ground color of the carapace by a distinct (_spinifer_) or dusky (_muticus_) dark line. Large females of the subspecies _spinifer_, _hartwegi_, _asper_ and _pallidus_ may have enlarged conical projections along the anterior edge of the carapace and, unless these projections are considerably worn, are readily distinguished from large females of _ferox_ (flattened, k.n.o.blike prominences), and _muticus_ and _ater_ (smooth surface, no prominences). Large females of the subspecies _guadalupensis_ and _emoryi_ resemble _muticus_ and _ater_, and to some extent _ferox_, in having low, scarcely elevated prominences along the anterior edge of the carapace. Some females of _emoryi_ resemble _ferox_ in that the plastron extends farther forward than the carapace.

_T. spinifer_ is intermediate in size between _ferox_ (larger) and _muticus_ (smaller); the maximum size of the plastron in adult males is approximately 16.0 centimeters (14.0, _muticus_; 26.0, _ferox_), and of females, 31.0 centimeters (21.5, _muticus_; 32.5, _ferox_). The head for all subspecies of _spinifer_ is proportionately narrower than in _ferox_ but wider than in _muticus_.

In the skull, _spinifer_ more closely resembles _ferox_ than _muticus_, but differs from both _ferox_ and _muticus_ in usually having a well-developed opisthotic-exoccipital spur. Skulls of _spinifer_ resemble those of _muticus_ but differ from those of _ferox_ in being widest at the level of the squamosal. Skulls of _spinifer_ resemble those of _ferox_ but differ from those of _muticus_ in having the 1) ventral surface of the supraoccipital spine narrow proximally, and usually having a medial ridge, 2) foramen magnum rhomboidal, 3) distal part of opisthotic wing tapered, 4) lateral condyle of articular surface of quadrate not tapered posteriorly, and larger than medial articular surface, and 5) maxillaries in contact above premaxillaries. _T. spinifer_ resembles _ferox_ but differs from _muticus_ in having the epiplastron bent at an approximate right angle. _T. spinifer_ differs from _ferox_ in having an epiplastral callosity, and from _muticus_ in that the callosity does not cover the entire surface of the epiplastron. The hyo-hypoplastral suture is present more often in _spinifer_ and _muticus_ than in _ferox_.

_Remarks._--Gray (1869:221) proposed the generic name _Callinia_ as a new name for _Aspidonectes_ as understood by Aga.s.siz (1857:403). Gray referred _Trionyx spiciferus_ (= _spiniferus_) Lesueur to _Callinia_.

Stejneger (1907:514) designated _Trionyx spiniferus_ Lesueur as the type species of _Callinia_. If _Trionyx spiniferus_ Lesueur is considered to be generically distinct from other soft-sh.e.l.led turtles, _Callinia_ Gray, 1869, is available as a generic name with _Trionyx spiniferus_ Lesueur, 1827, as the type species by subsequent designation.

_Geographic variation._--_T. spinifer_ is the most variable and widespread species of the genus in North America. Size of ocelli on the carapace decreases from east to west on turtles inhabiting waterways of the Upper Mississippi River drainage. The most impressive gradient, geographically oriented from western Louisiana to southwestern Texas is seen in each of several features: decrease in size of tubercles on the anterior edge of the carapace, reduction in contrast of pattern on the dorsal surface of limbs and side of head, change in pattern on the dorsal surface of the snout, and increase in the size of white spots on the carapace. But the gradient in size of white spots is reversed in _T.

s. emoryi_, which has small white spots on the carapace. Some of the characters at the western terminus of this geographical gradient are shared with _T. ater_ and _muticus_. Those subspecies comprising the _emoryi_ group also show proportional characters that correspond closely with those of _T. ferox_.

On the basis of tuberculation and pattern on carapace, side of head, dorsal surface of limbs and snout, _Trionyx spinifer_ may be divided into six subspecies.

=Trionyx spinifer spinifer= Lesueur

Eastern Spiny Softsh.e.l.l

Plates 33, 34, and 52

_Trionyx spiniferus_ Lesueur, Mem. Mus. Hist. Nat. Paris, 15:258, pl. 6, December, 1827.

_T[rionyx] s[pinifer] spinifer_ Schwartz, Charleston Mus. Leaflet, No. 26:11, May, 1956.

_Trionyx ocellatus_ Lesueur, Mem. Mus. Hist. Nat. Paris, 15:261, December, 1827.

_Apalone hudsonica_ Rafinesque, Atlan. Jour., Friend Knowledge, Philadelphia, 1(No. 2, Art. 12):64, Summer, 1832.

_Trionyx annulifer_ Wied-Neuwied, Riese Nord-Amerika, 1(pt. 3):140, 1838.

_Tyrse argus_ Gray, Cat. Tort. Croc. Amphis. Brit. Mus., p. 48, 1844.

_Aspidonectes nuchalis_ Aga.s.siz, Contr. Nat. Hist. United States, 1(pt. 2):406, 1857.

_?G[ymnopus] olivaceus_ Wied-Neuwied, Nova Acta Acad.

Leopold.-Carol., 32:55, pl. 5, 1865.

_Type._--Lectotype, Museum d'Histoire Naturelle, Paris, No. 8808; large stuffed female obtained by C. A. Lesueur from the Wabash River, New Harmony, Posey County, Indiana (Pl. 52).

_Range._--Northeastern United States and extreme southeastern Canada in tributaries flowing into the Mississippi River from the east, and the St. Lawrence River drainage; extreme southern Quebec and Ontario, Canada, east through southern Great Lakes region to Wisconsin, and south through New York, western Pennsylvania and Illinois to Tennessee and western Virginia (see map, Fig. 19).

_Diagnosis._--Juvenal pattern of large, thick-bordered black ocelli, often 9-10 millimeters in diameter in center of carapace on adult males, and 2-3 millimeters in diameter on hatchlings (mean OD/PL, Michigan, .066); only one dark marginal line separating pale rim of carapace from dorsal ground color.

_Description._--Plastral length of smallest hatchling, 2.7 centimeters (UMMZ 89950, INHS 3143); of largest male, 14.5 centimeters (UMMZ 72512); of largest female, 31.0 centimeters (UMMZ 40866).

Carapace olive, having large ocelli in center but smaller ocelli or spots at sides; ocelli often interrupted; pale rim of carapace not four or five times wider posteriorly than laterally, separated from darker ground color of carapace by one dark marginal line; large females often having remnants of ocelli at sides of carapace on mottled and blotched background; pattern on snout of pale, dark-bordered stripes that unite forming acute angle in front of eyes; well-defined dark markings in subocular and postl.a.b.i.al region; pattern contrasting with ground color on side of head; postl.a.b.i.al stripe interrupted, diffuse; pale postocular stripe having blackish borders interrupted, not uniting with postl.a.b.i.al stripe; dorsal surface of soft parts of body having contrasting pattern, largest blackish marks on hind limbs; elongate tail of adult males having pale dorsolateral bands with well-defined lower blackish borders; underparts whitish, often having blackish marks, except in center of plastral area; dark marks on webbing of limbs, palms and soles; dark streaks often coincident with digits; small conical tubercles on anterior edge of carapace on adult males; conical or equilateral tubercles on anterior edge of carapace of large females; accessory k.n.o.blike tubercles in nuchal region and in middle of carapace posteriorly on large females.

Ontogenetic variation in PL/HW, mean PL/HW of specimens having plastral lengths 7.0 centimeters or less, 4.09, and exceeding 7.0 centimeters, 5.50; ontogenetic variation in CL/CW, mean CL/CW of specimens having plastral lengths 8.5 centimeters or less, 1.12, and exceeding 8.5 centimeters, 1.21; mean CL/PCW, 2.02; mean HW/SL, 1.30 (including subspecies _hartwegi_); mean CL/PL, 1.39.

_Variation._--Variant individuals include: UMMZ 72512, an adult male, having some ocelli seven millimeters in diameter that are almost solid spots; UMMZ 89659 having postocular and postl.a.b.i.al stripes connected on right side of head; UMMZ 95615, 52948, 54402 having inner dark borders of pale stripes on snout represented by short dashes and dots (a ragged line connecting anterior margins of orbits on 54402); UMMZ 52948, 89659 having interrupted, black marginal lines on carapace with ends of some segments oriented inward and overlapping portion of adjacent segments; UMMZ 81699, female having plastral length of 19.0 centimeters, lacking conspicuous tubercles on anterior edge of carapace; UI 2403, CNHM 92204 having extensive dark mottling and marbling on throat and neck, undersurface of limbs and posterior portion of carapace.

_Comparisons._--_T. s. spinifer_ can be distinguished from all other subspecies of _T. spinifer_ by the presence of large black ocelli (diameter 9-10 mm. on adult males, 2-3 mm. on hatchlings) in combination with only one dark marginal line. _T. s. spinifer_ resembles _asper_ in having ocelli or dots on the carapace but differs from _asper_ in having only one dark marginal line and larger ocelli.

_T. s. spinifer_ differs from _hartwegi_ only in the large size of the ocelli. _T. s. spinifer_ resembles _hartwegi_ and _asper_ but differs from _pallidus_, _guadalupensis_ and _emoryi_ in having blackish spots and ocelli on the carapace and lacking whitish dots. _T. s. spinifer_ resembles _hartwegi_, _asper_, and _pallidus_ and differs from _guadalupensis_ and _emoryi_ in having conical or k.n.o.blike tubercles on the anterior edge of the carapace on large females.

_T. s. spinifer_ differs from the subspecies _asper_, _guadalupensis_ and _emoryi_ in having a relatively narrower head, and from _emoryi_ in having a relatively wider carapace. _T. s. spinifer_ resembles _hartwegi_ and _asper_ but differs from the other subspecies in having the carapace widest at a plane approximately one-half way back on the carapace. The subspecies _spinifer_ and _hartwegi_ have longer snouts than _pallidus_, _guadalupensis_, and _emoryi_. _T. s. spinifer_ differs from _asper_ but resembles all the other subspecies in having a relatively longer plastron.

_Remarks._--Lesueur's description of _Trionyx spiniferus_ (1827:258-261, Pl. 6) seems to be based mostly, if not entirely, on a large female (length of carapace, 13 inches), which was "Le plus grand des individus observes ..." (_op. cit._:258); an accompanying ill.u.s.tration depicting the dorsal surface of the bony carapace is unusual in lacking neurals (Pl. 6, E). Dumeril and Bibron (1835:481) mentioned eight or nine additional specimens that Lesueur sent to the Museum of Natural History in Paris. Dr. Jean Guibe informed me under letter dated September 24, 1959, that a larger stuffed female, bearing catalog number 8808 is regarded as the holotype, and that there are seven additional specimens (1949, 4143, 8807, 8809-12) in the museum at Paris. All turtles were obtained by Lesueur from the Wabash River.

To my knowledge no specimen that was available to Lesueur has been specifically designated as a type. Because the description seems to be based on one specimen, undoubtedly No. 8808, this specimen has been regarded as the holotype. However, Lesueur referred to several specimens and did not mention a type in the original description; consequently I prefer to regard No. 8808 as a lectotype.

Lesueur also described _Trionyx ocellatus_ (_op. cit._:261-263) as a variety of _T. spiniferus_ having ocelli, or parts thereof, on the carapace and mentioned three specimens. The total number of specimens that were available to Lesueur is unknown. One young alcoholic specimen having ocelli is in the British Museum (Natural History) (Gray, 1855:69). The same letter from Dr. Guibe stated that a specimen in the Museum of Natural History, Paris, No. 6957, having a carapace 17 centimeters in length, conforms to the characters of _ocellatus_ as mentioned by Lesueur, and was obtained from the Wabash River by Lesueur. Two of the specimens mentioned by Lesueur (_loc. cit._) are stated to be females. No. 6957 is an adult male and clearly shows the juvenal pattern; it is regarded as the lectotype of _T. ocellatus_ Lesueur, a name-combination, which is a synonym, based on a secondary s.e.xual difference in pattern.

Rafinesque (1832:64) described a soft-sh.e.l.led turtle from "the River Hudson between the falls of Hadley, Glen and Baker, and further up to the source" as _Apalone hudsonica_. The most outstanding characteristic was the presence of five claws on the digits of each limb. Rafinesque's recording of this characteristic was perhaps influenced by the ill.u.s.tration of a softsh.e.l.l in Bartram's _Travels_ that showed each limb with five, clawed digits. Perhaps this was the basis for Boulenger (1889:245, footnote) regarding _Apalone_ as "mythical." The large, yellowish, black-bordered spots, one behind and one in front of the eye presumably represent segments of the postocular stripe and the stripe on the snout; Rafinesque described the carapace as "entire ... the margin is yellowish unspotted, then comes a circular black line ..." and having "many round spots occulated and clouded by having a brown margin, with grey dots within." Except for five claws, the description is applicable to a softsh.e.l.l and referable to _T. s. spinifer_. To my knowledge, the only other records of the occurrence of soft-sh.e.l.led turtles in the Hudson river drainage are those of Eights (_in_ Bishop, 1923:120, Mohawk River at Cohoes), and DeKay (1842:7, Mohawk River and Hudson River near Albany); presumably these records are the basis for the comments of Holbrook (_in_ Bishop, _loc. cit._), and symbolized as an isolated locality by Conant (1958:318, map 35). The type locality of _Apalone hudsonica_ is herein restricted to the Hudson River, near Baker's Falls, Saratoga County, New York.

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