Cambarus distans Rhoades 1944

Cambarus (Jugicambarus) distans Rhoades

Cambarus distans Rhoades, 1944a: 136, fig. 9a–f.

Cambarus (Jugicambarus) distans.—Hobbs, 1969b: 107, figs. 9, 19e.

TYPES.—Holotype, allotype, and “morphotype,” USNM 81327, 81329, 81328 (I, , II); paratypes, CM, USNM, RR.

TYPE-LOCALITY.—“Cumberland River and small tributary, just above Cumberland Falls, McCreary County, Kentucky” (Rhoades, 1944a: 139).

RANGE.—Cumberland drainage in southeastern Kentucky and tributaries on Cumberland Plateau in Tennessee.

HABITAT.—Streams.

Cambarus (Jugicambarus) distans Rhoades

Cambarus distans Rhoades, 1944:136–139, 141, fig. 9a–f.

Cambarus diistans.—Rhoades, 1944:139 [erroneous spelling].

Cambarus (Jugicambarus) distans.—Hobbs, 1969a:107, 108, 142, figs. 9, 19e; 1972b:123, 146, figs. 106a, 107d: 1974b: 18, fig. 53.—Bouchard, 1976a:573–575; 1976b:585–587, 589, 593.

The above list of references is not a complete bibliography of the species but includes all synonyms, and references to illustrations and to summary articles. No previous records of its occurrence in Georgia have been recorded.

DIAGNOSIS.—Body pigmented, eyes well developed. Rostrum with margins somewhat thickened and lacking marginal spines or tubercles. Areola 4.3 (in juveniles) to 5.7 (rarely) times as long as wide and comprising 33.9 (in juveniles) to 37.3 percent of entire length of carapace (40.0 to 44.1 percent of postorbital carapace length), and bearing 2 to 4 punctations across narrowest part. Cervical spine represented by small tubercle, latter sometimes flanked by 1 or 2 additional ones. Suborbital angle obtuse (sometimes acute in juveniles). Postorbital ridge ending cephalically in rounded, elevated terminus but lacking distinct tubercle. Antennal scale 2.0 to 2.5 times as long as broad, broadest at or slightly distal to midlength. Chela with single row of 7 to 9 (usually 7) tubercles along mesial margin of palm; distolateral margin of palm weakly costate; both fingers with well-defined longitudinal ridges dorsally. First pleopod of first form male with long distally notched central projection bent at approximately 120 degrees to shaft of appendage, its tip not reaching level proximal to distal base of mesial process; mesial process somewhat inflated, tapering to weakly emarginate tip directed caudoproximally and somewhat laterally at angle of about 120 degrees to main shaft of appendage and reaching caudally as far as central projection. Female with annulus ventralis comparatively symmetrical; central depression broad with tilted S-shaped sinus originating on dextral side of depression and ending on caudal wall of annulus near median line; first pleopod present.

COLOR NOTES (Figure 70d).—Carapace olive tan with gray brown transverse band immediately cephalic to cervical groove and along posterior flank of reticulate mandibular adductor region; similarly colored line coursing along lateral margin of postorbital ridge. Dark rostral ridges flanked by pale tan to cream; hepatic and cervical tubercles also tan to cream. Thoracic region with irregular gray brown horns of saddle, bar totally lacking; branchiostegal region below horns mottled. Abdomen with paired dorsolateral linear series of maculations on anterior part of first through fifth abdominal segments, spots decreasing in size caudally, those on first segment joined by narrow transverse band along caudal margin; bases of pleura with broad V-shaped markings on second through fifth segments, markings on first and sixth segments more nearly straight. Telson with cephalic section and marginal area of caudal section mottled. Uropods with lateral halves of both rami distinctly mottled, mesial halves less so. Chela olive tan dorsally with dark band on proximal side of ridge on propodus opposite base of dactyl and along lateral costa; tips of fingers and tubercles on palm orange tan; tubercles on opposable margins of fingers almost cream. Carpus and distal part of merus olive tan with dark markings and pale tubercles. Peduncles of antennule and antenna mottled, flagella banded almost black on pale tan. Antennal scale mostly pale but with lateral margin and distolateral spine dark. Remaining pereiopods greenish dorsally from distal part of ischium to dactyl, joints flanked proximally by orange tan markings. Venter and third maxillipeds pinkish cream.

TYPES.—Holotype, allotype, and “morphotype,” USNM 81327, 81329, 81328 (I, , II); paratypes, CM, USNM, RR.

TYPE-LOCALITY.—“Cumberland River and small tributary, just above Cumberland Falls, McCreary County, Kentucky.”

RANGE.—According to Bouchard (1976b:593), this crayfish occurs in the Kentucky, Cumberland, and Tennessee river drainages in Kentucky and Tennessee southward to the Emory drainage. He also reported it from Town and South Sauty creeks on Sand Mountain in Alabama. The new localities cited below for Georgia are also situated on Sand Mountain in the Appalachian Plateau Province sector of the Tennessee River basin.

GEORGIA SPECIMENS EXAMINED.—I have examined a total of 17 specimens from the following localities. Dade County: (1) Murphy Hollow Creek about 1 mi S of Interstate Hwy 24 on Murphy Hollow Creek Rd, 3j, 2j. 23 Apr 1968, E. T. Hall, Jr., HHH, collectors; (2) spring run trib to Murphy Hollow Creek, 2.1 mi S of Interstate Hwy 24 on Murphy Hollow Creek Rd, 6II, 2, 1j, 3j, 24 Oct 1975, T. A. English, Jr., HHH. (See “Life History Notes.”)

VARIATIONS.—All of the specimens known from Georgia were collected in the two nearby localities on Murphy Hollow Creek, and few differences worthy of note have been observed among them. The most obvious involves the number of tubercles along the mesial margin of the palm of the chela that, as pointed out in the “Diagnosis,” ranges from seven to nine (the maximum illustrated in Figure 78j). The antennal scale is also variable in shape, the distomesial margin strongly inclined as in Figure 78i or almost transverse.

A comparison of the Georgia specimens with the primary types alone would convince one that the specimens from Sand Ridge are far from being typical of Cambarus (J.) distans (see the illustrations cited in Rhoades, 1944, fig. 9a–f, and Hobbs, 1974b, fig. 53). The first pleopod of the male differs strikingly in that the central projection of the holotype is much shorter and less strongly recurved, the mesial process of that appendage is more robust basally, less evenly tapering, and directed at about 90 degrees to the shaft of the appendage; also the rostral margins are more tapering, and the areola is more densely punctate; conspicuous differences also exist in the annuli ventrales. Because the variations that occur in the species, particularly in specimens occurring in the Tennessee drainage, have never been analyzed in detail, and because of the apparent affinity of these Georgia crayfish to the Tennessee material, the Georgia specimens are tentatively assigned to Cambarus (J.) distans, but the possibility exists that a separate taxon should be proposed to receive them.

SIZE.—The largest specimen available from Georgia is a first form male having a carapace length of 32.4 mm (postorbital carapace length, 27.9 mm). The corresponding lengths of the other first form male are 30.5 (29.3) mm.

Cambarus (Jugicambarus) distans Rhoades

Cambarus distans Rhoades, 1944a:136, fig. 9a–f.—Bouchard, 1976a:573; 1976b:585.—Hobbs, 1981:200, fig. 78.

Cambarus diistans.—Rhoades, 1944a:139 [erroneous spelling].

Cambarus (Jugicambarus) distans.—Hobbs, 1969b:107, figs. 9, 19e; 1974b:18, fig. 53.

TYPES.—Holotype, allotype, and “morphotype,” USNM 81327, 81329, 81328 (male I, female, male II); paratypes, CM, USNM, OSM.

TYPE LOCALITY.—“Cumberland River and small tributary, just above Cumberland Falls, McCreary County, Kentucky” (Rhoades, 1944a: 139).

RANGE.—Kentucky, Cumberland, and Tennessee river drainages in Kentucky and Tennessee southward to Sand Mountain in Alabama and Georgia.

HABITAT.—Streams.