Procambarus litosternum Hobbs 1947

Procambarus (O.) litosternum

E Ankylocythere ancyla: Evans (Hart and Hart, 1974:21)

Entocythere elliptica: Emanuel (Hart and Hart, 1974:88)

Procambarus (Ortmannicus) litosternum Hobbs

Procambarus litosternum Hobbs, 1947a:9, figs. 3, 4, 9, 11, 13 [not 15], 16, 19, 21, 26, 29, 30.

Procambarus (Ortmannicus) litosternum.—Hobbs, 1972a:9; 1974b:57, fig. 221; 1981:403, figs. 13d, 137e, 138g, 158–160, 250.

TYPES.—Holotype, allotype, and “morphotype,” USNM 82261 (male I, female, male II); paratypes, USNM.

TYPE LOCALITY.—Stream, 5 miles (8 km) northeast of Swainsboro on U.S. Highway 25, Emanuel County, Georgia.

RANGE.—Canoochee, Ogeechee, Newport, and Savannah river basins in southeastern Georgia.

HABITAT.—Streams.

Procambarus (Ortmannicus) lophotus Hobbs and Walton

Procambarus lophotus Hobbs and Walton, 1960:123, figs. 1–11.

Procambarus (Ortmannicus) lophotus.—Hobbs, 1972a:9; 1974b:58, fig. 245; 1981:379, figs. 2, 15d, 136c, 138h, 146, 147, 251.

TYPES.—Holotype, allotype, and morphotype, USNM 104404, 104405, 104406 (male I, female, male II); paratypes, TU, USNM.

TYPE LOCALITY.—Roadside ditch, 3.4 miles (5.4 km) northeast of Haynesville on State Route 111, Lowndes County, Alabama.

RANGE.—Alabama drainage system from Clarke County, Alabama, to Chattooga and Whitfield counties, Georgia, and the Tennessee river basin in Walker and Catoosa counties, Georgia, and Polk County, Tennessee.

HABITAT.—Lentic and lotic situations and burrows (tertiary burrower).

Procambarus (Ortmannicus) litosternum Hobbs

Procambarus litosternum Hobbs, 1947a:9, figs. 3, 4, 9, 11, 13, 16, 19, 21, 26, 29, 30.

Procambarus (Ortmannicus) litosternum.—Hobbs, 1972a:9.

TYPES.—Holotype, allotype, and “morphotype,” USNM 82261 ( I. . II); paratypes, USNM.

TYPES-LOCALITY.—Stream 5 miles northeast of Swainsboro on U.S. Highway 25, Emanuel County, Georgia.

RANGE.—Tributaries of the Canoochee, Ogeechee, and Newport rivers in Bulloch, Jenkins, Emanuel, and Liberty counties, Georgia.

HABITAT.—Streams.

Procambarus (Ortmannicus) litosternum Hobbs

Procambarus litosternum Hobbs, 1947a:4, 8–13, figs. 3, 4, 9, 11, 13, [not 15 as indicated], 16, 19, 21, 26, 29, 30; 1947b:29; 1958a:72, 78, 79, 83, 86, 90, fig. 12; 1958b:160; 1959:889; 1962:284, fig. 27; 1968b:K–10, fig. 25e.—Anonymous, 1972e:77.—Hart and Hart, 1974:21, 88.—Wharton, 1978:46, 220.

Procambarus (Ortmannicus) litosternum.—Hobbs, 1972a:9; 1972b:64, 151, 154, figs. 29b, 50b; 1974b:57, fig. 221.

These references are believed to constitute a complete bibliography of the species, and, inasmuch as this crayfish is endemic to the state, all refer to Georgia.

SUMMARY OF LITERATURE.—Accompanying the description of this crayfish by Hobbs (1947a) were notes on the type-locality, a statement of its affinities, and several locality records in the Canoochee and Ogeechee watersheds of Bulloch, Emanuel, and Jenkins counties. A key to the members of the pictus Subgroup was appended. In describing another member of the Subgroup, Procambarus lepidodactylus Hobbs (1947b), P. (O.) litosternum was included in an expanded key, and, in his analysis of the evolution of the pictus Group, Hobbs (1958a) discussed its range, certain morphological characters, and its relationships. In his key to the American crayfishes (1959), he noted that the range of the species encompassed the “Canoochee, Ogeechee, and Newport rivers in Ga.” No additional information appeared in the literature until Anonymous (1972e) questionably identified two specimens from Pendleton Creek on State Route 292, Toombs County, as members of this species. Hobbs (1972a, b), in recognizing several subgenera of the genus Procambarus, assigned this crayfish to the subgenus Ortmannicus. Hart and Hart (1974) reported the infestation of members of this species in Evans County by two entocytherid ostracods, Ankylocythere ancyla and Entocythere elliptica.

DIAGNOSIS.—Rostrum with marginal spines or tubercles, lacking median carina. Carapace with 1 pair of cervical spines. Areola 3.2 to 4.8 (average 3.8) times as long as broad and constituting 26.3 to 30.5 (average 28.5) percent of entire length of carapace (36.4 to 41.6, average 38.6 percent of postorbital carapace length). Antennal peduncle with prominent spine, occasionally reduced to acute tubercle on ischium. Lateral half of ventral surface of ischium of third maxilliped lacking conspicuous mat of long plumose setae. Basis of cheliped without mesial spine. Mesial surface of palm of chela of male with mesialmost row of tubercles consistng of 7 to 12 (usually 9). Male with simple hooks on ischia of third and fourth pereiopods, in first form male that on third overreaching basioischial articulation, that on fourth not reaching articulation and opposed by prominent protuberance on cephalodistal end of corresponding basis. First pleopods asymmetrical and reaching coxae of third pereiopods, distal fourth of shaft bearing distinct cephalic hump subjacent to base of cephalic process; subapical setae flanking mesial, cephalic, and lateral bases of cephalic process and central projection, largely obscuring both, as well as caudal and adventitious processes; mesial process subspiculiform and directed caudodistally; cephalic process, with broad base and acute apex, hooding at least basal part of central projection and extending distally as far as or farther than latter; central projection strongly sclerotized, subtriangular, and extending caudodistally subparallel to cephalic process; caudal element consisting of (1) elongate, corneous caudal process projecting caudodistally from caudomesial base of central projection, flanked mesially by (2) strongly sclerotized tumescence bearing arched cristiform adventitious process, and (3) subtruncate caudal knob extending across caudodistal end of shaft, delimited caudolaterally by deep, almost straight, groove. Female with sternum cephalic to annulus lacking tubercles and caudally projecting prominences; annulus ventralis subcampanulate in outline, with ventral surface almost plane or with broad, subtriangular, median excavation; sinus forming sigmoid curve and reaching neither cephalic nor caudal margins of annulus; postannular sclerite at least three-fourths as wide as annulus and strongly arched ventrally; first pleopod present.

COLOR NOTES (Figure 137e).—Carapace mauve gray, with cream and brown to black splotches. Cephalic section with median longitudinal pinkish tan stripe poorly delimited, interrupted by brown splotches; no conspicuous markings present except pair of black spots in posterior gastric region and pale pinkish oblique mark extending from cephalic margin of antennal region posteroventrally across posterior mandibular area. Thoracic section of carapace with median longitudinal strip even less well defined than in cephalic section; saddle reduced to 2 pairs of black spots dorsolaterally marking cephalic and caudal parts of horns; caudal ridge and flange dark brown, latter fading ventrally to match pinkish tan on ventral part of branchiostegites, which also bearing few cream spots. Terga of abdomen largely pinkish tan, with paired, reddish charcoal to black markings anteriorly, these connected by narrow transverse line, and each tergum with caudal margin black; median area of terga slightly darker than lateral parts, suggesting broad, median, longitudinal dark stripe on abdomen; pleura pinkish brown, with centrally located pinkish cream spot. Telson and uropods marked like those of P. (O.) epicyrtus although dark areas not so intense. Similarly, antennules, antenna, antennal scale, chelipeds, and other pereiopods markedly resembling those of that species. Fingers of chelae with yellowish tips. Ventral surface of body pinkish cream.

TYPES.—Holotype, allotype, and “morphotype,” USNM 82261 (I, , II); paratypes, USNM.

TYPE-LOCALITY.—Stream 5 miles northeast of Swainsboro (North Prong of the Canoochee River) on U.S. Highway 25, Emanuel County, Georgia.

RANGE.—This crayfish, endemic to Georgia, occurs in the Ogeechee, Canoochee, and Newport basins from Burke, Emanuel, and Jenkins counties downstream, probably almost to the lower parts of the rivers influenced by the tides. This area lies wholly within the Vidalia Upland and Barrier Island Sequence districts of the Coastal Plain Province.

GEORGIA SPECIMENS EXAMINED.—I have examined a total of 247 specimens from the following localities. Bryan County: (1) Savage Creek 2 mi S of Pembroke on St Rte 119, 1j, 2j, 27 Dec 1971, G. K. Williamson, collector; 1I, 9II, 2f;, 22 Jun 1975, D. J. Peters, J. E. Pugh, HHH; 4I, 1II, 1, 20 Apr 1977, C. E. Carter, JEP, HHH; (2) roadside ditch and conduit at south city limit of Pembroke on St Rte 119, 1, 22 Jun 1975, DJP, JEP, HHH. Bulloch County: (3) Lotts Creek 5.8 mi S of Statesboro on US Hwy 25 (Hobbs, 1947a:12), 1II, 27 Mar 1939, H. H. Wallace, HHH; 1II, 1, 1j, 28 Mar 1950, W. J. Houck; 1j, 1j, 25 Jul 1950, WJH; (4) Lotts Creek 2.7 mi E of Emanuel Co line on US Hwy 80, 1j, 5 Oct 1977, T. A. English, Jr., HHH; (5) Wyatts Creek 14.2 mi S of Millen on US Hwy 25 (Hobbs, 1947a:12), 2I, 1II, 1, 2j, 2j, 17 Apr 1944, HHH; (6) trib to Lotts Creek 13 mi N of Claxton on US Hwy 25 (Hobbs, 1947a:12), 2j, 5j, 17 Apr 1944, HHH; (7) 1.2 mi NE of Denmark in spring-fed roadside ditch, 2I, 7II, 8, 9j, 25j, 14 Dec 1971, GKW; 1I, 5II, 6, 2j, 8j, 19 Dec 1971, GKW; (8) Black Creek 3 mi N of Denmark, 4II, 8, 2j, 2j, 22 Apr 1971, GKW; (9) Pole Branch 0.3 mi E of US Hwy 80 on St Rte 119, 1j, 19 Apr 1977, CEC, C. W. Hart, Jr., JEP, HHH; (10) roadside ditch 1.9 mi E of US Hwy 80 on St Rte 119, 1, 19 Apr 1977, CEC, CWH, JEP, HHH. Burke County: (11) Mill Creek 10.4 mi N of Millen on US Hwy 25 (Hobbs, 1947a:12, erroneously reported as Jenkins County), 2I, 9II, 9, 1j, 8j, 27 Mar 1939, HHW, HHH. Candler County: (12) Canoochee River 4 mi W of Metter on St Rte 46, 1II, 4, 2j, 1j, 24 Mar 1950, D. C. Scott; 2j, 25 Mar 1950, E. C. Raney; (13) Fifteen Mile Creek at St Rte 46, 1, 25 Mar 1950, ECR; 4I, 4II, 1, 3j, 16 Aug 1957, R. D. Suttkus; (14) Sams Creek at St Rte 46 W of Metter, 1I, 1j, 30 May 1969, E. T. Hall, Jr., HHH. Emanuel County: (15) type-locality, 2I, 3II, 6, 1j, 13 Apr 1944, HHH; (16) Fifteen Mile Creek 3.1 mi E of Twin City on US Hwy 80, 1, 5 Oct 1977, TAE, HHH. Evans County: (17) Thick Creek 5.5 mi N of Claxton on US Hwy 301 (Hart and Hart, 1974:21), 1I, 2II, 3, 7j, 6j, 23 Dec 1956, HHH; (18) Canoochee River just off US Hwy 301, 1j, 11 Aug 1976, K. W. Martin, M. W. Walker. Jenkins County: (19) Sculls Creek 9.6 mi S of Millen at US Hwy 25 (Hobbs, 1947a:12), 2I, 1, 2j, 3j, 27 Mar 1939, HHW, HHH; (20) Bay Gull Branch 11.6 mi S of Millen on US Hwy 25 (Hobbs, 1947a:12), 3II, 1, 17 Apr 1947, H. W. Fowler. Liberty County: (22) trib of Newport River at St Rte 38, 2I, 1II, 15 Jun 1948, RDS. Screven County: (23) Ogeechee River at Bulloch Co line at St Rte 24, 1, 19 Apr 1977, CEC, CWH, JEP, HHH. Tattnall County: (24) Billy Fork Creek 3 mi W of Evans Co line on US Hwy 280, 2I, 1II, 2, 4j, 22 Jun 1975, DJP, JEP, HHH.

VARIATIONS—As pointed out by Hobbs (1947a:13), the rostrum is variable in length, reaching from the level of the end of the antennular peduncle to “scarcely reaching distal end of penultimate segment….” Whereas the rostral margins may be gently or strongly convergent, the marginal spines are always present, although ranging from well-developed to vestigial acute tubercles. Similarly, the postorbital and cervical spines may be strong or weak. The first form males collected in Tattnall County differ from others observed in possessing a conspicuously shorter cephalic process on the first pleopod (Figure 160d,h), one that extends no farther distally than the level of the tip of the central projection. In specimens from elsewhere, the cephalic process distinctly overreaches the central projection. The apparent differences in the cephalic hump on the first pleopod in Figure 160 reflect, for the most part, the angle at which the appendages were positioned for illustration (to show both the central projection and caudal process); the hump is much better depicted in Figure 158b,g. The ventral face of the annulus ventralis exhibits a striking degree of variation, ranging from being virtually flat to slightly convex, or, more typically, traversed by a median longitudinal, caudally expanding depression (dorsally), and in at least one specimen bearing a well-defined posteromedian subconical protuberance. In most of the young females, the surface is plane, but similarly it is also almost flat in a number of the larger females—for example, in several from Jenkins and Tattnall counties. In large females from Bryan County the concavity is equally as prominent as it is in specimens from the type-locality (near the northern extremity of the range). An insufficient number of specimens is available to determine whether any of the variations noted above are regionally restricted.

SIZE.—The largest specimen that I have examined is a first form male, having a carapace length of 41.0 (postorbital carapace length 30.0) mm. Corresponding lengths of the smallest first form male and largest female are 28.1 (21.0) mm and 37.4 (28.9) mm, respectively.