Comprehensive Description
provided by Smithsonian Contributions to Zoology
Procambarus (Scapulicambarus) troglodytes (LeConte)
Astacus troglodytes LeConte, 1856:400*.—Hagen, 1870:9*, 42*, 43.
Astacus fossarum LeConte, 1856:401* [syntypes, MCZ 3377 (I dry), ANSP 314 (); type-locality, ditches, lower Georgia].—Hagen, 1870:9*, 10, 43.—Faxon, 1884:136; 1885a: 28*.—Underwood, 1886:373*.—Harris, 1903a:107*, 130*.—Hobbs, 1972a:2*.
Astacus maniculatus LeConte, 1856:401*[types not extant; type-locality, ditches, lower Georgia].—Hagen, 1870:10.—Hobbs, 1972a:2*; 1974b:66*.
Cambarus troglodytes.—Hagen, 1870:20, 37, 38, 41–43* [in part], 44, 45, 48, 97*, 100*, 106, pl. I: figs. 11–14, pl. III: fig. 141.—Forbes, 1876:18.—Faxon, 1884:136–137*, 138; 1885a:8, 10, 21, 22, 26–28*, 29, 37, 157*, 167*, 169, 173*, 179; 1885b:358; 1914:414*.—Underwood, 1886:373*.—Hay, 1899b:959*.—Ortmann, 1902:277.—Harris, 1903a: 58*, 107, 130*, 138*, 142, 143, 151, 152*, 154, 156.—Newcombe, 1929:279.—Crocker, 1957:30.—Hobbs, 1972a:2.
Cambarus troglodytus.—Hagen, 1870:33 [erroneous spelling].
Cambarus maniculatus.—Hagen, 1870:34, 52–53*, 83, 97*, 100*, 107.—Faxon, 1884:137*; 1885a:8, 19, 29, 158*, 167*, 173*; 1914:427*.—Underwood, 1886:370*.—Harris, 1903a:107*, 151, 152*.—Hobbs, 1972a:2.
Cambarus fossarum.—Hagen, 1870:53, 100*.—Faxon, 1885a:27.
Cambarus troglodyles.—Herrick, 1882:254 [erroneous spelling].
Cambarus (Cambarus) troglodytes.—Ortmann, 1905a:102, 105*, 128*, 129; 1905d:437.
Cambarus (Ortmannicus) troglodytes.—Fowler, 1912:341 [by implication].—Creaser, 1934:4 [by implication].
Procambarus troglodytes.—Hobbs, 1942a:342 [by implication]; 1942b:99, 100, 105; 1952b:165, 173*, fig. 2; 1958a:88; 1958b:163; 1959:885*; 1962:273, 290*, 291, fig. 61; 1966b: 68, 70, 71; 1968b:K-11*, fig. 22c.—Hobbs and Freeman, 1956:10.–Crocker, 1957:30.—Crawford, 1959:150, 151, 156, 162, 171, 172, 177, 180, 181.—Hobbs III, 1969:42.—Hart and Hart, 1974:21*, 22, 28, 32*, 33, 71, 88*, 91, 131*.—Page, 1974:97*.—Peters, 1975:20, 22.—Wharton, 1978:46*.
Procambarus paeninsulanus.—Hobbs, 1942b:105* [in part].
Procambarus (Scapulicambarus) troglodytes.—Hobbs, 1972a:12; 1972b:72*, 152*, 154*, 155, fig. 56e; 1974b:66*, fig. 284; 1977a:419.—Hobbs III, Thorp, and Anderson, 1976:3, 10, 43*–44, figs. 19, 24.
These citations are believed to constitute a complete bibliography for the species; those followed by an asterisk contain references to Georgia.
SUMMARY OF LITERATURE.—Following the description of this crayfish by LeConte (1856), apparently there was some confusion on the parts of several of the earlier workers as to the identity of the species (Faxon, 1884:137–138), but with the appearance of Hagen's (1870) monograph, except for erroneous localities (all of those outside of Georgia and South Carolina), the identity of LeConte's species became clear, and both Hagen and Faxon (1885a) agreed that LeConte's Astacus fossarum was a synonym of the species they called Cambarus troglodytes. There is no evidence that any subsequent student of crayfishes saw one of LeConte's specimens of his Astacus maniculatus, and his description of it does not permit its separation from subsequently obtained specimens of his A. troglodytes, in which the areola suture is very slender, virtually reduced to a line, apparently the only character prompting Hagen (1870:53) to recognize Cambarus maniculatus. Faxon (1884:137) listed Cambarus maniculatus as occurring in “Lower Georgia,” but noted that it was “known only through LeConte's description, which perhaps was drawn up from an immature specimen of C. troglodytes.” Faxon (1885a:29) also listed it in his revision of the Astacidae but reiterated the above statement, and, in 1914 (p. 427), listed it as a “doubtful species.” No further disposition of, or comments on, LeConte's A. maniculatus appeared until Hobbs (1974b:66) included it along with Astacus fossarum under the synonomy of Procambarus (Scapulicambarus) troglodytes.
Faxon (1885a:27–28) summarized the known locality records including three in South Carolina (Charleston, Oakley, and Columbia), two in Georgia (neighborhood of Augusta, Richmond County, and “Lower Georgia”), and one in Illinois, the latter based on a specimen for which he questioned the accuracy of the locality label. Certainly this species does not occur in Illinois. Although several subsequent new records of the occurrence of this crayfish in South Carolina have appeared (Hobbs and Freeman, 1956; Crawford, 1959; Hart and Hart, 1974; and Hobbs III, Thorp, and Anderson, 1976), only four additional records have been cited for Georgia (Hart and Hart, 1974): in Burke, Chatham, Liberty, and McIntosh counties. The studies of Crawford and of Hart and Hart are directed toward a knowledge of the ostracod symbionts of crayfishes, and the ostracods reported by the latter in Georgia were obtained from crayfishes used in the present study. The best existing account of what little is known of the species is that of Hobbs III, Thorp, and Anderson (1976). All other references prior to 1972 that are cited in the synonomy consist of keys, repeat information presented by Hagen or Faxon, are concerned with statements of affinities of this crayfish with other, for the most part, new species, or involve nomenclatural changes. Those appearing subsequent to 1972 add little to our knowledge of the species.
DIAGNOSIS.—Rostrum usually with marginal spines, tubercles, or angles at base of acumen, and rarely with low median carina. Carapace with 1 pair of cervical spines or tubercles. Areola 13.9 (rarely less than 18) to more than 50 (average 29.1) times as long as wide and constituting 31.9 to 37.6 (average 35.0) percent of entire length of carapace (41.5 to 47.7, average 44.9, percent of postorbital carapace length). Antennal peduncle with or without tubercle (adults rarely with strong spine) on ischium. Ventral surface of basis and usually proximal half of ischium of third maxilliped with variable quantity of long plumose setae among simple stiff ones. Basis of cheliped without mesial spine. Mesial surface of palm of chela of male with row of 5 to 8 (usually 6) prominent tubercles. Male with simple hook on ischia of third and fourth pereiopods, neither opposed by tubercle on corresponding basis, and conspicuous caudomesial boss on coxae of fourth and fifth pereiopods. First pleopods asymmetrical and reaching coxae of third pereiopods; cephalic surface of left member of pair with prominent shoulder (that of right member folded caudomesially in first form male) at base of distal third of shaft; latter with convex caudal margin distal to level of shoulder; subapical setae moderately abundant and situated laterally; mesial process acute, rather short, directed caudodistally, its tip often bent mesially; cephalic process, most conspicuous of terminal elements, forming large, laterally compressed, distally rounded lobe borne on cephalodistal half of shaft; central projection corneous, acute, and usually largely obscured, particularly in lateral aspect, by caudal element; latter highly variable with caudal knob and corneous process usually not clearly delimited, latter either forming prominent caudodistal ridge or scooplike prominence on caudodistal extremity of shaft; adventitious process consisting of corneous ridge mesially. Female with sternum anterior to annulus ventralis usually unadorned, very rarely bearing single pair of low, symmetrically arranged prominences; cephalomedian part of annulus with paired, rounded elevations, together forming oval to rounded eminence almost bisected by cephalic part of sinus; first pleopod present.
MALE, FORM I (from 7.6 miles west of Midway on State Route 38, Liberty County, Georgia).—Body (Figure 192a,h) subovate, compressed laterally. Abdomen narrower than thorax (16.3 and 19.5 mm). Width of carapace slightly greater than depth at caudodorsal margin of cervical groove (19.5 and 18.7 mm). Areola 38.3 times as long as broad, with 1 punctation in narrowest part. Cephalic section of carapace 1.7 times as long as areola, length of latter 37.4 percent of total length of carapace (46.2 percent of postorbital carapace length). Rostrum subplane dorsally with slender convergent margins weakly angulate at base of acumen, lacking marginal spines or tubercles; upper surface with scattered punctations between submarginal rows; acumen clearly defined basally and reaching anteriorly to base of ultimate podomere of antennular peduncle; subrostral ridges weak and evident in dorsal view along no more than basal fifth of rostrum. Postorbital ridges well developed, grooved dorsolaterally, and ending cephalically in very small tubercles. Suborbital angle rounded and almost obsolete. Branchiostegal spine moderately strong. Carapace punctate dorsally and tuberculate laterally, thickly so in anteroventral branchiostegal area, tubercles rather sparse cephalolaterally except in mandibular adductor region and along cervical groove in mandibular region; cervical spine acute, rather small, and flanked dorsally by tubercle slightly larger than others nearby. Abdomen subequal in length to carapace (39.2 and 40.9 mm). Cephalic section of telson with 4 spines in right and 3 in left caudal corners, all fixed except that immediately lateral to mesialmost on both sides. Uropods with both lobes of basal podomere bearing corneous spine; mesial ramus with distinct spine on lateral margin and distomedian one far removed from margin; lateral ramus with usual row of small spines immediately proximal to transverse suture and larger ones at lateral extremity of suture. Cephalic lobe of epistome (Figure 192k) broadly rounded, with short, subangular anteromedian prominence, flanked laterally by weak marginal undulations; main body with conspicuous fovea in suboval depression; epistomal zygoma arched. Antennule of usual form, with rather prominent spine near midlength of ventral surface. Antenna extending caudally slightly beyond base of telson; peduncle with acute lateral spine on basis and rather small acute tubercle on ventral surface of ischium; antennal scale (Figure 192g) about 2.3 times as long as wide, broadest at about midlength, where lamellate section about 2.4 times as broad as thickened lateral part, latter terminating in moderately strong corneous-tipped spine. Ventral surface of ischium of third maxilliped studded with conspicuous mat of long and short plumose setae (becoming somewhat shorter in distal third) among and outnumbering stiff simple ones.
Right chela (Figure 192j) about 3.0 times as long as broad, subovate in cross section and somewhat depressed. Mesial surface of palm with row of 7 tubercles subtended dorsally and ventrally by irregular rows of 3 to 5; entire palm tuberculate. Fixed finger with low, rounded median longitudinal elevation dorsally and ventrally, flanked by tubercles proximally and setiferous punctations along at least distal four-fifths; lateral margin of finger with row of similar punctations; opposable margin with row of 13 tubercles along proximal two-thirds, proximal 4 increasing in size distally, fifth much smaller than fourth, and more distal ones decreasing in size distally; additional row of 7 (6 on left chela) tubercles present on lower level, penultimate member, situated near base of distal third, largest; minute denticles forming single row along middle third of finger and arranged in band along distal third. Dactyl with dorsal and ventral surfaces similar to those of fixed finger, mesial surface with row of 4 tubercles, decreasing in size distally, along basal third of finger; opposable margin with row of 14 tubercles extending along proximal two-thirds, fourth from base largest, first next, otherwise decreasing in size distally; width of dactyl narrower proximal to level of fourth tubercle than in middle third; minute denticles occurring between all tubercles distal to fourth from base and forming band between distalmost tubercle and corneous tip of finger.
Carpus of right cheliped longer than broad (12.2 and 8.3 mm), mesial and dorso- and ventromesial surfaces tuberculate, otherwise punctate; larger tubercles as follows: 1 on mesial surface, 1 at dorsomesial distal angle, 1 on ventrolateral condyle, and another on ventral distomesial margin.
Merus of right cheliped tuberculate dorsally, ventrally, and distomesially, punctate elsewhere; dorsal surface with 2 subspiniform tubercles near distal margin and smaller one distomesially on margin; ventral surface with irregular lateral row of 14 (left with 12) tubercles, more regular mesial row of 16 (left with 18) and oblique distal row of 5 joining mesial and lateral rows; tubercles of mesial and lateral rows not graduated in size, but in general more distal ones larger. Ischium with row of 5 small tubercles.
Hooks on ischia of third and fourth pereiopods (Figure 192i), both simple and that on third overreaching basioischial articulation, neither opposed by tubercle on basis. Coxa of fourth pereiopod with conspicuous, vertically oriented caudomesial boss; that on coxa of fifth less prominent and compressed in longitudinal plane of body.
Sternum between third, fourth and fifth pereiopods moderately deep and bearing fringe of plumose setae on ventrolateral margins.
First pleopod (Figure 192b,f,l) as described in “Diagnosis.”
FEMALE (also from 7.6 miles west of Midway, Liberty County, Georgia).—Differing from first form male, other than in secondary sexual characters, as follows: rostrum with minute marginal tubercles at base of acumen; suborbital angle obsolete; cervical and branchiostegal spines very small; cephalic section of telson with 3 spines in each caudolateral corner but with rudiment of fourth (mesially) in both; epistome with small spine on anterodextral border; spines on basis and ischium of antennal peduncle reduced in size, rather inconspicuous; chela (Figure 183h) about 2.4 times as long as broad, mesial margin of palm with row of 6 tubercles; opposable margin of fixed finger with single row of 10, third from base largest, and more ventral row represented by single large tubercle at base of distal third, minute denticles arranged in single row; opposable margin of dactyl with row of 11 tubercles; both fingers with moderately conspicuous tufts of plumose setae at ventral base; tubercle on dorsodistal margin of merus very small, mesial and lateral rows on ventral surface consisting of 13 tubercles each and 4 in oblique row; ischium with row of 4 tubercles. (See “Measurements.”)
Annulus ventralis (Figure 192d) subspindle shaped, approximately 2.2 times as wide as long, lateral parts less strongly sclerotized than median three-fifths; weakly sculptured except in cephalomedian area, where paired elevations (together forming subcircular prominence) bisected by cephalic part of sinus, latter, following slightly tilted S-shaped course along median line, terminating short distance anterior to caudal margin of annulus. Postannular sclerite subtriangular, about 1.9 times as broad as long, and half as long and almost 0.42 as wide as annulus, and rather strongly arched transversely near midlength. Sternum immediately anterior to annulus lacking tubercles or prominences. First pleopod reaching slightly anterior to caudal margin of sternum between fourth pereiopods.
MALE, FORM II (from Gouldins Creek off State Route 82, Liberty County, Georgia).—Differing from first form male in following respects: marginal spines on rostrum well defined, acumen slightly overreaching antennular peduncle; postorbital, cervical, and branchiostegal spines well developed; cephalic section of telson with 3 spines in each caudolateral corner; epistome more truncate anteriorly, with anterolateral acute prominences; antennal peduncle with well-developed spines on basis and ischium; third maxilliped with less conspicuous plumose setae on lateral half of ventral surface of ischium; opposable surface of fixed finger of chela with 13 tubercles in dorsal row and only 2 representing ventral row, corresponding surface of dactyl with row of 12 tubercles; distal part of band of minute denticles on opposable margins of both fingers narrower than in first form male; ventral surface of merus with lateral row of 14 tubercles, mesial of 15, and oblique one represented by 2; ischium with 4; hooks on ischia of third and fourth pereiopods and bosses on coxae of fourth and fifth pereiopods greatly reduced in size. (See “Measurements.”) First pleopod (Figure 192c,e) with distal part less caudally inclined, anterior-posterior plane of cephalic process longer, and caudal knob area of caudal element not so distinctly delimited from caudal process; left pleopod with cephalic shoulder not folded mesially; juvenile oblique suture clearly defined.
COLOR NOTES (Figure 182a).—Carapace reddish brown with brick red to black markings dorsally, fading to pinkish cream ventrally; rostrum, more red than brown dorsally, with black margins; postorbital ridges, paired spots on gastric region, and paired dorsolateral stripes on branchiostegites also black; these stripes extending from, or almost from, areola caudally to caudal flange, flange and ventral margin of carapace black; cephalic triangular part of areola brick red; anterior part of antennal, mandibular, and anteroventral branchiostegal regions pinkish cream to white. Abdomen with broad, median dorsal dark brown stripe extending from first to sixth abdominal tergum, it, in turn, flanked by narrower pinkish cream stripes flecked with red, and these stripes delimited ventrally by black, somewhat undulating (often broken) line at base of pleura; remainder of latter dark brown, flecked with red and occasionally with cream to white spot adjacent to ventral margin. Dark dorsomedian stripe on abdomen sometimes bisected by lighter median one extending from second onto sixth tergum. First through fifth terga with dark red caudal margin. Telson and uropods tan to brown, flecked with red. Antennule and antenna mostly reddish brown. Cheliped, from midlength of merus distally, dark brown with reddish orange to orange tubercles, and ventral surface orange red; remaining pereiopods orange cream proximally, becoming dark brown on distal part of merus, then progressively lighter distally; ventral surface of body orange to pinkish cream.
Measurements (mm)
Male, form I Female Male, form II
Carapace
Height 18.7 16.5 14.9
Width 19.5 16.4 15.0
Entire length 40.9 35.0 33.1
Postorbital length 23.1 27.9 25.5
- bibliographic citation
- Hobbs, Horton Holcombe, Jr. 1981. "The Crayfishes of Georgia." Smithsonian Contributions to Zoology. 1-549. https://doi.org/10.5479/si.00810282.318
