Procambarus howellae Hobbs 1952

Procambarus (S.) howellae

E Ankylocythere ancyla: Wheeler (Hart and Hart, 1974:22)

Ankylocythere hobbsi: Laurens (Hart and Hart, 1974:28)

Ankylocythere sinuosa: Bleckley (Hart and Hart, 1974:30)

Ankylocythere telmoecea: Twiggs (Hart and Hart, 1974:32)

Ankylocythere tiphophila: Telfair, Wilkinson (Hart and Hart, 1974:33)

Entocythere internotalus: Dooly (Hart and Hart, 1974:90)

Uncinocythere lucifuga: Bibb, Bleckley, Dodge, Twiggs (Hart and Hart, 1974:131)

Procambarus (Scapulicambarus) howellae Hobbs

Procambarus howellae Hobbs, 1952b:167, figs. 1, 4, 5, 8–14.

Procambarus (Scapulicambarus) howellae.—Hobbs, 1972a:12; 1974b:65, fig. 281; 1981:469, figs. 16b, 182b, 183f, 184–188, 260.

TYPES.—Holotype and allotype, USNM 93158 (male I, female); morphotype, USNM 93159 (male II); paratypes, MCZ, USNM.

TYPE LOCALITY.—Drainage ditch on campus of Wesleyan College, Rivoli, Bibb County, Georgia.

RANGE.—Lower piedmont and upper coastal plain of Georgia in the middle Flint and Altamaha river basins.

HABITAT.—Lotic and lentic situations and burrows (tertiary burrower).

Procambarus (Scapulicambarus) howellae Hobbs

Procambarus howellae Hobbs, 1952b:167, figs. 1, 4, 5, 8–14.

Procambarus (Scapulicambarus) howellae.—Hobbs, 1972a: 12.

TYPES.—Holotype and allotype, USNM 93158 ( I, ); morphotype, USNM 93159 ( II); paratypes. MCZ, USNM.

TYPES-LOCALITY.—Drainage ditch on campus of Wesleyan College, Rivoli, Bibb County, Georgia.

RANGE.—Lower piedmont and upper coastal plain of Georgia between the Ocmulgee and Ogeechee rivers.

HABITAT.—Lotic and lentic situations.

Procambarus (Scapulicambarus) howellae Hobbs

Procambarus howellae Hobbs, 1952b:167–173, figs. 1–14; 1959: 885; 1962:290, 291, fig. 63; 1968b:K-9, fig. 22e.—Villalobos, 1959:312.—Hart and Hart, 1974:22, 28, 30, 32, 33, 90, 131.

Procambarus (Scapulicambarus) howellae.—Hobbs, 1972a:12; 1972b:71, 151, 154, fig. 56a; 1974b:65, fig. 281; 1977a: 419.

These citations are believed to constitute a complete bibliography of the species. All of the references pertain to Georgia.

SUMMARY OF LITERATURE.—This crayfish was described by Hobbs (1952b), who reported it from lotic and lentic habitats in three localities, one each in Bibb, Emanuel, and Telfair counties, Georgia. Except for discussions of relationships to other crayfishes, its assignment to the subgenus Scapulicambarus, its inclusion in keys, and statements concerning its range, no noteworthy information appeared in the literature until 1974. Hart and Hart (1974) reported this Georgia endemic from Bibb, Bleckley, Dooly, Telfair, Twiggs, Wheeler, and Wilkinson counties, where it served as hosts to entocytherid ostracods. The most recent reference includes a statement concerning its relationship to a Mexican crayfish, Procambarus (S.) strenthi.

DIAGNOSIS.—Rostrum usually with marginal spines, tubercles, or angle at base of acumen and lacking median carina. Carapace with 1 pair of cervical spines or tubercles. Areola in adults 9 to 35.3 (as little as 7 in juveniles) times as long as broad and constituting 29.6 to 36.8 percent of entire length of carapace (39.9 to 47.7 percent of postorbital carapace length). Antennal peduncle with spine (rarely reduced to tubercle) on ischium. Ventral surface of basis and ischium of third maxilliped not covered with dense plumose setae. Basis of cheliped without mesial spine. Mesial surface of palm of chela bearing prominent row of 6 to 9 tubercles. Male with simple hooks on ischia of third and fourth pereiopods, that on fourth opposed by tubercle on corresponding basis and conspicuous caudomesial boss on coxae of fourth and fifth. First pleopods asymmetrical and reaching coxae of third pereiopods; cephalic surface of left member of pair with prominent (usually acute) angular shoulder (that on right member folded caudomesially in first form male) at base of distal third of shaft and in lateral view latter tapering distally; subapical setae rather sparse; mesial process slender, acute, and directed caudally to caudodistally, sometimes almost at right angle to shaft of appendage; cephalic process short, acute, and situated lateral to central projection; latter dentiform, with apex directed caudomesially; caudal element consisting of caudal process closely applied to caudolateral surface of central projection and adventitious ridgelike prominence flanking caudal and mesial base of projection. Female with cephalomedian part of annulus ventralis partly concealed beneath paired projections from often multituberculate sternum immediately anterior to annulus; first pleopod present.

COLOR NOTES (Figure 182b).—Carapace dark reddish brown to brown dorsally, with scattered irregular darker spots; rostral margins, postorbital ridges, and pair of spots of gastric region black. Broad pinkish splotch extending caudoventrally from antennal region across mandibular area, narrow one flanking postorbital ridge, and third irregular one in ventral hepatic area; posterior hepatic and mandibular adductor regions dark brown; cervical groove black. Branchiostegite with black longitudinal stripe laterally, extending from level opposite base of abdominal pleura almost to cervical groove; posteriorly, stripe continuous with black area covering caudal flange and extending along ventral margin of branchiostegite; area between black stripe and dark ventral area pinkish cream with brown and small white irregular spots. Cephalic half of first abdominal tergum with transverse black bar bearing posteromedian notch, caudal half dark pinkish tan, and reduced pleuron bright pink. Remaining segments of abdomen with dorsal part of tergum bearing black band anteriorly, followed by broader dark brown one, and slightly paler narrower one along caudal margin; lateral part of terga with broad pinkish tan stripe interrupted by narrow black bands connecting anterodorsal band with irregular black to dark brown splotches on bases of corresponding pleura; remainder of pleura brick red. Telson reddish brown, with very narrow black band basally and paired lateral and median longitudinal dark brown stripes in cephalic section. Uropods also dark reddish brown, both rami slightly darker mesially than laterally. Antennular and antennal peduncles mostly tan to dark brown, but with black markings; flagella brown to olive tan. Third maxilliped pale olive tan, with orange markings on more distal articular membranes. Cheliped, from distal part of ischium to yellowish tips of fingers black to slightly diluted orange black dorsally; tubercles bright orange; ventral surface of distal podomeres also orange. Dorsal surface of other pereiopods olive tan on distal part of ischium, intensifying to olive brown at end of merus; carpus somewhat paler, and propodus and dactyl dilute pinkish orange (some individuals with entire pereiopods pinkish orange with brownish mottlings dorsally). Ventral region of cephalothorax pinkish to pale orange.

TYPES.—Holotype and allotype, USNM 93158 (I, ); morphotype, USNM 93159 (II); paratypes, MCZ, USNM.

TYPE-LOCALITY—Drainage ditch on campus of Wesleyan College, Rivoli, Bibb County, Georgia.

RANGE.—Endemic in Georgia, where widespread in the coastal plain of the Flint and Altamaha river basins, occurring most abundantly in the Fall Line Hills and Vidalia Upland districts.

GEORGIA SPECIMENS EXAMINED.—I have examined a total of 379 specimens from 54 localities (Figure 185) in the following counties in Georgia: Ben Hill (1), Bibb (1), Bleckley (2), Dodge (5), Dooly (2), Emanuel (1), Houston (1), Jeff Davis (1), Johnson (1), Laurens (3), Long (1), Macon (1), Marion (1), McIntosh (1), Montgomery (3), Pulaski (2), Schley (1), Screven (1), Sumter (1), Telfair (6), Toombs (1), Twiggs (1), Washington (2), Wheeler (4), Wilcox (7), and Wilkinson (3).

VARIATIONS.—Most conspicuous among the variations observed in this species is the rostrum (Figure 186) in which, although always possessing margins that are convergent to the base of the acumen, the degree of convergence is highly variable, and the usual marginal spines may be reduced to small tubercles or to obtuse angles that become abraded in late intermolt stages. The areola ranges in width from less than 9 times as long as broad (in most juveniles with a carapace length of less than 25 mm) to as much as 35.3 times in a first form male from Pulaski County, having a carapace length of 40.3 mm. The ratios of the length of the areola to that of the entire length of the carapace range in adults from 30.7 to 36.8 (average 33.1) percent, that of the length of the areola to the postorbital carapace length 39.9 to 47.7 (average 43.7) percent. There appears to be no correlation between the width of the areola and the size of the adult animal, but there is some evidence that the young have a proportionately broader and shorter areola than do the adults and that it becomes narrower and longer with increase in carapace length up to about 30 mm. At greater carapace lengths the wide range of variation pointed out in the “Diagnosis” exists. Of the specimens measured, only two have areolae that are as much as 20 times as long as wide. The mesial margin of the palm bears a row of six to nine tubercles (seven occur most frequently). The presence of a tubercle on the basis of the fourth pereiopod of the male that opposes the hook on the ischium (Figure 184l) is erratic; it may be present or absent in males from the same locality. Variations in the first pleopod of the male, form I, are illustrated in Figure 187. A rather striking variation occurs in the sternum immediately anterior to the annulus ventralis in the female (Figure 188); it may bear several small, rounded tubercles, or there may be two that are much larger than the others that project caudally some distance over the anteroventral face of the annulus. In juvenile and most second form males, the shoulder on the right first pleopod is a virtual mirror image of that on the left, but in the first form male it is always bent caudomesially.

SIZE.—The largest specimen available is a first form male, having a carapace length of 45.2 (postorbital carapace length 34.1) mm. Corresponding lengths of the smallest first form male and of the only known ovigerous female are 28.3 (20.6) mm and 29.3 (22.9) mm, respectively.