6 April 1998 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 111(1):81-91. 1998. A new species of crayfish of the genus Procambarus, subgenus Ortmannicus (Decapoda: Cambaridae), from the Waccamaw River basin, North and South Carolina John E. Cooper North Carolina State Museum of Natural Sciences, P. O. Box 29555, Raleigh, North Carolina 27626, U.S.A. Abstract.—Procambarus (Ortmannicus) braswelli is a new species of cray- fish from the Waccamaw River basin in North and South Carolina. A primitive member of the Pictus Group, P. braswelli has its closest affinities with P. (0.) chacei, P. (O.) enoplosternum, and P. (O.) pictus. The new species is less closely related to P. (O.) epicyrtus, and distantly related to its geographically nearest relative, P. (O.) lepidodactylus, with which it has been confounded. The occurrence of P. lepidodactylus in North Carolina is currently uncon- firmed. Procambarus braswelli may be distinguished from the other members of the Pictus Group by its combination on the form I male gonopod (first pleopod) of a prominent, truncated, distally directed caudal knob; a large, somewhat bulbous adventitious process; and a long, caudodistally directed me- sial process; and by a long acumen. The Waccamaw River basin of south- maw River, apparently 7.5 air mi. [12.0 air eastern North Carolina and northeastern km] south of Lake Waccamaw, Columbus South Carolina has long been known as County (1949)" (Cooper & Cooper 1977b: home to a number of animal species that 206). This record was based on a female in are either endemic or are shared with a sin- the collections of the National Museum of gle other river basin. The endemic fauna Natural History, Smithsonian Institution includes several fishes and mollusks. Infor- (USNM 129841), collected on 29 March mation on the fishes can be found in Hubbs 1949 by E. C. Raney. It is the only North & Raney (1946), Frey (1951), Shute et al. Carolina specimen identified as P. lepido- (1981), Menhinick (1991), and Rohde et al. dactylus in the catalogued collections of (1994). The mollusks are discussed in Ful- that institution, and the locality is obviously ler (1977), Johnson (1984), and Porter & the same one referred to as "Columbus Horn (1984). Teulings & Cooper (1977: County" by Hobbs (1968:K9, 1972:61, 414-415) provided a list of the endemic 1974:57, 1989:68). None of the North Car- species. olina specimens later assigned to P. lepi- Included in the Waccamaw invertebrate dodactylus had received critical examina- fauna is a crayfish previously assigned to tion. Prompted by a form I male collected Procambarus (Ortmannicus) lepidodactylus by David R. Lenat, North Carolina Division Hobbs, 1947a, a species considered the of Water Quality, I determined that these northernmost representative of the primitive specimens represent an undescribed species Pictus Group (Hobbs 1958a, 1962, 1968, of the Pictus Group that appears to be en- 1972, 1974, 1989; Cooper & Cooper 1977a, demic to the Waccamaw River basin and 1977b). Few specimens of this Waccamaw that is only distantly related to P. lepido- crayfish have been collected, and the only dactylus. This new species is currently published locality was "canal off Wacca- known only from Columbus County, North 82 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Carolina, and from a single locality in Hor- Hobbs, 1968.K9 (p.p.; Columbus Coun- ry County, South Carolina, but it may be ty, North Carolina).—Hobbs, 1972:151 found elsewhere within the Waccamaw ba- (p.p., North Carolina).—Franz & Lee, sin. 1982:61 (p.p.; North Carolina).—Le- Because P. lepidodactylus (s.s.) occurs in Grand & Hall, 1997:32 (p.p.; Waccamaw the Pee Dee River basin in South Carolina, drainage, North Carolina). Cooper & Cooper (1977b:207) speculated Procambarus (Ortmannicus) lepidodacty- that it "may yet be discovered in tributaries lus.—Cooper & Cooper, 1977a: 198, of the Lumber River of North Carolina . 1977b:206, 207 (p.p.; North Carolina).— . " A distribution map showing localities Cooper & Cooper, 1977a:200 (p.p.; by for members of the Pictus Group (Hobbs implication, North Carolina).—Hobbs, 1958a:72) contains a single North Carolina 1972:61, 1974:57, 1989:68 (p.p.; Colum- site for "P. lepidodactylus." The site indi- bus County, North Carolina).—Hobbs & cated by a dot in the map lies just west of Peters, 1977:8 (p.p.; North Carolina).— the 79th meridian, which would place the Hobbs et al„ 1977:19 (p.p.; North Caro- locality in the Lumber River basin. How- lina).—'Teulings & Cooper, 1977:415 ever, the dot undoubtedly was meant to rep- (p.p.; North Carolina).—Fitzpatrick, resent the Columbus County record in the 1983:214 (p.p.; Carolinas, viz. North Waccamaw basin (USNM 129841). I know Carolina).—Hobbs & Franz, 1986:516 of no specimens of Procambarus from (p.p.; North Carolina).—Hobbs, 1989:86 North Carolina that incontrovertibly can be (p.p.; North Carolina). assigned to P. lepidodactylus. Several spec- Procambarus leptodactylus.—Williams et imens that could belong to this species have al., 1989:26, 64 (p.p.; by implication, been collected in the Lumber basin (Cooper North Carolina; erroneous spelling).— & Braswell 1995:120), but form I males LeGrand, 1993:23, LeGrand & Hall, have yet to be seen. 1995:31 (p.p.; Waccamaw drainage, Abbreviations used in the text are: j = North Carolina; erroneous spelling). juvenile; NC = North Carolina state high- "Undescribed species."—Cooper & Bras- way; NCSM = North Carolina State Mu- well, 1995:120. seum of Natural Sciences, Raleigh; PCL = postorbital carapace length; R = river; SR Diagnosis.—Body and eyes pigmented, = state secondary road; TCL = total cara- eyes large (X adult diam 2.4 mm, n = 11). pace length; UNC = University of North Rostrum acarinate, margins narrow, parallel Carolina; USGS = United States Geologi- to subparallel near base, slightly convex be- cal Survey; US = United States highway; tween orbits, then recurving and tapering to USNM = United States National Museum base of long acumen, which delineated by of Natural History, Smithsonian Institution, strong marginal spines; acumen comprising Washington, D. C.; and UTM = Universal 41.9 to 49.1% (X = 44.8%, n = 12) of ros- Transverse Mercator coordinates. trum length, latter comprising 31.7 to 37.9% (X = 34.4%) of TCL. Areola 2.1 to 4.2 (X = 2.9, n = 13) times as long as broad Procambarus (Ortmannicus) braswelli, and constituting 26.3 to 28.2% (X = 26.9%, new species n = 12) of TCL and 39.4 to 42.8% (X = Fig. 1 41.3%, n = 13) of PCL, and with 6 to 9 Procambarus lepidodactylus.—Hobbs, (usually 7-8) punctations across narrowest 1958a:72 (p.p.; map locality for North part. Carapace densely granulate, cephalic Carolina), 75, 76 (p.p.; southeastern section constituting 71.8 to 74.8% (X = North Carolina).—Hobbs, 1962:284 73.1%, n = 12) of TCL. Cervical spines (p.p.; southeastern North Carolina).— strong, 1 each side; cervical groove inter- VOLUME 111, NUMBER 1 83 Fig. 1. Procambarus (Ortmannicus) braswelli, new species (all from holotypic male, form I, except C, E, from morphotypic male, form II, and G, from allotypic female; setae not illustrated): A, lateral aspect of ceph- alothorax; B, C, mesial aspect of left gonopod (first pleopod); D, dorsal aspect of cephalothorax; E, F, lateral aspect of left gonopod; G, annulus ventralis and associated structures; H, epistome; I, basal podomeres of third, fourth, and fifth pereiopods; J, antennal scale; K, caudal aspect of in situ gonopods; L, M, caudomesial and caudolateral aspects, respectively, of tip of left gonopod; N, dorsal aspect of distal podomeres of right cheliped. 84 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON rupted. Branchiostegal spine strong; hepatic caudally, and with expanded base forming area with some weak tubercles. Suborbital cowl around cephalic base of central pro- angle obtuse to obsolete. Postorbital ridge jection; latter subtriangular, directed cau- moderately strong, with nearly obliterated dodistally at much greater angle than ce- groove and strong cephalic spine. Antennal phalic process; caudal element consisting scale 2.9 to 3.4 (X = 3.2, n = 13) times as of: prominent distolateral caudal knob, di- long as broad, widest proximal to mid- rected distally and delimited cephalically by length; lateral margin thickened and termi- groove; small, toothlike caudal process, nating in acute spine, mesial (lamellar) mar- originating on mesial surface of central pro- gin subangular. jection and directed caudodistally; and in- Palm of chela of cheliped 1.1 to 1.7 (X flated adventitious process, originating at = 1.4, n = 13) times wider than deep, 1.3 proximomesial base of cephalic process, ly- to 1.8 (X = 1.6, n = 13) times longer than ing wholly mesial or cephalomesial to cau- wide, and constituting 40.2 to 46.7% (X = dal process, and obscuring part of proxi- 42.5%, n = 12) of chela length; mesial mar- momesial bases of central projection and gin of palm with staggered row of 5 to 13 caudal process. small, subconical tubercles. Fingers without Annulus ventralis (Fig. 1G) symmetrical, gape, without dense setae at opposable bas- subovate, 2.4 times as wide as long, mov- es; dactyl 1.1 to 1.4 (X = 1.2, n = 13) times able; cephalic margin broadly arched, cau- length of mesial margin of palm. dal margin mildly convex and with weak Hooks on ischia of third and fourth per- caudomedian labiellum; median xh of an- eiopods of male; in form I male (Fig. II), nulus ventrally elevated, moundlike; dextral hook on third pereiopod oblique, subconi- half of mound hemitubular, C-shaped, sin- cal, overreaching