Cambarus (Cambarus) bartoniicavatus Hay, 1902

Loughman, Zachary J. & Simon, Thomas P., 2011, Zoogeography, taxonomy, and conservation of West Virginia's Ohio River floodplain crayfishes (Decapoda, Cambaridae), ZooKeys 74, pp. 1-78 : 11-15

Cambarus (Cambarus) bartoniicavatus Hay, 1902

Cambarus bartonii cavatus Hay 1902:435. Faxon 1914:425. Taylor et al. 1996:29. Taylor et al. 2007.

Cambarus (Bartonius) bartonii Ortmann 1905b:120 [in part].

Cambarus (Cambarus) bartoni cavatus Ortmann 1931:127.

Cambarus (Cambarus) bartonii cavatus Fowler 1912:341. Hobbs, 1969:109, fig. 5; 1974:11, fig. 25; 1989:14, fig. 31. Jezerinac et al. 1995:84, fig. 39 A– 39H. Taylor and Schuster 2004:63, figs. 32, 33 A– 33H.

Diagnosis.

Rostrum broad; margins reduced, subparallel, terminating cephalically in a gentle angle to form acumen; anterior region of rostrum excavated; acumen consisting of a single upturned spiniform tubercle; postorbital ridges truncated, cephalic margin with weak tubercle; cephalothorax oval shaped and slightly dorsoventrally flattened in profile; 2-3 punctations across narrowest region of areola; branchiostegal region moderately punctate, with small tubercles; chelae broad and robust; mesial surface of palm consisting of two rows of defined tubercles; first row with 5-8 rounded tubercles; second with 3-4 tubercles; two prominent subpalmar tubercles present; first form gonopods contiguous at base, with 2 terminal elements bent 90° to the base; central projection with shallow subapical notch; total length of central projection equal to mesial process length; second form gonopod non-corneous and blunt; mesial process bulbous, truncating distally; annulus ventralis rhomboid in shape, embedded shallowly in sternum and movable.

Color in life.

Carapace dorsally olivaceous brown, beige, or tan; rostrum margins chestnut brown to brown; chelae olivaceous green to brown; dactyl and propodus denticles cream or yellow; pereiopods tan, light green, cream, or gray; abdomen terga dorsally brown or beige, bordered in gray; ventral surfaces cream or white.

Specimens examined.

Cambarus bartonii cavatus were collected from six counties at 15 locations. Collection locales and demographics are listed below.

JACKSON COUNTY: Flooded field adjacent to RT 33 S, 9.72 air km (6.04 mi) N of Ravenswood, 39.04274 -81.7827; 3 April 2005 - (WLU 05040301), 3♀. Little Sandy Creek, at intersection of RT 68/CR 8, 38.991497 -81.761765; 21 July 2006 - (WLU 06012103), 1 II ♂. Vernal pool complex adjacent to railroad tracks 3.56 km (2.21 mi) N of Ravenswood, 39.09015 -81.79469; 3 April 2005 - (WLU 05040302), 1♀. West Creek, at intersection of CR 12 / CR 10, 38.924362 -81.94200; 20 July 2006 - (WLU 06072001), 1 II ♂, 1♀. MASON COUNTY: Pin oak swamp adjacent to Point Pleasant Moose Lodge in Wagner, 38.833603 -82.12227; 6 June 2005 - (WLU 05060601), 2 ♀. Roadside ditch adjacent to RT 2, 9.17 km (5.7 mi) S of Point Pleasant, 38.80469 -82.18821; 4 March 2005 - (WLU 05030401), 2 I♂, 1 ♀. Roadside ditch adjacent to RT 2 N, 2.91 km (1.81 mi) N of Clover, 38.589428 -82.19548; 4 March 2005 - (WLU 05030402), 1 ♀. Roadside ditch adjacent to RT 2 N, 1.93 km (1.2 mi) N of Glenwood, 38.58816 -82.201004; 3 April 2005 - (WLU 05040305), 1 I♂, 2 ♀. Roadside ditch adjacent to RT 2 N 0.90 air km (0.56 mi.) N of Hogsett, 38.70056 -82.17708; 17 March 2005 - (WLU 05031707), 1 ♀. PLEASANTS COUNTY: Middle Island Creek at RT 2 crossing, 39.40328 -81.197624; 21 July 2006 - (WLU 06072104), 1 ♀. TYLER COUNTY: Nameless tributary at RT 2 crossing in Friendly, 39.513386 -81.06285; 28 July 2005 - (WLU 05072806), 1 I♂, 1 ♀. WETZEL COUNTY: Doolins Run at RT 2 crossing, 39.639576 -80.85607; 28 July 2005 - (WLU 05072805), 1 II♂. WOOD COUNTY: Big Run at CR 21-1 crossing, 39.364048 -81.45656; 21 July 2004 - (WLU 06072101), 1 ♀. Boaz Swamp Wildlife Management Area, 39.462868 -81.10855; 12 April 2004 - (WLU 04042101), 1 ♀. Nameless tributary crossing 3.54 km (2.2 mi) S of Parkersburg, 39.05142 -81.742836; 21 July 2006 - (WLU 06072106) 1 II♂, 1 ♀.

Distribution.

Cambarus bartonii cavatus ranges from northern Georgia and Tennessee through eastern Kentucky, east central Ohio and western Virginia ( Taylor and Schuster 2004). In West Virginia Cambarus bartonii cavatus is prevalent throughout basins associated with the lower reaches of the Kanawha system west of Kanawha Falls and basins draining into the Big Sandy River system. Cambarus bartonii cavatus floodplain populations inhabit the Middle Ohio North, Middle Ohio South, and Lower Ohio basins, and are the dominant secondary burrowing species inhabiting the floodplain (Figure 6). It is replaced in the Middle Ohio North basin in Proctor Creek with Cambarus carinirostris . A specimen collected from Doolin Run, Wetzel County, a tributary to Fishing Creek, represents the northernmost collection of this species in West Virginia. The distribution of this species has not changed since Jezerinac et al.'s (1995) survey in the late 1980's.

Morphometrics.

Cambarus bartonii cavatus is a medium to large crayfish. The largest individual collected was a female with a 51.6 mm TCL taken from an ephemeral pool complex 3.6 km north of Ravenswood, Jackson County. The largest male collected was a form I collected from a roadside ditch 1.9 km north of Glenwood, Mason County, with a TCL of 45.6 mm. Mean Cambarus bartonii cavatus carapace length was 34.4 mm (n = 25, SE = 12.42). Morphometric data for Cambarus bartonii cavatus is presented in Table 4.

Habitat and natural history.

Cambarus bartonii cavatus (Figure 8) is a secondary burrowing species like Cambarus carinirostris , ( Jezerinac et al. 1995). Along the floodplain, it utilized first and second order stream habitats, ephemeral wetlands, and roadside ditches (Figure 9). The species demonstrated a preference for roadside ditches, with 42.1% of individuals taken from this habitat. Ditches with an associated first-order stream produced particularly robust populations.

Within lotic systems, Cambarus bartonii cavatus prefers first through third order streams to larger streams. It burrows extensively in stream banks, particularly those composed of hardpan and similar regoliths. Burrows are intricate, with central shafts ranging in depth from 0.3 m to 1.0 m. At the terminus of the central shaft, enlarged chambers were always present with several branching auxiliary tunnels. One marked difference between Cambarus bartonii cavatus burrows and those of other burrowing species is the width of the central shaft and the dimensions of the central resting chamber.

The central shaft and central chamber of other floodplain burrowing species (e.g., Cambarus thomai Jezerinac, 1993, Fallicambarus fodiens (Cottle, 1863), were the width of the crayfish’s carapace at the widest point. Cambarus bartonii cavatus burrows did not follow this same pattern and, usually, were wide and oblong. Anecdotally, Cambarus bartonii cavatus burrows were readily identified by the presence of these structural components, but this method of identification was not used to definitively verify Cambarus bartonii cavatus presence at a site.

In late winter females comprised 66% of trap captures. Those captured in late winter/early spring all possessed active glair glands. This condition has been used in previous studies to indicate future egg extrusion and is likely the explanation for this increase in female activity ( Hobbs 1981). No ovigerous females were collected during this study. Jezerinac et al. (1995) reported ovigerous specimens in West Virginia in July. A female retained in captivity collected in a roadside ditch 2.91 km north of Clover extruded eggs on 18 May 2005. Males captured in late winter/early spring did not show any trend toward any single demographic group, with an equal number of form I and form II individuals captured. Crayfish associates collected with Cambarus bartonii cavatus included Cambarus robustus , Cambarus thomai , Fallicambarus fodiens , Orconectes obscurus , Orconectes sanbornii (Faxon, 1884), Orconectes virilis and Procambarus acutus . Seasonal data for Cambarus bartonii cavatus are presented in Table 3.

Conservation status within study area.

Cambarus bartonii cavatus populations along the floodplain are stable and do not warrant special attention.