Cambarus fetzneri, Loughman & Welsh & Thoma, 2019

Loughman, Zachary J., Welsh, Stuart A. & Thoma, Roger F., 2019, Cambarus fetzneri sp. nov., a new species of burrowing crayfish (Decapoda: Cambaridae) from the Allegheny Mountains of Virginia and West Virginia, USA, Zootaxa 4651 (1), pp. 38-50 : 38-50

publication ID	https://doi.org/ 10.11646/zootaxa.4651.1.2
publication LSID	lsid:zoobank.org:pub:546982E1-067E-4963-8066-41F70D518A1F
persistent identifier	https://treatment.plazi.org/id/03D38797-2248-FFB4-FF71-FD51FAA59313
treatment provided by	Plazi
scientific name	Cambarus fetzneri
status	sp. nov.

Treatment

Cambarus fetzneri View in CoL sp. nov. Loughman, Welsh & Thoma, sp. nov.

Figures 1–5 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 , Table 1 View TABLE 1

Diagnosis. Body and eyes pigmented. Rostrum sub-rectangular and broad, weakly excavated, and ventrally deflect- ed anteriorly, rostral margins pronounced and entire to acumen, and sub-parallel; converging to acumen. Acumen short with prominent dorsally deflected tubercle at terminus. Areola 2.3–5.8 (ẍ = 3.8, n = 27, σ = 0.8) times as long as wide and obliterated at middle; open anteriorly and posteriorly. Lateral portion of branchiostegal region of carapace heavily punctate; cervical spines and tubercles absent. Branchiostegal basipodite, and ischiopodite spines and tubercles absent. Postorbital ridge lacking terminating spines or tubercles. Suborbital angle subacute. TCL 1.9–2.2 (ẍ = 2.0, n = 27, σ = 0.2) times greater than width.

Form I and II males possessing hook on ischium of third pereopod only; hook gently curved at apex, overarching basioischial joint in form I males, not reaching basioischial joint in form II males; hook not opposed by tubercle on third pereopod basis.

Mesial surface of palm of chela possessing one, rarely two rows of tubercles; first row consisting of 2–6 tubercles; second row 2–4. Subpalmar tubercles absent. Dorsomedian ridge of fixed finger of propodus pronounced. Weak to no lateral impression at base of fixed finger. Chelae palm punctate. Dactyl possessing strong dorsalongitudinal ridges, lacking pronounced tubercles. Propodus possessing enlarged tooth at midlength. Dactyl possessing weak notch midlength to junction of the dactyl with the propodus. Dactyl and fixed finger each with sharp corneous terminal tip. Form I male palm length constituting 82.5–114.5% (ẍ = 92.7, n = 9, σ = 2.8) of palm width and 41.6– 45.3% (ẍ = 43.5, n = 9, σ = 1.2) of total propodus length; female dactyl length 38.9–47.7% (ẍ = 43.1, n = 6, σ = 3.6) of total propodus length. Ventral lateral margin of merus with three enlarged spines; ventralmesial margin with 6–8 smaller spines. Single to 3 carpal spine present on dorsal surface. Ventral surface of carpus possessing tubercles.

Gonopod of form I male with long terminal elements. Central projection sickle shaped and not tapering distally; recurved> 90º to main shaft of gonopod, possessing subapical notch. Mesial process directed approximately 90° to shaft; tapering to a point distinctly caudal to to terminance of central projection; and not projecting beyond gonopod umbo.Annulus ventralis immovable; distinctly asymmetrical caudally; cephalic portion with median trough leading to strongly sculptured central fossa; exaggerated “S” bend in sinus terminating at caudal edge.

Holotypic, form I ( Fig. 2 View FIGURE 2 A–C, H–J?). Body lightly compressed dorsolaterally; thoracic section of carapace slightly wider than abdomen and cephalic section of carapace. Carapace height slightly less than carapace width (11.1 and 11.4 mm, respectively). TCL 23.4 mm; PCL 20.7 mm. Areola 9.5 times longer than wide, with 0 punctations across narrowest part; length of areola 40.6% of TCL (45.9% of PCL). Rostrum wide and subrectangular with broad acumen and weakly excavated equally along length; margins thickened and converging caudal to acumen ( Fig. 2G View FIGURE 2 ). Rostrum 1.3 times longer than wide. Postorbital ridges moderate in length, lacking terminating spines or tubercles. Suborbital angle subacute ( Fig. 2A View FIGURE 2 ). Lacking cervical spine or tubercles; mandibular, branchiostegal, and orbital regions of carapace tuberculated; greatest tubercle density in hepatic region. Tubercles in the hepatic region prominent and well developed.

Abdomen slightly shorter than carapace, pleura rounded cephaloventrally, angled caudoventrally. Cephalic section of telson with 1 large spine in each caudolateral corner. Proximal podomere of uropod with 2 distolateral spines on mesial lobe; median spine, originating from ventral surface; mesial ramus of uropod with median ridge ending distally in distomedian spine not overreaching margin of ramus. Distal margin of proximal segment of lateral ramus of right uropod bearing 9 immovable, small spines.

Cephalomedian lobe of epistome subtriangular, forming strong angle at junction with endostyle; cephalolateral margins not thickened ( Fig. 2J View FIGURE 2 ); main body possessing weak cephalomedian fovea.

Antennal scale broadest distally; lateral margin thickened, terminating in very large corneous spine, angled at 45°; setiferous mesial margin. Right antennal scale 2.9 mm long, 1.1 mm wide. Tip of right antenna reaching middle of telson when adpressed.

Mesial surface of right chela palm with single row of 6 well-defined tubercles ( Fig. 2I View FIGURE 2 ). Palm length 78.5% of palm width; depth of palm 5.1 mm. Ventral surface of palm lacking tubercles. Dorsal longitudinal ridge of dactyl well developed ( Fig. 2I View FIGURE 2 ); dactyl terminating in large corneous spine. Dorsomedian ridge of propodus fixed finger developed with weak lateral impression at junction of fixed finger and palm. Single prominent large tubercle on propodus and dactyl at mid length of both structures. Dactyl possess a weak notch ( Fig 2I View FIGURE 2 ). Fixed finger of propodus with sharp, corneous tip. Carpus with prominent dorsal furrow ( Fig. 2I View FIGURE 2 ), ventrolateral surface covered with setiferous punctations; mesial margin with large, procurved spine at mid-length, second spine posterior to previous spine. Distodorsal surface of merus with single, large spiniform tubercle; 3 large spines on ventrolateral surface. Hook on ischium of third pereopod only; gently curved at apex, overarching basioischial joint, not opposed by tubercle on base. Form I gonopod with subapical notch; central projection length not to distal portion of mesial process ( Fig 2 View FIGURE 2 B–C).

Allotypic female ( Fig. 2F View FIGURE 2 , Table 1 View TABLE 1 ). Differing from holotype in following respects; carapace height equal to carapace width (11.1 and 11.1 mm, respectively); TCL 24.2 mm, PCL 21.1 mm. Areola length 37.6% of TCL (43.1% of PCL). Mesial surface of chelae with single row of 5 tubercles. Palm length (5.9 mm) 71.1% of palm width (8.3 mm);. All measurements and counts from right chela. Antennal scale 2.6 mm long, 1.2 mm wide. Annulus ventralis as described in diagnosis ( Fig. 2F View FIGURE 2 ); width of postannular sclerite half total width of annulus ventralis; first pleopods uniramous, reaching central region of annulus ventralis when abdomen flexed.

Morphotypic male, form II ( Fig. 2 View FIGURE 2 D–E, Table 1 View TABLE 1 ). Differing from holotype in the following respects: Carapace height less than carapace width (9.4 and 9.5 mm respectively); TCL 21.7 mm and PCL 18.6 mm. Areola length 38.7% of TCL (44.9% of PCL). Rostrum broad and margins entire; rostrum ventrally deflected and excavated; rostrum 1.9 times as long as wide. Abdomen 21.2 mm long. Mesial margin of palm of cheliped with single row of 6 tubercles. Palm length (5.2 mm) 80.0% of palm width (6.5 mm). All measurements and counts from right chela. Antennal scale 2.9 mm long, 1.2 mm wide. Gonopods reaching anterior margin of 4 th pereopod caudomesial boss. Central projection curved 90° to shaft ( Fig. 2 View FIGURE 2 D–E). Hook on ischium of third pereopod small, not reaching basioischial joint.

Size. Form I male (n = 6) TCL ranges in size from 20.8–23.2 mm (18.2–20.3 mm PCL) with a mean TCL of 19.6 mm. Mean TCL of form II male (n = 9) is 21.4 mm, ranging in size from 19.6–23.7 mm (PCL 17.5–21.1 mm). Female (n = 18) mean TCL is 24.7 mm and ranges from 19.3–29.7 mm (PCL 17.4–25.9 mm). The largest specimen examined was a female with a TCL of 29.7 mm (PCL 25.9 mm).

Color. Carapace ground color of C. fetzneri sp. nov. ( Fig. 3 View FIGURE 3 ) light blue to cobalt blue; posterior margin of carapace same as ground color, without saddle. Hepatic and antennal region of carapace with light blue to white punctations. Postorbital ridge darker blue than blue on carapace. Rostrum margins and acumen light blue to blue. Cephalic section of carapace immediately anterior to and including cervical groove blue; mandibular abductor scars mottled, ranging from light-blue, to dark-blue. Lateral margin of antennal scale blue; body of antennal scale light blue to cream. Antennal flagellum and antennules blue; dorsal surface of lamellae blue; ventral surface light-blue to blue. Dorsal surface of chelae cobalt blue, blue to dark blue, with occasional light blue highlights. Denticles on opposable surfaces of fingers white, or cream. Mesial margin of palm highlighted with white to cream tubercles; single large white knob on propodus at junction with dactyl; ventral surface of chelae white or cream. Dorsal surface of carpus blue or dark blue; region adjacent to and including furrow blue; carpus spine white or cream. Merus blue. Podomeres of pereopods blue, light blue, or dark blue; joints of pereopod podomeres cream. Dorsal and dorsolateral surface of abdomen same colors as carapace; tergal margins blue, white, or cream; abdomen lacking dorsal stripe.

Uropods same colors as abdomen. Ventral surface of abdomen and carapace cream. Dorsal ridge of form I gonopod central projection amber; body of central projection, gonopod, and mesial process tan. Form II gonopod and all associated processes cream. Cephalic portion of annulus ventralis cream; ridge of fossa pink; caudal region of annulus ventralis ranges from pink to cream colored. In essence, this crayfish is blue ( Fig. 4 View FIGURE 4 ).

Type locality. Ditches along railroad tracks in Bemis, Randolph County, West Virginia, N 38.8094 W -79.7404. The type location is composed of several wet ditches with ephemeral water sources which run adjacent to a high wall cut into the hillside. Allegheny Birch ( Betula alleghaniensis ), Eastern Hemlock ( Tsuga canadensis ), and various maple ( Acer spp.) species constitute the mesophythic forest where the type series was collected. The water table is perched at the type location, and C. fetzneri sp. nov. burrows occur primarily adjacent to the high wall cut. Burrows here are of the colonial type, and merge into a large series of shallow tunnels with resting chambers and several burrow portals. Cambarus fetzneri sp. nov. is readily collected here by burrow excavation or flipping stones above burrow networks. The type series was collected by Gregory Myers on 14 July, 2017.

Disposition of types. The holotype, allotype, and morphotype are deposited in the Carnegie Museum of Natural History (catalog numbers CMNH 38951 , 38952 , 38953 , respectively). Paratypes, 1 MI and 1 F, are deposited in each of the following: the North Carolina state Museum, ( NCSM 90120 , 90121 ), the Ohio State Museum of Zoology ( OSUMC 10858 ).

Range and specimens examined. Cambarus fetzneri sp. nov. is limited to the Allegheny Mountains and western Ridge and Valley physiographic provinces in Virginia and West Virginia at elevations above 1,800 feet (550 m), where it occurs in one Virginia and six West Virginia, Counties ( Fig 4 View FIGURE 4 ). It has been observed by RFT (1978) that mountain C. monongalensis , which now subscribes to C. fetzneri sp. nov. could occur in Garett County Maryland, specifically in the region of Swallow Falls State Park. No vouched specimens were collected by RFT so validation remains to be established, and it is possible that the animals in question was introduced. Within this region C. dubius is prevalent, and presently occupies all habitat that C. fetzneri would occur in ( Loughman 2010). Recent collecting efforts have failed to find C. fetzneri .

We examined 33 C. fetzneri sp. nov. (6 form I males, 7 form II males, and 20 females) from a total of 28 sites. This species is highly sought by collectors, and it is known that over collection for the pet trade has resulted in the destruction of once thriving colonies. As such, collections locales are not being presented in this publication, but are available to researchers via an information request from the West Virginia Division of Natural Resources Wildlife Resources Unit research unit and the Virginia Department of Game and Inland Fisheries.

Habitat and life history notes. Cambarus fetzneri sp. nov. is a montane primary burrowing crayfish that frequents seepage wetlands, springs, roadside ditches and residential yards in the Allegheny Mountain and western Ridge and Valley region of central Virginia and West Virginia. Red Spruce ( Picea rubens ) forests, as well as Allegheny Birch, Eastern Hemlock, forests are specific communities that C. fetzneri sp. nov. often frequents. Several species of salamanders, anurans, and a myriad of invertebrate taxa utilize C. fetzneri sp. nov. burrows as refugia, especially during periods of heat and drawdown, making this crayfish both an important keystone species and ecosystem engineer for the Allegheny Mountain region.

Two distinct types of burrows are created by C. fetzneri dependent on the ecological situation the species is encountered in. In situations where suitable habitat is limited, C. fetzneri sp. nov. constructs burrows whose morphology is consistent with other montane burrowing species, such as C. dubius or C. deweesae , that are occupied by a single animal. Burrow architecture normally consists of a portal and a central shaft leading to an enlarged resting chamber (0.2 to 1.0 m underground). Further, burrows can be complex, with multiple ancillary tunnels leading from the resting chamber, ramifying in multiple directions. Our observations and those of Jezerinac et al. (1995) documented leaves and other vegetation (with evidence of mastication) within the resting chamber. Excavation of burrows regularly results in the capture of juveniles and young of the year, especially when adult females are encountered.

In large seepage wetlands and springs, several C. fetzneri sp. nov. will occupy the same burrow network, with ancillary tunnels radiating into multiple resting chambers, each possessing central shafts extending to surface portals. In these situations, C. fetzneri sp. nov. resting chambers usually occur 0.1 to 0.5 m underground and are not as deep as the previously mentioned morphology. Cambarus fetzneri sp. nov. are encountered throughout the network, and often together. In addition to crayfish, masticated leaves and twigs are also encountered throughout the network, in both ancillary tunnels and resting chambers specifically. Females outnumber males in these “colonial” burrows, and several size cohorts occur throughout the network as well. Jezerinac et al. (1995) also encountered more females than males when sampling C. fetzneri sp. nov., though they noted sampling smaller burrows resulted in the capture of additional males. Networks can encompass the entirety of seeps and springs, and can take up as much as 10m 2.

Cambarus fetzneri sp. nov. is frequently encountered moving above ground across the forest floor following periods of precipitation and during seasons with high relative humidity. Surface activity occurs primarily in early morning and during evening hours, though encounters occur during afternoon hours on overcast, misty days (Thomas K. Pauley, Marshall University, Pers. Com.). Though surface activity has been noted for North American burrowing crayfish species, C. fetzneri sp. nov. does appear to be more active on the surface than most burrowing crayfishes. When burrows become inundated by precipitation and groundwater levels rise, C. fetzneri can also be observed in ephemeral pools and roadside ditches at the mouths of their flooded burrows, especially after dark (Z. J. Loughman pers. Obs.).

Form I males have been collected in April through December, and likely occur during all months of the year. Form II males have also been collected during these same months. Females with glair have been collected in September, and again in April through June. Collection of ovigerous females has occurred July through September, and interestingly, ovigerous females have been encountered several times traversing the surface far from any notable water source. Cambarus fetzneri sp. nov. egg compliments are notably smaller than most epigean Cambarus species, though similar in number to members of the C. dubius complex that have received life history treatments ( Loughman 2010). As mentioned previously, young of the year and juveniles are encountered in burrows, especially in situations where individual burrow networks merge into other networks during all months that C. fetzneri sp. nov. has been collected.

Conservation status. C ambarus fetzneri sp. nov. should be listed as currently stable based on the criteria of the American Fisheries Society established in Taylor et al. (2007), assigned a G4/G5 ranking using the global conservation criteria of Master (1991), and listed as least concern (LC) using the criteria of the International Union for the Conservation of Nature ( IUCN 2001). At present, C. fetzneri sp. nov. is common to locally abundant throughout its distribution in West Virginia, though limited to a few known sites in Virginia. Virginia sites represent the eastern extent of the distribution range of C. fetzneri sp. nov., which could explain the lack of populations. RFT ( Fetzner and Thoma 2014) completed surveys in Virginia for C. fetzneri sp. nov. and suggested that C. fetzneri sp. nov. be considered for state listing as a rare species (S1). We agree with his findings, and believe Virginia populations warrant protection. West Virginia populations are protected by land use practices associated with the Monongahela National Forest, Dolly Sods Wilderness, and Canaan Valley National Wildlife Refuge, which collectively encompasses the bulk of C. fetzneri sp. nov. distribution within the state. Threats exists for populations outside of these protected lands, particularly from development of natural gas plays, timbering, and urban development. It is our suggestion that C. fetzneri sp. nov. be listed as S 3 in West Virginia given that the majority (>90%) of the species’ total global distribution fall within West Virginia’s borders.

Crayfish associates. Cambarus fetzneri sp. nov. is most frequently collected with Cambarus carinirostris Hay 1914 , which often burrow adjacent and occur in stream channels near preferred, forested seep habitats of C. fetzneri sp. nov. Jezerinac et al. (1995) reported C. fetzneri sp. nov. occurring syntopically with C. dubius , another primary burrowing species at a single locality, and we have collected Lacunicambarus thomai ( Jezerinac 1993) at a single location alongside C. fetzneri sp. nov. Tertiary burrowing species collected in streams adjacent to C. fetzneri sp. nov. include Cambarus appalachiensis Loughman, Thoma, and Welsh 2017 , Cambarus chasmodactylus James 1966 , Cambarus elkensis Jezerinac and Stocker 1993 , Cambarus smilax Loughman, Simon, and Welsh 2011 , Faxonius obscurus ( Hagen, 1870) , and invasive Faxonius virilis (1870) .

Variation. Morphologically C. fetzneri sp. nov. is homoplasic, demonstrating little population differences across its range. Animals from Nicholas County, West Virginia demonstrated the most variation, and possess an incomplete second row of two to four tubercles. Interpopulation differences exist in the dominance of blue coloration, with some populations being muted, and others being brighter. Distal dactyl and propodus colorations range from orange in most populations to vivid red in more southern populations. Juveniles often appear more greyish blue than the more vividly colored adults.

Relationships and comparisons. Cambarus fetzneri sp. nov. is most similar, within the genus, to members of the C. dubius complex, and C. monongalensis . Among members of the C. dubius complex, Cambarus pauleyi and Cambarus loughmani ; occur in the central Appalachians of West Virginia and are blue. Both species are quickly demarcated from C. fetzneri sp. nov. by the costate ridge along the ventral margin of the propodus. Cambarus fetzneri sp. nov. lacks this ridge, and has an entire ventral margin to the propodus. Both C. loughmani and C. pauleyi also reach a larger adult size than C. fetzneri sp. nov. and neither occur within the geographic range of C. fetzneri sp. nov.

Cambarus fetzneri sp. nov. differs from C. monongalensis in adult size, coloration, and several meristic ratios. Compared to C. monongalensis , C. fetzneri sp. nov. are significantly smaller as adults (ẍ = 23.3, n = 33), compared to C. monongalensis (ẍ = 28.1, n = 32,). Though body pigments in both species are dominated by blues, the amount of blue in specific body regions can be used as diagnostic characters to separate these species. Cambarus fetzneri sp. nov. rostrum margins are blue, and occasionally highlighted in light blue or cream ( Fig. 5 View FIGURE 5 ). Cambarus monongalensis rostral margins are maroon to cherry red, and only rarely blue ( Fig. 5 View FIGURE 5 ). When they are blue, they are always darker blue than the rest of the rostrum, and often take on a purplish hue.

Chelae coloration in life can also be used to differentiate these species. The chelae of Cambarus fetzneri sp. nov. have reddish, orange, or light brown coloration only at the extreme distal tips of the dactyl and the propodus ( Fig. 5 View FIGURE 5 ). Cambarus monongalensis have red, orange or light brown coloration that extends anywhere from 10 to 33% from the distal tip towards the junction of the dactyl and the propodus ( Fig. 5 View FIGURE 5 ). Rostrum and acumen ratios can also be used to separate C. fetzneri sp. nov. from C. monongalensis . Cambarus fetzneri sp. nov. have narrower, shorter rostrums compared to C. monongalensis , which have wider, longer rostrums. Cambarus fetzneri sp. nov. chelae are also notably more subrectangular than C. monongalensis , which have more ovoid, elongate chelae. Jezerinac et al. (1995) also noted that differences in the number and shape of the spines on the carpus exist between what ultimately would be C. fetzneri sp. nov. when compared to C. monongalensis . We too observed this difference, with C. fetzneri sp. nov. having more carpus spines compared to C. monongalensis in most cases. Unfortunately, as reported by Jezerinac et al. (1995), this character is somewhat plastic, and considerable overlap does exist between some C. fetzneri sp. nov. populations and C. monongalensis .

Common name. The Allegheny Mountain Mudbug.

Etymology. The species epithet fetzneri is the Latinized form of Fetzner, in honor of former International Association of Astacology president, Editor of Freshwater Crayfish, and Carnegie Museum Associate Curator of Crustaceans, Dr. James Fetzner Jr.. Jim’s genetics work was critical to the recognition of the “mountain” form of C. monongalensis as a distinct species, and as such it is only fitting that the species bare his name. All of us have collaborated with Jim on several projects, consider him a dear friend, and know him to be an incredibly resolute and precise scientist. Dr. Fetzner’s genetics work on other projects has resulted in the recognition of several new crayfish species, and his contributions to North American astacology are many, and make him worthy of this honor.