Cambarus ocoeensis Thoma & Williams, 2025, sp. nov.

Cambarus ocoeensis sp. nov. (Figs. 1, 3, 4, 5, Table 3) Type material. OSUMC #10897 (Holotype MI), # 10898 (Allotype F), # 10896 (Morphotype MII), 10899 (Paratypes 4 MI, 3 MII, 5 F, 4 F ovig.), Tennessee, Polk Co., Rogers Branch upstream US Rt. 64 bridge, 10.7 km NW of Ducktown, 6.4 km SE of Archville 35.08286°N, 84.48927°E, RFT & Jim K. Grow, 4/15/21. Other material examined. Tennessee, Polk Co., OSUMC #8428, 1 MI, 1 M-juv, Little Caney Branch of Ocoee River east of Greasy Creek, upstream US Rt. 64, 4.3 km SW of Archville, 16.7 km NW of Ducktown, 35.09834°N, 84.54987°E, Roger F. Thoma (RFT), Lon E. Hersha (LEH), 5/25/11; OSUMC #8439, 1 MI, Right Prong Caney Creek upstream US Rt. 64, 3.9 km SSE of Archville, 15.6 km NW of Ducktown, 35.099°N, 84.53677°E, RFT & LEH, 5/26/11; OSUMC #8478, 5 MII, 5 female (F), 1 F-juv, Rogers Branch upstream US Rt. 64 bridge, 10.7 km NW of Ducktown, 6.4 km SE of Archville, 35.08286°N, 84.48927°E, RFT & LEH, 6/27/11; OSUMC #8481, 5 MII, 6 F, 1 F-juv, Gassaway Creek upstream US Rt. 64, 10.3 km NW of Ducktown, 7.1 km SE of Archville, 35.0777°N, 84.48505°E, RFT & LEH, 6/27/11; OSUMC #8483, 5 MII, 6 F, 1 M-juv, Rock Creek upstream US Rt. 64, 8.0 km NW of Ducktown, 9.2 km SE of Archville, 35.06843°N, 84.46149°E, RFT & LEH, 6/27/11; OSUMC #8486, 1 MII, 6 F, 6 m-juv, 3 F-juv, Rock Creek upstream US Rt. 64, 8.0 km NW of Ducktown, 9.2 km SE of Archville, 35.06609°N, 84.46069°E, RFT & LEH, 6/27/11; OSUMC #8496, 4 MII, 4 F, 3 M-juv, Brush Creek below US Rt. 64 bridge, 4.7 km W of Ducktown, 7.8 km NW of Copperhill, 35.0360°N, 84.4352°E, RFT & LEH, 6/28/11; OSUMC #8498, 2 MII, 4 F, 3 M-juv, 8 F-juv, unnamed tributary of Brush Creek below US Rt. 64 bridge and adjacent railroad track, 4.0 km W of Ducktown, 7.3 km NW of Copperhill, 35.03581°N, 84.42705°E, RFT & LEH, 6/28/11; OSUMC #8864, 1 F, 2 M-juv, 4 F-juv, Left Prong Caney Creek at TNDOT Corridor K Alternative 9 crossing (hike in), 3.17 km SSW of Archville, 16.81 km E of Ocoee, 35.10471°N, 84.53536°E, RFT & Max A. Luehrs, 9/19/12; OSUMC #8866, 1 MI, 5 F, 1 M-juv, 3 F-juv, Gassaway Creek upstream US Rt 64 bridge and at TNDOT Corridor K Alternative 9 crossing, 7.05 km SE of Archville, 21.91 km ESE of Ocoee, 35.07861°N, 84.48407°E, RFT & Max A. Luehrs, 9/19/12; OSUMC #8869, 3 MI, 2 MII, 2 F, 5 M-juv, 2 F-juv, Rogers Branch approx. 150 m upstream US Rt. 64 at TNDOT Corridor K Alternative 9 crossing, 6.40 km SE of Archville, 21.37 km ESE of Ocoee, 35.08329°N, 84.48845°E, RFT & Max A. Luehrs, 9/20/12. Diagnosis. Body pigmented; eyes well developed. Rostrum acuminate, with margins only slightly thickened and devoid of marginal spines or tubercles at RBMT. Carapace with areola 2.5–4.1 times as long as wide and comprising 32.4–37.2% of entire length of carapace (40.6–47.2 percent of postorbital carapace length) and bearing 5–7 punctations across narrowest part; usually 2 small cervical tubercles present, cervical spines lacking; suborbital angle acute; postorbital ridge terminating anteriorly in very small spine especially in younger specimens. Antennal scale approximately 2.2 times as long as wide, broadest at mid-length. First pereopod chela not strongly depressed, normally 1 row of tubercles along mesial margin of palm, mesial most row consisting of 6–9 (mode 8); lateral margin of palm not costate, both fingers with moderately defined longitudinal ridges dorsally, either lacking or very little lateral impression present. Male with basis of third pereiopod bearing small eminence opposing hook on ischium. First pleopod of MI with terminal elements extending slightly beyond umbo (Fig. 1F): central projection slightly tapering distally, recurved at approximately 110° to main shaft of appendage, and bearing conspicuous subapical notch; mesial process somewhat inflated, acute, and extending caudolaterally approximately equal to tip of central projection at angle of about 90° to main shaft. Female with annulus ventralis sub-symmetrical, shallowly embedded in sternum. First pleopod present. Description. Holotypic male, MI. Body subovate, depressed (Fig. 1A). Carapace maximum width greater than depth (12.1 mm). Areola 3.5 times as long as wide, moderately punctate, 5 punctations across narrowest part. Anterior section of carapace 1.9 times as long as areola, length of latter 34.6% entire length of carapace. Rostrum with slightly thickened convergent margins, devoid of marginal spines or tubercles at RBMT, tapering gradually from base to level of distal end of basal segment of antennular peduncle, from there angled at 45° and forming acute tip at median of penultimate antennomere of latter. Dorsal surface of rostrum concave, densely punctate especially basally. Postorbital ridge short, not strongly elevated, grooved dorsolateral, and terminating without tubercle. Subrostral ridge moderately developed. Suborbital angle obtuse. Branchiostegal spine very small. No cervical spine, replaced by 1 weak tubercle, one other smaller tubercle dorsal. Carapace punctate dorsally, with polished area in gastric region, and granulate laterally; granules largest on hepatic region and in anteroventral branchiostegal region. Abdomen as long as carapace (28.7 and 28.6 mm), narrower than thorax (12.9 and 14.5 mm, respectively); pleura 3–5 of moderate length, straight ventrally and with caudoventral extremity formed by 90° slightly rounded angle. Telson anterior section with 2 spines in each caudolateral corner. Uropodal protopod with distal spine on each lobe; mesial ramus with weak sub-median ridge terminating in short pre-marginal spine. Epistome anteromedian lobe (Fig. 1H) subtriangular with rounded edges, anterolateral margins thickened; main body with shallow median fovea; epistomal zygoma moderately arched. Antennule with ventral surface of proximal antennomere with minute spine at base of distal one-third. Antennal peduncle with minute spine on lateral surface of basis and lacking tubercle on ventral surface of ischium; antennal scale (Fig. 1E) approximately 2.6 times as long as wide, broadest at mid length, its mesial margin rounded, lacking angles, and its distal spine reaching end of ultimate antennomere of antennular peduncle. Third maxilliped with ventral surface of ischium with clusters of long stiff setae throughout and submarginal lateral row of equal size; distolateral extremity angular. Right chela (Fig. 1I) about 2.2 times as long as broad; mesial margin of palm constituting 29% total length, with row of 6 tubercles subtended dorsally by another row of 5: on palm otherwise punctate, without other tubercles. Both fingers with moderately developed dorsal sub-median longitudinal ridges, flanked by setiferous punctations. Fixed finger not costate laterally; opposable margin of finger, from base, with 2 small, 1 large, 2 small, 1 larger, and 2 very small tubercles. Narrow band of minute denticles extending distally from level of sixth tubercle to corneous tip of finger. Opposable margin of dactyl, from base, with 1 larger, 2 smaller, 1 slightly larger, and 6 smaller tubercles decreasing in size. Single row of minute denticles extending distally from sixth tubercle from base; mesial margin of dactyl tuberculate along proximal one-third and bearing row of setiferous punctations along distal two-thirds. Carpus with moderately deep, slightly oblique longitudinal furrow running dorsal full length, flanked by punctations; mesial surface with prominent spine near distal third and smaller spine proximally, larger spine lacking additional small tubercle at proximoventral base; ventral surface with 1 tubercle on distal margin. Merus with 2 subdistal tubercles dorsally, mesial and lateral surface smooth, ventromesial row of 9 spinose tubercles and ventrolateral margin with 2. Mesial margin of ischium with row of 4 small spinous tubercles. Third pereiopod ischium with simple hook, overreaching basioischial articulation, opposed by small eminence on basis (Fig. 1G). Fourth pereiopod coxa with vertically disposed caudomesial boss; that of fifth without boss, its ventral surface membranous. First pleopods (Fig. 1B, C) contiguous at bases and reaching coxae of third pereiopods; both terminal elements recurved at angle greater than 90° to main shaft. Mesial process inflated, quickly tapering distally to acute tip directed caudolaterally, upturned at end; central projection, widest at base, more strongly recurved than mesial process and with moderate subapical notch. Allotypic female. Differing from holotype, other than in secondary sexual characters, as follows: chela 75% of carapace length; mesial margin of palm of left chela with 8 tubercles in mesial most row subtended dorsolaterally by row of 4 very small tubercles; opposable margin of fixed finger with 3 smaller tubercles at base, opposable margin of dactyl with row of 10 similar sized tubercles decreasing in size distally; ventral surface of merus with lateral row of 3 spinous tubercles. Antennal scale length 2.1 times width. Eye diameter 46% of rostrum width at level of eyes. Abdomen width 74% of length. Annulus ventralis (Fig. 1F) rather shallowly situated in sternum, asymmetrical, tongue running from right to left, with left side more rounded than right, width 86% of length; anterior half with median longitudinal furrow flanked by paired narrow ridges, and prominent subangular ridge forming caudal wall; sinus originating in caudal portion of median furrow, and, extending caudally for short distance, turning sinistrally at right angle before making hairpin turn and crossing to dextral side of median line; from there sinus curving caudally in gentle arc across caudal ridge and terminating on caudal face of latter almost on median line. Postannular sclerite slightly more than half width of annulus and about one-third as wide as long; surface without ornamentation. First pleopod extending anteriorly to anterior margin of annulus when abdomen flexed. Morphotypic male, Mll. Differing from holotype in following respects: areola wi