Torrenticola pearsoni Fisher & Dowling

Fisher, J. Ray, Fisher, Danielle M., Skvarla, Michael J., Nelson, Whitney A. & Dowling, Ashley P. G., 2017, Revision of torrent mites (Parasitengona, Torrenticolidae, Torrenticola) of the United States and Canada: 90 descriptions, molecular phylogenetics, and a key to species, ZooKeys 701, pp. 1-496 : 1

Torrenticola pearsoni Fisher & Dowling sp. n.

Material examined.

HOLOTYPE (♀): from USA, Arkansas, Montgomery County, Ouachita National Forest, South Fork Ouachita River, 29 Jul 2011, by AJ Radwell, & B Crump, AJR110302.

PARATYPES (7 ♀; 10 ♂): Arkansas, USA: 2 ♀ and 3 ♂ from Montgomery County, Ouachita National Forest, South Fork Ouachita River, 29 Jul 2011, by AJ Radwell, & B Crump, AJR110302 • 1 ♀ from Newton County, Buffalo National River, Mill Creek (36°3'42.12"N, 93°8'7.62"W), 30 May 2012, by TD Edwards, TDE 12-0530-004 • 1 ♀ from Newton County, Buffalo National River, Mill Creek (36°3'42.12"N, 93°8'7.62"W), 20 Jun 2012, by TD Edwards, TDE 12-0620-004 • 1 ♀ from Newton County, Ozark-St Francis National Forest, Little Buffalo River, 11 Jul 2012, by TD Edwards, TDE 12-0711-004 • Missouri, USA: 1 ♂ (ALLOTYPE) from Crawford County, Huzzah Creek, Red Bluff campground, east of Davisville, 23 Jul 2011, by IM Smith, IMS110029 • 1 ♂ from Crawford County, Huzzah Creek, Red Bluff campground, east of Davisville, 23 Jul 2011, by IM Smith, IMS110029 • 2 ♂ from McDonald County, Tiff City, beside Route 43, Buffalo Creek (36°40'17"N, 94°36'17"W), 2 May 1996, by IM Smith, IMS960004 • 1 ♀ and 1 ♂ from Oregon County, beside Route 19, north of Greer, Eleven Point (36°48'N, 91°20'W), 28 Jun 1987, by IM Smith, IMS870056 • Oklahoma, USA: 1 ♀ and 2 ♂ from Pushmataha County, beside Route 271, south of Albion, Walnut Creek (34°39'N, 95°7'W), 1 Jul 1987, by IM Smith, IMS870063A.

Type deposition.

Holotype (♀), allotype (♂), and some paratypes (4 ♀; 5 ♂) deposited in the CNC; other paratypes (3 ♀; 4 ♂) deposited in ACUA.

Diagnosis.

Torrenticola pearsoni are similar to other members of the Tricolor Complex ( T. bittikoferae , T. hoosieri , T. larvata , T. olliei , T. sierrensis , T. tricolor , T. trimaculata , T. unimaculata , T. cardia , T. kringi , T. dimorpha , and T. mohawk ) in having a short, conical rostrum. T. pearsoni can be differentiated from most other Tricolor Complex (except T. bittikoferae , T. hoosieri and T. dimorpha ) by having diffuse pink dorsal coloration, whereas most other members have bold patterning. T. pearsoni can be differentiated from T. hoosieri by having ventral extensions on the pedipalp femora and genua (lacking in T. hoosieri ) and having stockier pedipalp tibiae (length/width = 3.0-3.3 in T. pearsoni , 3.6-4.4 in T. hoosieri ). Male T. pearsoni can be differentiated from T. bittikoferae (males only) by having Dgl-4 closer to the dorsal edge (dorsal width/distance between Dgl-4 = 1.2-1.3 in T. pearsoni , 1.6-1.7 in T. bittikoferae ); more elongate pedipalp tibiae (length/width = 3.1-3.3 in T. pearsoni , 2.7-2.8 in T. bittikoferae ); and a more elongate rostrum (length/width = 2.1-2.4 in T. pearsoni , 1.8-1.9 in T. bittikoferae ). T. pearsoni can be differentiated from T. dimorpha by having an unmodified dorsal plate ( T. dimorpha has a dorsal plate medial extension covering nearly half the length of the anterio-medial platelets) and by males having unmodified pedipalps (male T. dimorpha have large, highly modified pedipalps which are expanded vertically and laterally).

Description.

Female (Figure 185) (n = 5) (holotype measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (620-730 (620) long; 455-500 (455) wide) ellipsoid with faint pink coloration without a distinct pattern. Anterio-medial platelets (123.75-142.5 (123.75) long; 62.5-70 (62.5) wide). Anterio-lateral platelets (167.5-195 (167.5) long; 70-80 (72.5) wide) free from dorsal plate. Dgl-4 much closer to the edge of the dorsum than to the muscle scars (distance between Dgl-4 365-395 (365)). Dorsal plate proportions: dorsum length/width 1.36-1.47 (1.36); dorsal width/distance between Dgl-4 1.21-1.30 (1.25); anterio-medial platelet length/width 1.93-2.04 (1.98); anterio-lateral platelet length/width 2.31-2.64 (2.31); anterio-lateral/anterio-medial length 1.34-1.42 (1.35).

Gnathosoma - Subcapitulum (247.5-290 (247.5) long (ventral); 170-210 (171) long (dorsal); 120-142.5 (120) tall) colorless. Rostrum (92.5-112.5 (92.5) long; 45-51.25 (45) wide) short and conical. Chelicerae (220-274 (221) long) with curved fangs (53-75 (64) long). Subcapitular proportions: ventral length/height 2.04-2.12 (2.06); rostrum length/width 2.06-2.25 (2.06). Pedipalps with tuberculate ventral extensions on femora and flat, flanged extensions on genua. Palpomeres: trochanter (37.5-50 (37.5) long); femur (96.25-120 (96.25) long); genu (57.5-75 (57.5) long); tibia (75-90 (75) long; 23.75-27.5 (23.75) wide); tarsus (20-25 (20) long). Palpomere proportions: femur/genu 1.60-1.69 (1.67); tibia/femur 0.70-0.80 (0.78); tibia length/width 3.00-3.27 (3.16).

Venter - (742-802.75 (743) long; 505-610 (506) wide) colorless. Gnathosomal bay (117.5-145 (132.5) long; 80-100 (80) wide). Cxgl-4 subapical. Medial suture (27.5-42.5 (30) long). Genital plates (180-187.5 (182.5) long; 147.5-155 (147.5) wide). Additional measurements: Cx-1 (235-282 (260) long (total); 130-138 (137) long (medial)); Cx-3 (335-420 (336) wide); anterior venter (180-200 (187.5) long). Ventral proportions: gnathosomal bay length/width 1.26-1.69 (1.66); anterior venter/genital field length 1.00-1.07 (1.03); anterior venter length/genital field width 1.18-1.33 (1.27); anterior venter/medial suture 4.53-6.55 (6.25).

Male (Figure 186) (n = 5) (allotypic measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (620-675 (620) long; 430-495 (430) wide) ellipsoid with faint pink coloration without a distinct pattern. Anterio-medial platelets (117.5-127.5 (117.5) long; 62.5-75 (62.5) wide). Anterio-lateral platelets (172.5-195 (188.75) long; 67.5-82.5 (70) wide) free from dorsal plate. Dgl-4 much closer to the edge of the dorsum than to the muscle scars (distance between Dgl-4 355-410 (360)). Dorsal plate proportions: dorsum length/width 1.34-1.44 (1.44); dorsal width/distance between Dgl-4 1.19-1.24 (1.19); anterio-medial platelet length/width 1.70-2.04 (1.88); anterio-lateral platelet length/width 2.36-2.70 (2.70); anterio-lateral/anterio-medial length 1.35-1.61 (1.61).

Gnathosoma - Subcapitulum (250-260 (260) long (ventral); 170-187 (186) long (dorsal); 112.5-117.5 (112.5) tall) colorless. Rostrum (92.5-102.5 (102.5) long; 42.5-46.25 (42.5) wide) short and conical. Chelicerae (225-244 (239) long) with curved fangs (55-63 (63) long). Subcapitular proportions: ventral length/height 2.20-2.31 (2.31); rostrum length/width 2.11-2.41 (2.41). Pedipalps with tuberculate ventral extensions on femora and flat, flanged extensions on genua. Palpomeres: trochanter (40-42.5 (42.5) long); femur (100-106.25 (106.25) long); genu (60-67.5 (67.5) long); tibia (75-85 (75) long; 23.75-26.25 (23.75) wide); tarsus (22.5-22.5 (22.5) long). Palpomere proportions: femur/genu 1.54-1.67 (1.57); tibia/femur 0.71-0.83 (0.71); tibia length/width 3.10-3.24 (3.16).

Venter - (720-800 (720) long; 461-588 (461) wide) colorless. Gnathosomal bay (110-130 (125) long; 70-87.5 (70) wide). Cxgl-4 subapical. Medial suture (107.5-135 (107.5) long). Genital plates (140-155 (152.5) long; 95-105 (95) wide). Additional measurements: Cx-1 (276-302 (283) long (total); 140-167 (140) long (medial)); Cx-3 (334-414 (334) wide); anterior venter (285-335 (285) long). Ventral proportions: gnathosomal bay length/width 1.26-1.79 (1.79); anterior venter/genital field length 1.87-2.18 (1.87); anterior venter length/genital field width 2.93-3.19 (3.00); anterior venter/medial suture 2.30-2.85 (2.65).

Immatures unknown.

Etymology.

Specific epithet ( pearsoni ) named in honor of Pearson Dowling, son of APGD, for his unquenchable curiosity for all things big and small.

Distribution.

Interior Highlands of Missouri and Arkansas (Figure 184).

Remarks.

Torrenticola pearsoni groups with other members of the Tricolor Complex in all analyses with high support and specimens are less than 2% different in COI sequence from each other. In the combined analysis, T. pearsoni groups with two other species ( T. hoosieri and T. projector ) with high support and these species are greater than 11% different from each other. Whereas most eastern members of the Tricolor Complex have distinctive patterns, this clade of three species contains members that lack dark patterns.

This species hypothesis is supported by low COI divergence within the species (0-2%), high divergence between species (3-15%), and the morphological characters outlined in the diagnosis.