Torrenticola mulleni 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 mulleni Fisher & Dowling sp. n.

Material examined.

HOLOTYPE (♀): from USA, Wyoming, Fremont County, Wind River Mountains, Sinks Canyon, Popo Agie River, south of Lander, 1 Aug 2012, by IM Smith, IMS120049, DNA 2928.

PARATYPES (6 ♀; 5 ♂): Idaho, USA: 1 ♀ from Blaine County, Little Wood River (43°29'51"N, 114°3'28"W), 27 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0727-001 • 1 ♂ from Custer County, Morgan Creek (44°39'20"N, 114°12'56"W), 31 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0731-004 • Montana, USA: 1 ♀ and 1 ♂ from Ravalli County, Bitterroot National Forest, East Fork Bitterroot River (45°51'40"N, 114°1'46"W), 3 Aug 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0803-005 • 1 ♀ and 1 ♂ from Missoula County, Lolo National Forest, off 12, Lolo Creek (46°46'7"N, 114°27'53"W), 7 Aug 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0807-003 • Utah, USA: 1 ♀ from Summit County, Wasatch-Cache National Forest, Slate Creek (40°37'45"N, 111°11'46"W), 23 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0723-006 • 1 ♂ from Wasatch County, Wasatch-Cache National Forest, Provo River (40°35'37"N, 111°5'43"W), 23 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0723-001 • Wyoming, USA: 1 ♂ (ALLOTYPE) from Fremont County, Wind River Mountains, Sinks Canyon, Popo Agie River, south of Lander, 1 Aug 2012, by IM Smith, IMS120049, DNA 2929 • 1 ♀ from Fremont County, Wind River Mountains, Sinks Canyon, Popo Agie River, south of Lander, 1 Aug 2012, by IM Smith, IMS120049 • 1 ♀ from Johnson County, Bighorn Mountains, Clear Creek, west of Buffalo Mosier Gulch Picnic Area, 28 Jul 2012, by IM Smith, IMS120041.

Type deposition.

Holotype (♀), allotype (♂), and some paratypes (4 ♀; 3 ♂) deposited in the CNC; other paratypes (2 ♀; 2 ♂) deposited in ACUA.

Diagnosis.

Torrenticola mulleni are similar to other members of the Rusetria "Western 2-Plates" group ( T. nortoni , T. walteri , and T. welbourni ) in having anterio-lateral platelets fused to the dorsal plate, having faint dorsal coloration, and being distributed in the west. Female T. mulleni can be differentiated from other female Western 2-Plates by having a longer medial suture (20-22.5 in T. mulleni , 10-12.5 in others). Male T. mulleni can be differentiated from other male Western 2-Plates by having a longer genital field (130-140 in T. mulleni , 112-125 in others). Additionally, T. mulleni can be differentiated from other Western 2-Plates by being distributed in the Rocky Mountains (Idaho, Montana, Utah and Wyoming) instead of California, Oregon and British Columbia.

Description.

Female (Figure 156) (n = 5) (holotype measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (595-645 (640) long; 415-470 (440) wide) ovoid with faint purple coloration separated into anterior and posterior portions. Anterio-medial platelets (127.5-145 (145) long; 40-47.5 (45) wide). Anterio-lateral platelets (151.25-165 (160) long; 50-57.5 (57.5) wide) fused to dorsal plate. Dgl-4 much closer to the edge of the dorsum than to the muscle scars (distance between Dgl-4 300-330 (320)). Dorsal plate proportions: dorsum length/width 1.37-1.45 (1.45); dorsal width/distance between Dgl-4 1.34-1.47 (1.38); anterio-medial platelet length/width 2.95-3.24 (3.22); anterio-lateral platelet length/width 2.75-3.15 (2.78); anterio-lateral/anterio-medial length 1.10-1.29 (1.10).

Gnathosoma - Subcapitulum (300-327.5 (322.5) long (ventral); 225-245 (245) long (dorsal); 125-150 (145) tall) colorless. Rostrum (120-135 (125) long; 40-45 (45) wide). Chelicerae (300-335 (320) long) with curved fangs (40-65 (65) long). Subcapitular proportions: ventral length/height 2.14-2.40 (2.22); rostrum length/width 2.78-3.18 (2.78). Pedipalps with tuberculate ventral extensions on femora and genua. Palpomeres: trochanter (42.5-52.5 (42.5) long); femur (112.5-125 (117.5) long); genu (65-72.5 (67.5) long); tibia (82.5-90 (82.5) long; 26.25-28.75 (26.25) wide); tarsus (17.5-20 (17.5) long). Palpomere proportions: femur/genu 1.70-1.75 (1.74); tibia/femur 0.70-0.78 (0.70); tibia length/width 3.0-3.33 (3.14).

Venter - (720-790 (770) long; 460-500 (490) wide) colorless. Gnathosomal bay (160-175 (175) long; 75-90 (85) wide). Cxgl-4 subapical. Medial suture (20-22.5 (20) long). Genital plates (195-205 (205) long; 170-180 (175) wide). Additional measurements: Cx-1 (285-300 (300) long (total); 115-135 (130) long (medial)); Cx-3 (302.5-335 (320) wide); anterior venter (145-162.5 (155) long). Ventral proportions: gnathosomal bay length/width 1.89-2.16 (2.06); anterior venter/genital field length 0.74-0.80 (0.76); anterior venter length/genital field width 0.85-0.91 (0.89); anterior venter/medial suture 6.89-8.0 (7.75).

Male (Figure 157) (n = 4) (allotypic measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (505-535 (530) long; 350-370 (360) wide) ovoid with faint purple coloration separated into anterior and posterior portions. Anterio-medial platelets (107.5-115 (110) long; 40-41.25 (40) wide). Anterio-lateral platelets (142.5-147.5 (142.5) long; 50-52.5 (52.5) wide) fused to dorsal plate. Dgl-4 much closer to the edge of the dorsum than to the muscle scars (distance between Dgl-4 270-280 (280)). Dorsal plate proportions: dorsum length/width 1.44-1.47 (1.47); dorsal width/distance between Dgl-4 1.29-1.37 (1.29); anterio-medial platelet length/width 2.61-2.88 (2.75); anterio-lateral platelet length/width 2.71-2.95 (2.71); anterio-lateral/anterio-medial length 1.28-1.33 (1.30).

Gnathosoma - Subcapitulum (262.5-277.5 (265) long (ventral); 195-210 (202.5) long (dorsal); 105-110 (105) tall) colorless. Rostrum (100-110 (110) long; 37.5-40 (40) wide). Chelicerae (265-270 (270) long) with curved fangs (50-55 (55) long). Subcapitular proportions: ventral length/height 2.39-2.58 (2.52); rostrum length/width 2.63-2.75 (2.75). Pedipalps with tuberculate ventral extensions on femora and genua. Palpomeres: trochanter (40-40 (40) long); femur (97.5-102.5 (102.5) long); genu (60-65 (62.5) long); tibia (75-82.5 (82.5) long; 26.25-27.5 (27.5) wide); tarsus (17.5-17.5 (17.5) long). Palpomere proportions: femur/genu 1.58-1.64 (1.64); tibia/femur 0.75-0.80 (0.80); tibia length/width 2.73-3.00 (3.00).

Venter - (620-650 (650) long; 390-425 (410) wide) colorless. Gnathosomal bay (130-135 (132.5) long; 70-75 (75) wide). Cxgl-4 subapical. Medial suture (100-105 (102.5) long). Genital plates (130-140 (140) long; 100-110 (110) wide). Additional measurements: Cx-1 (265-285 (285) long (total); 140-145 (140) long (medial)); Cx-3 (290-310 (310) wide); anterior venter (250-260 (250) long). Ventral proportions: gnathosomal bay length/width 1.77-1.93 (1.77); anterior venter/genital field length 1.79-2.00 (1.79); anterior venter length/genital field width 2.27-2.60 (2.27); anterior venter/medial suture 2.38-2.60 (2.44).

Immatures unknown.

Etymology.

Specific epithet ( mulleni ) named in honor of Gary Mullen of Auburn University, who boldly devoted the entire second half of his Arachnology course to mites, and thus, in 2001, first introduced JRF to these creatures, sparking a life-long fascination.

Distribution.

Rocky Mountain region (Figure 155).

Remarks.

Torrenticola mulleni groups with other members of the Rusetria Complex with high support and specimens are less than 2% different in COI sequence from each other. In the all analyses, T. mulleni groups with the three other members of the Rusetria Complex that are found in western North America: T. nortoni , T. walteri , and T. welbourni . These species are 5-7% different in COI sequence from each other. T. mulleni is the only member of the Rusetria Complex that occurs throughout Rocky Mountains. Only T. walteri may overlap with this species in the northern Rockies of British Columbia; however, this overlap is speculative as T. mulleni was not found in any of our British Columbia samples. Young (1969) reported T. indistincta from Colorado, but we suspect this record represents T. mulleni .

Based upon overall similarity, the fusion of the posterio-lateral platelets to the dorsal shield, phylogenetic position, and distribution, we place this species within the Western 2-Plate Identification Group.

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