Torrenticola rala Cook, 1980

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 rala Cook, 1980

Torrenticola rala Cook, 1980: 394.

Material examined

(11 ♀; 15 ♂). Arizona, USA: 3 ♂ from Coconino County, Oak Creek Canyon, Oak Creek, beside Route 89A, between Banjo Bill & Bootlegger campgrounds, 21 Jul 1987, by IM Smith, IMS870100A • 1 ♂ and 1 ♂ from Cochise County, Chiricahua Mountains, Cave Creek Recreation Area, Cave Creek at John Hand Picnic Area, 15 Jul 1987, by IM Smith, IMS870092B • 1 ♀ from Cochise County, Chiricahua Mountains, Cave Creek Recreation Area, Cave Creek at Stewart campground, 16 Jul 1987, by IM Smith, IMS870094 • 1 ♀ from Cochise County, Chiricahua Mountains, Cave Creek, Herb Martyr Campground, Forest Road 42A 10 May 2012, by IM Smith, IMS120009 • 3 ♀ and 1 ♂ from Gila County, East Verde River, beside Route 87, north of Payson, 19 Jul 1987, by IM Smith, IMS870097 • 2 ♂ from Yavapai County, West Clear Creek at Clear Creek campground, off Forest Road 9, east of Camp Verde, 19-22 Jul 1987, by IM Smith, IMS870098 • New Mexico, USA: • 1 ♂ from Catron County, Glenwood Whitewater Creek at Whitewater Creek Picnic Area, 12 Jul 1987, by IM Smith, IMS870084 • 2 ♀ and 4 ♂ from Catron County, Little Creek, beside Route 15, 65 kilometers north of Route 180 in Silver City, 10 Jul 1987, by IM Smith, IMS870081A • Texas, USA: 1 ♀ and 1 ♂ from Bandera County, Lost Maples State Natural Area, Sabinal River (29°49'N, 99°34'W), 27 Sep 1995, by IM Smith, IMS950052 • 1 ♀ from Bandera County, Vanderpool, beside Route 187, Sabinal River (29°48'10"N, 99°34'30"W), 2 May 2009, by IM Smith, IMS090007 • 1 ♀ and 1 ♂ from Val Verde County, Bakers Crossing Campground, off Route 163, Devils River (29°58'N, 101°9'W), 5 Oct 1999, by IM Smith, IMS990061A • 1 ♀ from Uvalde County, Garner State Park, Frio River (29°35'22"N, 99°44'12"W), 28 May 1998, by IM Smith, IMS980027A.

Type deposition.

Holotype (♂) deposited in prep. no. DC 12-72 FMC. Allotype (♀) deposited in prep. no. DC 43-72 FMC.

Diagnosis.

Torrenticola rala are similar to other members of the Rala Group ( T. boettgeri , T. keesdavidsi , T. kurtvietsi , T. lamellipalpis , T. dolichodactyla , and T. anoplopalpa ) by being colorless, having incomplete hind coxal margins and being distributed in the southwest. T. rala can be differentiated from all other Rala Group by having a stockier rostrum (length/width = 1.63-1.83 in T. rala , 2.19-3.57 in others). Additionally, T. rala can be differentiated from all other Rala Group by having a shorter anterior venter (♀ = 170-185 in T. rala 192-260 in others ♂ = 200-225 in T. rala , 235-308 in others), except male T. keesdavidsi (♂ 225-260).

Re-description.

Female (Figure 209) (n = 5) (holotype measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (630-700 long; 465-505 wide) ellipsoid and colorless. Anterio-medial platelets (150-162.5 long; 62.5-72.5 wide). Anterio-lateral platelets (172.5-195 long; 70-80 wide) free from dorsal plate. Dgl-4 much closer to the edge of the dorsum than to the muscle scars (distance between Dgl-4 370-420). Dorsal plate proportions: dorsum length/width 1.30-1.46; dorsal width/distance between Dgl-4 1.17-1.26; anterio-medial platelet length/width 2.14-2.41; anterio-lateral platelet length/width 2.38-2.79; anterio-lateral/anterio-medial length 1.15-1.26.

Gnathosoma - Subcapitulum (247.5-260 long (ventral); 160-170 long (dorsal); 115-120 tall) tall and colorless. Rostrum (79-89 long; 45-50 wide) short and conical. Chelicerae (217.5-247.5 long) with curved fangs (52.5-60 long). Subcapitular proportions: ventral length/height 2.06-2.17; rostrum length/width 1.70-1.83. Pedipalps short and stocky (especially tibiae) with tuberculate ventral extensions on femora and ventral extensions on genua absent. Palpomeres: trochanter (35-37.5 long); femur (70-77.5 long); genu (50-57.5 long); tibia (55-62.5 long; 20-22.5 wide); tarsus (15-17.5 long). Palpomere proportions: femur/genu 1.35-1.43; tibia/femur 0.79-0.81; tibia length/width 2.75-2.88.

Venter - (760-840 long; 527-585 wide) colorless. Gnathosomal bay (150-162.5 long; 55-62.5 wide). Cxgl-4 apical. Medial suture (25-35 long). Genital plates (175-190 long; 155-170 wide). Additional measurements: Cx-1 (280-300 long (total); 130-145 long (medial)); Cx-3 (345-380 wide); anterior venter (170-185 long). Ventral proportions: gnathosomal bay length/width 2.58-2.73; anterior venter/genital field length 0.92-1.01; anterior venter length/genital field width 1.00-1.19; anterior venter/medial suture 5.00-6.80.

Male (Figure 210) (n = 5) (allotypic measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (600-655 long; 435-480 wide) ellipsoid and colorless. Anterio-medial platelets (135-165 long; 55-67.5 wide). Anterio-lateral platelets (177.5-190 long; 64-82.5 wide) free from dorsal plate. Dgl-4 much closer to the edge of the dorsum than to the muscle scars (distance between Dgl-4 375-400). Dorsal plate proportions: dorsum length/width 1.35-1.42; dorsal width/distance between Dgl-4 1.16-1.20; anterio-medial platelet length/width 2.40-2.48; anterio-lateral platelet length/width 2.30-2.78; anterio-lateral/anterio-medial length 1.15-1.31.

Gnathosoma - Subcapitulum (230-249 long (ventral); 152.5-162.5 long (dorsal); 107.5-112.5 tall) tall and colorless. Rostrum (77.5-81 long; 45-47.5 wide) short and conical. Chelicerae (215-232.5 long) with curved fangs (42.5-50 long). Subcapitular proportions: ventral length/height 2.14-2.21; rostrum length/width 1.63-1.72. Pedipalps short and stocky (especially tibiae) with tuberculate ventral extensions on femora and ventral extensions on genua absent. Palpomeres: trochanter (32.5-37.5 long); femur (65-72.5 long); genu (49-52.5 long); tibia (55-62.5 long; 20-21 wide); tarsus (15-17.5 long). Palpomere proportions: femur/genu 1.33-1.45; tibia/femur 0.79-0.89; tibia length/width 2.71-2.94.

Venter - (710-765 long; 500-540 wide) colorless. Gnathosomal bay (135-145 long; 55-62.5 wide). Cxgl-4 apical. Medial suture (65-80 long). Genital plates (160-185 long; 127.5-135 wide). Additional measurements: Cx-1 (270-295 long (total); 125-145 long (medial)); Cx-3 (337.5-375 wide); anterior venter (200-225 long). Ventral proportions: gnathosomal bay length/width 2.20-2.45; anterior venter/genital field length 1.14-1.33; anterior venter length/genital field width 1.57-1.67; anterior venter/medial suture 2.66-3.31.

Immatures unknown.

Etymology.

Cook (1980) did not specify an etymology for this specific epithet ( rala ) and we are unable to offer helpful speculation.

Distribution.

Southwestern U.S. (Arizona, New Mexico, Texas) and southward through Central America (Figure 208).

Remarks.

Our analyses were unable to confidently place Torrenticola rala phylogenetically. The COI analyses recovers this species at the base of the Raptor Complex, but this relationship was not recovered in the combined analysis. Because of this ambiguity, we refrain from placing this species in a species complex. However, based upon the morphological similarity that this species shares with six other species, we place this species within the Rala Identification Group.

T. rala is greater than 13% different in COI sequence from sister species. This species hypothesis is supported by high divergence between species (3-15%) and by the morphological characters outlined in the diagnosis.