Torrenticola rockyensis 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 rockyensis Fisher & Dowling sp. n.

Material examined.

HOLOTYPE (♀): from USA, Idaho, Blaine County, Sawtooth National Forest, Salmon River (43°53'7"N, 114°46'15"W), 29 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0729-002, DNA 2623.

PARATYPES (4 ♀; 6 ♂): Idaho, USA: 2 ♀ and 2 ♂ from Blaine County, Salmon River, beside Route 75 between Obsidian & Galena Summit, 3 Jul 1985, by IM Smith, IMS850067 • 1 ♂ from Blaine County, Sawtooth National Forest, Salmon River (43°53'7"N, 114°46'15"W), 29 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0729-002 • 2 ♀ and 3 ♂ from Custer County, Basin Creek campground, beside Route 75 between Sunbeam & Stanley Basin Creek, 2 Jul 1985, by IM Smith, IMS850066 • 1 ♀ and 1 ♂ from Custer County, Challis National Forest, Stanley Creek (44°15'12"N, 115°0'19"W), 30 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0730-005 • 1 ♀ and 1 ♂ from Custer County, Salmon River (44°12'31"N, 114°55'51"W), 29 Jul 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0729-003 • 1 ♂ from Custer County, Stanley, Little Redfish Lake, 3 Jul 1985, by IM Smith, IMS850069 • 2 ♀ from Lemhi County, North Fork of Salmon River, beside Route 93, 15 kilometers north of North Fork, 1 Jul 1985, by IM Smith, IMS850062 • 1 ♂ (ALLOTYPE) from Lemhi County, Salmon National Forest, Niapas Creek (45°8'15"N, 114°13'4"W), 2 Aug 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0802-003, DNA 2626 • 1 ♀ from Lemhi County, Salmon National Forest, Niapas Creek (45°8'15"N, 114°13'4"W), 2 Aug 2012, by JR Fisher, WA Nelson, & JC O’Neill, ROW 12-0802-003 • Montana, USA 1 ♂ from Missoula County, Lolo National Forest, Lolo Creek (46°41'51"N, 114°32'34"W), 7 Aug 2012, by JR Fisher, WA Nelson & JC O’Neill, ROW 12-0807-002 • 1 ♀ from Missoula County, Lolo National Forest, 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 • 1 ♂ from Ravalli County, Bitterroot National Forest, Soda Spring Creek (45°47'12"N, 114°21'2"W), 6 Aug 2012, by JR Fisher, WA Nelson & JC O’Neill, ROW 12-0806-001 • 1 ♀ and 1 ♂ from Ravalli County, Medicine Springs, Spring Gulch campground, East Fork of Bitterroot River, beside Route 93, 1 Jul 1985, by IM Smith, IMS850060.

Type deposition.

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

Diagnosis.

Torrenticola rockyensis are similar to members of the Miniforma group ( T. copipalpa , T. manni , T. miniforma , T. pacificensis , T. oliveri , and T. pinocchio ) in having short, stocky pedipalps (except T. oliveri and T. pinocchio ); similar pedipalpal extensions (unique to members of this group); and being among the smallest Torrenticola in the west (dorsum 500-625 long) (except T. oliveri ). T. rockyensis can be differentiated from all other Miniforma group by being distributed in the Rocky Mountains. T. rockyensis are best differentiated from T. copipalpa by having tuberculate pedipalp femoral extensions (broad and flat in T. copipalpa ). T. rockyensis are best differentiated from T. pacificensis by females having more elongate subcapitular rostra (length/width ♀ = 2.72-2.91 in T. rockyensis , 2.59-2.68 in T. pacificensis ). T. rockyensis are best differentiated from T. manni by having stockier pedipalp tibiae (length/width = 2.47-3.11 in T. rockyensis , 3.13-3.38 in T. manni ). T. rockyensis are best differentiated from T. miniforma by being larger (dorsum length ♀ = 570-620 in T. rockyensis , 545 in T. miniforma ; ♂ = 525-545 in T. rockyensis , 485 in T. miniforma ) and having stockier subcapitular rostra (length/width ♀ = 2.72-2.91 in T. rockyensis , 3.13 in T. miniforma ; ♂ = 2.83-3.00 in T. rockyensis , 3.19 in T. miniforma ). T. rockyensis can be differentiated by having a shorter anterior venter (175-223 in T. rockyensis , 250-310 in T. oliveri ) and less elongate pedipalpal tibiae (length/width = 2.4-3.1 in T. rockyensis , 3.6-4.2 in T. oliveri ). T. rockyensis can be differentiated from T. pinocchio by having a less elongate rostrum (length/width = 2.7-3.0 in T. rockyensis , 4.5-4.9 in T. pinocchio ).

Description.

Female (Figure 226) (n = 5) (holotype measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (570-620 (620) long; 400-420 (400) wide) ovoid with purple coloration often restricted posteriorly, occasionally encroaching anteriorly nearly to the platelets (one specimen with purple on the platelets). Anterio-medial platelets (110-120 (120) long; 43.75-52.5 (52.5) wide). Anterio-lateral platelets (160-172.5 (172.5) long; 52.5-62.5 (62.5) wide) free from dorsal plate. Dgl-4 much closer to the edge of dorsum than to the muscle scars (distance between Dgl-4 290-310 (300)). Dorsal plate proportions: dorsum length/width 1.43-1.55 (1.55); dorsal width/distance between Dgl-4 1.33-1.38 (1.33); anterio-medial platelet length/width 2.19-2.51 (2.29); anterio-lateral platelet length/width 2.76-3.05 (2.76); anterio-lateral/anterio-medial length 1.43-1.55 (1.44).

Gnathosoma - Subcapitulum (300-315 (302.5) long (ventral); 222.5-235 (231) long (dorsal); 115-122.5 (117.5) tall) colorless. Rostrum (117.5-130 (123.75) long; 42.5-45 (42.5) wide). Chelicerae (283-310 (283) long) with curved fangs (52.5-68 (67) long). Subcapitular proportions: ventral length/height 2.49-2.68 (2.57); rostrum length/width 2.72-2.91 (2.91). Pedipalps short and stocky (especially tibiae) with tuberculate (occasionally broadly tuberculate), dentate ventral extensions on femora and dentate, flanged ventral extensions on genua. Palpomeres: trochanter 35-42.5 (42.5) long); femur (90-95 (95) long); genu (63.75-67.5 (67.5) long); tibia (62.5-70 (70) long; 21.25-23.75 (22.5) wide); tarsus (12.5-17.5 (15) long). Palpomere proportions: femur/genu 1.38-1.46 (1.41); tibia/femur 0.68-0.74 (1.74); tibia length/width 2.78-3.11 (3.11).

Venter - (615-770 (760) long; 339-470 (455) wide) colorless. Gnathosomal bay (120-147.5 (145) long; 65-80 (67.5) wide). Cxgl-4 subapical. Medial suture (42.5-60 (52.5) long). Genital plates (172.5-190 (185) long; 157.5-173.75 (170) wide). Additional measurements: Cx-1 (239-279 (279) long (total); 112-133 (121) long (medial)); Cx-3 (247-310 (296) wide); anterior venter (175-202.5 (190) long). Ventral proportions: gnathosomal bay length/width 1.71-2.27 (2.15); anterior venter/genital field length 0.99-1.07 (1.03); anterior venter length/genital field width 1.08-1.19 (1.12); anterior venter/medial suture 3.13-4.29 (3.62).

Male (Figure 227) (n = 5) (allotypic measurements in parentheses when available) with characters of the genus with following specifications.

Dorsum - (525-545 (535) long; 335-350 (350) wide) ovoid with purple coloration often restricted posteriorly, occasionally encroaching anteriorly nearly to the platelets. Anterio-medial platelets (102.5-106.25 (105) long; 45-47.5 (45) wide). Anterio-lateral platelets (145-155 (152.5) long; 52.5-55 (52.5) wide) free from dorsal plate. Dgl-4 much closer to the edge of dorsum than to the muscle scars (distance between Dgl-4 255-285 (280)). Dorsal plate proportions: dorsum length/width 1.53-1.57 (1.53); dorsal width/distance between Dgl-4 1.23-1.31 (1.25); anterio-medial platelet length/width 2.21-2.36 (2.33); anterio-lateral platelet length/width 2.68-2.90 (2.90); anterio-lateral/anterio-medial length 1.36-1.51 (1.45).

Gnathosoma - Subcapitulum (270-285 (285) long (ventral); 197.5-208 (207) long (dorsal); 102.5-107.5 (107.5) tall) colorless. Rostrum (106.25-112.5 (112.5) long; 36.25-38.75 (37.5) wide). Chelicerae (269-284 (282) long) with curved fangs (41-52 (46) long). Subcapitular proportions: ventral length/height 2.62-2.67 (2.65); rostrum length/width 2.83-3.00 (3.00). Pedipalps short and stocky (especially tibiae) with tuberculate (occasionally broadly tuberculate), dentate ventral extensions on femora and dentate, flanged ventral extensions on genua. Palpomeres: trochanter (30-40 (31.25) long); femur (81.25-86.25 (86.25) long); genu (57.5-60 (60) long); tibia (52.5-62.5 (62.5) long; 21.25-22.5 (22.5) wide); tarsus (12.5-15 (15) long). Palpomere proportions: femur/genu 1.41-1.44 (1.44); tibia/femur 0.62-0.74 (0.72); tibia length/width 2.47-2.82 (2.78).

Venter - (580-690 (690) long; 352-420 (385) wide) colorless. Gnathosomal bay (130-140 (140) long; 57.5-62.5 (62.5) wide). Cxgl-4 subapical. Medial suture (75-92.5 (92.5) long). Genital plates (137.5-147.5 (143.75) long; 105-113.75 (110) wide). Additional measurements: Cx-1 (234-266 (266) long (total); 98.25-137 (136) long (medial)); Cx-3 (245-270 (260) wide); anterior venter (197.5-222.5 (215) long). Ventral proportions: gnathosomal bay length/width 2.12-2.26 (2.24); anterior venter/genital field length 1.42-1.51 (1.50); anterior venter length/genital field width 1.82-1.98 (1.95); anterior venter/medial suture 2.32-2.73 (2.32).

Immatures unknown.

Etymology.

Specific epithet ( rockyensis ) refers to the distribution of this species in the Rocky Mountains. This location-based naming reflects that locality is the easiest way to differentiate this species from others in the Miniforma Group, particularly T. pacificensis .

Distribution.

Rocky Mountains of Idaho and Montana (Figure 225).

Remarks.

Torrenticola rockyensis groups with other members of the Miniforma group in all analyses with high support. All specimens are less than 1% different in COI sequence from each other and are greater than 5% different from other members of the group. This species is the only member of the Miniforma group that occurs in the Rocky Mountains.

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

Torrenticola rockyensis groups with other members of the Miniforma Complex with high support and specimens of this species are less than 1% different in COI sequence from each other. In all analyses, T. rockyensis groups with three other morphologically similar species: T. pacificensis , T. manni , and T. copipalpa . Torrenticola rockyensis is greater than 5% different from the other three species in COI sequence and is the only one of the four to occur in the Rocky Mountains.

Based upon overall similarity, the pedipalp genu extensions, and western distribution, we were able to place this species in the Miniforma Identification Group.

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