Testudacarus radwellae O'Neill & Dowling

O'Neill, Joseph C., Fisher, J. Ray, Nelson, Whitney A., Skvarla, Micheal J., Fisher, Danielle M. & Dowling, Ashley P. G., 2016, Systematics of testudacarine torrent mites (Acari, Hydrachnidia, Torrenticolidae) with descriptions of 13 new species from North America, ZooKeys 582, pp. 13-110 : 40-43

Taxon classification Animalia Trombidiformes Torrenticolidae

Testudacarus radwellae O'Neill & Dowling sp. n.

Type series.

Holotype (1♀): Arkansas, USA: 1♀ from Montgomery County, Ouachita National Forest, Collier Springs, at spring structure picnic area (34°29'7.04"N, 93°35'38.12"W), 11 November 2009, by AJ Radwell, AJR090317C (Specimen 144016); Paratypes (1♀, 7♂): Arkansas, USA: (allotype) 1♂ from Montgomery County, Ouachita National Forest, Collier Springs, at spring structure picnic area (34°29'7.04"N, 93°35'38.12"W), 29 July 2011, by AJ Radwell and B Crump, AJR110301 (Specimen 144011); 4♂ from Montgomery County, Ouachita National Forest, Collier Springs, at spring structure picnic area (34°29'7.04"N, 93°35'38.12"W), 29 July 2011, by AJ Radwell and B Crump, AJR110301; 1♂ from Polk County, Ouachita National Forest, upper small pond on stream running along trail (34°27'36.73"N, 93°59'52.38"W), 21 July 2008, by AJ Radwell, AJR080303A; 1♂ from Montgomery County, Ouachita National Forest, Collier Springs, picnic area beside Forest Road 177 (34°29'3.00"N, 93°35'35.00"W), 19 September 2008, by IM Smith, IMS080061A; 1♀ from Montgomery County, Ouachita National Forest, Collier Springs, at spring structure picnic area (34°29'7.04"N, 93°35'38.12"W), 11 November 2009, by AJ Radwell, AJR090317C.

Type deposition.

Holotype (1♀), allotype (1♂), and three paratypes (3♂) deposited at the CNC; four paratypes (1♀, 3♂) at the ACUA.

Diagnosis.

Testudacarus radwellae and Testudacarus vulgaris are the only testudacarines known to occur in Arkansas. Testudacarus radwellae are conspicuously violet over the entirety of their body, whereas the violet coloration of Testudacarus vulgaris is less vibrant and often absent, particularly on the platelets, legs, and secondary sclerotization of the venter. Males of Testudacarus radwellae also have dorsal-glandularia-4 located far lateral to the muscle scars, unlike others in the complex.

Description.

Female (n=2) with characteristics of the genus with following specifications.

Gnathosoma - Subcapitulum [153-155 ventral length; 117-133 dorsal length; 88-97 tall] ovoid with short rostrum. Chelicerae [148-156 long] unmodified with lightly curved fangs [28-29 long]. Pedipalp [177-187 long] unmodified and violet. Trochanter [27-30 long; 26-29 wide]. Femur [46-51 long; 35-38 wide]. Genu [38-42 long; 27-28 wide]. Tibia [44-49 long; 19-20 wide]. Tarsus [18-19 long; 10-11 wide].

Dorsum (Fig. 21) - [556-568 long; 425-444 wide] round to ovoid, completely violet to red–violet in color. Dorsal plate [463-473 long; 366-367 wide]. Primary sclerotization [389-415 long]. Dorso-glandularia-4 [128-132 apart] just anterior to [0-10] and lateral to [33] muscle scars. Platelets completely red–violet including all three anterior platelets. Anterio-medial platelet [134-142 long; 75-81 wide] rounded trapezoid. Anterio-lateral platelets [150-167 long; 69-78 wide]. Lateral platelets as follows: lateral-1 [47-49 long; 28-29 wide]; lateral-2 [113-114 long; 28-34 wide]; lateral-3 [40-47 long; 25-26 wide]; lateral-4 [97-99 long; 25-26 wide]; lateral-5 [38-55 long; 20-28 wide]; lateral-6 [80-83 long; 21-22 wide]; lateral-7 [49-56 long; 25-28 wide].

Venter (Fig. 21) - [717-726 long; 460-476 wide] round to ovoid and completely violet. Primary sclerotization [580-589 long]. Gnathosomal bay [64-72 dorsal length; 148-154 ventral length; 54-59 wide]. Coxal field [442-451 long; 303-309 wide]. Coxa-I [246-250 long; 92-102 midlength]. Coxa-II + III [118-125 distance to top of coxa-II; 181-183 distance to top of coxa-III; 332-335 distance to bottom of coxa-III; 210-214 total length]. Coxa-IV [300-304 distance to top; 142-147 total length]. Genital field [308-311 distance to top; 470-472 distance to bottom; 161-162 total length; 134-136 width; 154-163 distance from gnathosomal bay; 61-62 distance from coxa-I; 156-158 distance to excretory pore; 244-256 distance to caudad]. Distance to excretory pore [628-629].

Legs - violet. Total leg and podomere lengths as follows: Leg-I [464-466 total; trochanter 57-58; basifemur 81-82; telofemur 65-68; genu 83-84; tibia 88-90; tarsus 86-87]. Leg-II [489-490 total; trochanter 54-55; basifemur 81-83; telofemur 64-66; genu 86-87; tibia 97-101; tarsus 102-105]. Leg-III [559-564 total; trochanter 57-58; basifemur 77-85; telofemur 73-76; genu 102-105; tibia 116-117; tarsus 126-130]. Leg-IV [760-767 total; trochanter 86-87; basifemur 107-108; telofemur 108-109; genu 145-146; tibia 158-159; tarsus 152-159].

Male (n=7) similar to female except for sexually dimorphic characters previously discussed and with following specifications.

Gnathosoma - Subcapitulum [132-143 ventral length; 85-90 dorsal length; 81-86 tall]. Chelicerae [107-115 long]. Fangs [25-28 long]. Pedipalp [170-181 long]. Trochanter [25-27 long; 28-30 wide]. Femur [45-52 long; 33-35 wide]. Genu [38-39 long; width 27-29 wide]. Tibia [45-50 long; 18-21 wide]. Tarsus [14-17 long; 8-11 wide].

Dorsum (Fig. 22) - [454-478 long; 330-372 wide]. Dorsal plate [376-405 long; 296-321 wide] without secondary sclerotization. Dorso-glandularia-4 [99-127 apart] far anterior to [74-83] and slightly lateral to [11-27] muscle scars. Anterio-medial platelet [119-138 long; 71-74 wide]. Anterio-lateral platelet [145-163 long; 64-72 wide]. Lateral platelets as follows: lateral-1 [36-45 long; 27-31 wide]; lateral-2 [89-99 long; 24-30 wide]; lateral-3 [39-44 long; 16-25 wide]; lateral-4 [64-77 long; 17-27 wide]; lateral-5 [38-49 long; 17-24 wide]; lateral-6 [48-56 long; 19-22 wide]; lateral-7 [38-45 long; 19-22 wide].

Venter (Fig. 22) - [575-606 long; 369-400 wide]. Primary sclerotization [536-555 long]. Gnathosomal bay [49-66 dorsal length; 130-137 ventral length; 48-56 wide]. Coxal field [405-424 long; 281-305 wide]. Coxa-I [223-238 long; 90-102 midlength]. Coxa-II + III [100-113 distance to top of coxa-II; 156-169 distance to top of coxa-III; 326-346 distance to bottom of coxa-III; 223-244 total length]. Coxa-IV [270-283 length to top; 126-146 total length]. Genital field [343-366 distance to top; 485-510 distance to bottom; 139-146 total length; 115-123 width; 210-232 distance from gnathosomal bay; 90-102 distance from coxa-I; 44-54 distance to excretory pore; 87-101 distance to caudad]. Genital skeleton [179-182 long; 94-103 wide]. Distance to excretory pore [536-555].

Legs - total leg and podomere lengths as follows: Leg-I [440-454 total; trochanter 53-58; basifemur 76-80; telofemur 58-67; genu 75-80; tibia 84-89; tarsus 82-90]. Leg-II [464-478 total; trochanter 52-57; basifemur 75-80; telofemur 58-62; genu 78-86; tibia 94-97; tarsus 99-103]. Leg-III [512-535 total; trochanter 49-55; basifemur 74-83; telofemur 62-69; genu 93-96; tibia 106-116; tarsus 110-125]. Leg-IV [699-726 total; trochanter 77-87; basifemur 101-110; telofemur 99-108; genu 130-133; tibia 144-148; tarsus 133-147].

Etymology.

Specific epithet radwellae after the late Dr Andrea J. Radwell, the American water mite researcher who collected the specimens needed for this description. Dr Radwell collaborated with us on the larger torrenticolid project as a whole, giving us invaluable advice and mentorship. Without her, large portions of this project would not have been possible. She is dearly missed.

Distribution.

Reported from only two counties (Polk and Montgomery) in Arkansas.