Torrenticola elusiva 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 elusiva Fisher & Dowling sp. n.

Material examined.

HOLOTYPE (♀): from Canada, New Brunswick, Charlotte County, Rollingham, Whittier Ridge, Highway 770, 6.6 km east of covered bridge, 3 Oct 2011, by IM Smith, IMS110120, DNA 1857.

Type deposition.

Holotype (♀) deposited in the CNC.

Diagnosis.

Torrenticola elusiva are similar to other members of the Raptor Group ( T. gnoma , T. irapalpa , T. longitibia , T. mjolniri , T. racupalpa , T. raptor , T. danielleae , T. daemon , and T. ivyae ) in having round bodies; Dgl-4 close to muscles scars; long, thin subcapitular rostra; and long, thin pedipalp tibiae. T. elusiva can be differentiated from T. racupalpa by having a stockier subcapitulum (ventral length/height = 2.39 in T. elusiva , 2.48-2.73 in T. racupalpa ); and by dorsal pattern. T. elusiva can be differentiated from T. irapalpa and T. daemon by having Dgl-4 closer to the muscle scars (dorsal width/distance between Dgl-4 = 2.5 in T. elusiva , 1.59-2.09 in others); a more elongate rostrum (length/width = 3.65 in T. elusiva , 2.66-3.39 in others); and by dorsal coloration and pattern. T. elusiva can be differentiated from T. gnoma by being larger (dorsum length = 645 in T. elusiva , 540-595 in T. gnoma ); having a more elongate rostrum (length/width = 3.65 in T. elusiva , 2.74-3.13 in T. gnoma ); and dorsal coloration. T. elusiva can be differentiated from T. mjolniri and T. ivyae by having stockier pedipalp tibiae (length/width = 4.42 in T. elusiva , 5.00-6.00 in others); and a stockier rostrum (length/width = 3.65 in T. elusiva , 3.81-4.32 in others). T. elusiva can be differentiated from T. raptor by having Dgl-4 closer to the muscle scars (dorsal width/distance between Dgl-4 = 2.50 in T. elusiva , 1.8-2.02 in T. raptor ); shorter anterior venter (163.75 in T. elusiva , 205-240 in T. raptor ); and stockier pedipalp tibiae (length/width = 4.42 in T. elusiva , 6-7.54 in T. raptor ). T. elusiva can be differentiated from T. danielleae by having Dgl-4 closer to the muscle scars (dorsal width/distance between Dgl-4 = 2.5 in T. elusiva , 1.57-1.70 in T. danielleae ) and by dorsal coloration. T. elusiva cannot be confidently differentiated from T. longitibia because T. elusiva is only known from a single female and T. longitibia is only known from two males; however, T. elusiva is only known from Charlotte County, New Brunswick, whereas T. longitibia is only known from Monroe County, Tennessee. Additionally, two character systems that vary minimally between sexes are rostrum and pedipalp tibiae proportions, which do differ between T. elusiva and T. longitibia as follows: pedipalp tibia stockier (4.42 in T. elusiva , 5.5-5.5 in T. longitibia ) and rostrum stockier (3.65 in T. elusiva , 4.15-4.23 in T. longitibia ).

Description.

Female (Figure 71) (n = 1) (holotype only) with characters of the genus with following specifications.

Dorsum - (645 long; 500 wide) circular with bluish-purple coloration posteriorly with a broad anterior extension reaching the anterior edge of the dorsal plate. Anterio-medial platelets (152.5 long; 70 wide). Anterio-lateral platelets (182.5 long; 87.5 wide) free from dorsal plate. Dgl-4 much closer to the muscle scars than to edge of dorsum (distance between Dgl-4 200). Dorsal plate proportions: dorsum length/width 1.29; dorsal width/distance between Dgl-4 2.50; anterio-medial platelet length/width 2.18; anterio-lateral platelet length/width 2.09; anterio-lateral/anterio-medial length 1.20.

Gnathosoma - Subcapitulum (340 long (ventral); 259 long (dorsal); 142.5 tall) colorless. Rostrum (155 long; 42.5 wide) elongate. Chelicerae (333 long) with curved fangs (59 long). Subcapitular proportions: ventral length/height 2.39; rostrum length/width 3.65. Pedipalps elongate (especially tibiae) with tuberculate ventral extensions with dentate tip on femora and tuberculate ventral extensions on genua. Palpomeres: trochanter (48.75 long); femur (132.5 long); genu (72.5 long); tibia (105 long; 23.75 wide); tarsus (17.5 long). Palpomere proportions: femur/genu 1.83; tibia/femur 0.79; tibia length/width 4.42.

Venter - (730 long; 554 wide) colorless. Gnathosomal bay (176.25 long; 87.5 wide). Cxgl-4 subapical. Medial suture (17.5 long). Genital plates (167.5 long; 150 wide). Additional measurements: Cx-1 (288 long (total); 115 long (medial)); Cx-3 (384 wide); anterior venter (163.75 long). Ventral proportions: gnathosomal bay length/width 2.01; anterior venter/genital field length 0.98; anterior venter length/genital field width 1.09; anterior venter/medial suture 9.36.

Male unknown.

Immatures unknown.

Etymology.

Specific epithet ( elusiva ) refers to the fact that we were only able to find a single specimen of this species, despite extensive searching among the abundant samples taken from the type locality in New Brunswick.

Distribution.

Known only from Charlotte County, New Brunswick (Figure 70).

Remarks.

Torrenticola elusiva groups with other members of the Raptor Complex in all analyses with high support. Only one specimen could be acquired for use in our analyses, so differences in COI sequence across specimens could not be investigated, but this single specimen was greater than 4% different in COI sequence from sister species. Furthermore, this species is known from only a single female, so morphological variation could not be investigated. However, this specimen was different enough in terms of morphology and sequence to warrant a separate description. We place this species within the Raptor Identification group based upon similarity with those species.

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