Paraleius leahae, Knee, Wayne, 2017

Knee, Wayne, 2017, A new Paraleius species (Acari, Oribatida, Scheloribatidae) associated with bark beetles (Curculionidae, Scolytinae) in Canada, ZooKeys 667, pp. 51-65 : 53-56

Paraleius leahae sp. n. Figs 1, 2, 3, 4, 5, 6

Material examined.

Type material. Holotype: adult female (vial CNC649357) on Hylastes porculus (female) collected in Westfield, Nova Scotia, Canada (44.40316, -64.97473), 28.v.2009, coll: W. Knee.

Paratypes (20): one female (vial CNC649359) with the same collection information as the holotype; female (vial CNC649361) on H. porculus (male), St. Stephen, Highway 1, New Brunswick (45.22321, -67.15371), 15.vi.2009, coll: W. Knee; female (vial CNC649362) on H. porculus (male), Bayside, Route 127, New Brunswick (45.20539, -67.14034), 15.vi.2009, coll: W. Knee; male (vial CNC649363) on H. porculus (female), Turner and Turner Mill, West Northfield, Nova Scotia, 1.vi.2009, coll: W. Knee; two females and two males (slides CNC649365-649368) on H. porculus , Algonquin Provincial Park (PP), Ontario (45.902, -77.605), 17.vi.2008, coll: W. Knee; one female and three males (slides CNC649371-649374) on H. porculus , Algonquin PP, Ontario (45.902, -77.605), 3.vi.2008, coll: W. Knee; two females (slides CNC649375, CNC649376) on Dendroctonus valens , Algonquin PP, Ontario (45.895, -78.071), 3.vi.2008, coll: W. Knee; three females and three males (slides CNC649378-649383) on D. valens , Algonquin PP, Ontario (45.895, -78.071), 28.v.2008, coll: W. Knee.

Other material.

67 slide mounted specimens from D. valens , and 22 from H. porculus collected in Algonquin PP, Ontario (45.895, -78.071), 2008-2009, coll: W. Knee; one slide mounted specimen from D. valens , and 70 from H. porculus collected in Algonquin PP, Ontario (45.902, -77.605), 2008-2009, coll: W. Knee.

Diagnosis adult.

As for Paraleius (see above). Bothridial seta long and fusiform, covered with numerous spicules; carina kf present; tarsi monodactylous with prominent sickle shaped strongly hooked claw; solenidia of tibiae III and IV not microcephalic. Immatures unknown.

Description.

Measurements. Total length female (n = 4) 453 (432-464), male (n = 7) 430 (423-440). Total width female (n = 4) 277 (255-296), male (n = 7) 274 (258-295).

Integument. Body cuticle red-brown. Notogastral surface and venter appear smooth, but with fine granulate structure at higher magnification (100x). Small microtubercles on epimeral surface (Fig. 4). Small microtubercles medially on subcapitulum between h setae.

Prodorsum (Figs 1, 3). Lamella narrow, about 63 long. Prolamella narrow, extending from base of seta le to slightly anterior to ro, about 47 long. All prodorsal setae long, thickened, attenuate, barbed, reaching beyond rostrum; ro 78 (63-85) and le 95 (91-102) directed anteriorly, in 127 (121-137) directed anterodorsally. Mutual distance of setal pairs ro, le, and in ~53, 54, and 56 respectively. Bothridial seta long 85 (79-89), fusiform, directed anterolaterally, spicules conspicuous on head and minute along stalk. Seta ex medium sized 55 (52-59) thick, attenuate and barbed.

Lateral aspect of podosoma (Figs 3, 4). Carina kf present. As for other scheloribatids pedotectum I large, visible from dorsal aspect. Pedotectum II smaller and less visible than pedotectum I. Circumpedal carina weakly curved, extending slightly posterior of acetabulum IV. Sublamellar porose area Al present. Humeral porose organ Ah (~14 length, 11 width) expressed as saccule. Gland opening z ventral to ex.

Notogaster (Figs 1, 3). Longer than wide, ratio approximately 1.3:1. Dorsophragma (D) small, oval, approximately 8 wide. Ten pairs of medium sized notogastral setae 29 (19-38), setiform, smooth. Four pairs of saccules present: Sa largest (~9 diameter of saccule), located lateral to seta la; S1 (~7) lateral to lp; S2 (~6) posterolateral to h3; S3 (~6) posterior to h1. Lyrifissure ia posterolateral of seta c2; im posterolateral of lm; ih anterolateral to p3; ips posterolateral to p3; ip lateral to p1. Opisthonotal gland opening (gla) posterior of lyrifissure im.

Venter (Figs 2, 3). Epimeral setal formula 3-1-3-3. All epimeral setae setiform and slightly barbed except for smooth setae 2b, 4a, and 4b. Setal lengths as follows: 1a, 1b, 1c ~26, 30, 25, respectively; 2a, 3a, 3b, 3c ~ 29, 28, 26, 26; and 4a, 4b, 4c ~ 18, 22, 24. Shallow sternal groove present, approximately 69 long. Genital plates nearly as wide as long, genital plates of female slightly larger than those of male; length to width in females 61x58 and in males 55x51. Four pairs of simple setiform genital setae 14-21 long. Single pair of simple setiform aggenital setae (19), three pairs of simple setiform adanal setae ad1, ad2, ad3 ~24, 26, 27, and two pairs of simple setiform anal setae (23). Lyrifissure iad very close to anal plates, about midway between levels of setae ad2 and ad3.

Gnathosoma (Fig. 5). Subcapitulum wider than long; porose region on rutelli. Subcapitular setae setiform, barbed, h (32), m (18), a (18). Adoral setae (or1, or2) thin and barbed. Palp with setation 0-2-1-3-9(1), palpal solenidion ω and seta acm fused (~9), slightly curved near tip. Postpalpal setae (ep) simple, smooth and rounded. Chelicera 108 long, setae attenuate barbed; cha (44), chb (18), Trägårdh’s organ (Tg) elongate triangular, rounded distally.

Legs (Fig. 6; Table 1). All tarsi monodactylous with prominent sickle shaped strongly hooked claw, claw surface smooth except for small bump along inner margin. Large porose areas present on femora I–IV, and on trochanters III and IV. Ventral porose region present distally on tibiae I–IV and proximally on tarsi I–IV; dorsal porose area present distally on tarsi I–IV. Setal formula same as P. leontonycha . Leg setation (solenidia) of leg I: 1 –5–3(1)–4(2)– 19(2); II: 1 –5–2(1)–4(1)– 15(2); III: 2 –3–1(1)–3(1)– 15; IV: 1 –2–2–3(1)– 12 (Table 1). All setae on trochanters and genua I–IV barbed. Seta l’ on tibiae I, II barbed, all other setae on tibiae and tarsi I–IV with large barbs on one side, ventral setae with noticeably longer barbs than dorsal setae. Eupathidia p of tarsus I (~27), setae p of tarsi II–IV and u of tarsi I–IV with slight barbs unilaterally on ventral side. Famulus (8) short and blunt distally. Solenidia ω 1 on tarsus I baculiform, ω 1 and ω 2 on tarsus II ceratiform, all other solenidia piliform. Solenidia of tibiae III and IV not microcephalic. Bases of solenidia ω 1 and ω 2 on tarsus I positioned very close together.

Gender differences. No sexual dimorphism exists in external morphology, except for males being slightly smaller than females, their genital plates being slightly smaller proportionally than in females, and in the typical genitalic differences.

Genetics. There are no other sequences of Paraleius or Metaleius on GenBank; however, GenBank blast searches of the COI sequence (KY402259) of P. leahae sp. n. generally matches that of other poronotic brachypyline oribatid mites. Further analysis was not performed.

Etymology.

This species is named after my wife and tireless supporter Leah Harper.

Remarks.

Paraleius leahae sp. n. is most similar to P. leontonycha ( Travé 1960, Wunderle et al. 1990), which has been collected from under tree bark, in the galleries of bark beetles, and is phoretic on numerous species of bark beetles ( Vitzthum 1926, Wunderle et al. 1990, Knee et al. 2013). Paraleius leahae sp. n. differs from P. leontonycha by having a long fusiform bothridium; monodactylous tarsi; presence of carina kf; solenidia of tibiae III and IV not microcephalic.

Paraleius leahae sp. n. differs from P. (= Metaleius ) strenzkei in having a long fusiform bothridial seta; monodactylous tarsi, medial claw large and strongly hooked; carina kf present; total length (432-464) of P. leahae females greater than P. strenzkei (310-360) ( Travé 1960).

According to Grandjean (1959) microcephalic solenidia are found only in arboricolous or saxicolous species. Paraleius leontonycha , P. leahae sp. n. and P. strenzkei are arboricolous species, the former has microcephalic solenidia and the latter two species lack this feature. The tips of solenidia on tibiae III and IV are delicate and prone to breakage, so it is possible that they are microcephalic in P. leahae ; however, I examined more than 100 specimens without finding microcephalic tips.