Unduloribates dianae, Behan-Pelletier, Valerie M. & Walter, David E., 2009

Behan-Pelletier, Valerie M. & Walter, David E., 2009, Unduloribates from North America (Acari, Oribatida, Unduloribatidae), Zootaxa 2294, pp. 47-61 : 50-56

Unduloribates dianae sp. nov.

Material examined

Holotype: adult female, NOVA SCOTIA: Cape Breton Highlands National Park, Skyline Trail, 30.viii.1984 (V. Behan-Pelletier) from Arctostaphylos , Vaccinium litter at edge of cliff; deposited in the CNC, type number 23904. Paratypes: 25 with same data as holotype; CANADA: BRITISH COLUMBIA: Haynes Lease Ecological Reserve, 19.v.1984 (R.A. Cannings) 1; ALBERTA: 1 male, (57°04’ N, 110°58’ W), 106 km NNE Fort McMurray, 14.vi.2007, (D.E. Walter) litter under Jack Pine with understory of shrubs, moss, and sparse grass; 4 females, 2 males, (57°38’ N, 110°37’ W), 108 km NNE Fort McMurray, 5.vi.2007, (D.E. Walter) litter under Black Spruce with understory of shrubs, moss, and sparse grass; 1 male, (57°38’ N, 110°37’ W), 108 km NNE Fort McMurray, 14.vi.2008, (D.E. Walter); 1 female, (57°47' N, 116°01' W), 118 km SSE La Crete, 27.v.2008, (D.E. Walter); 2 females on slide (one barcoded), 1 female, 2 adults (to SEM), (57°08' N, 113°12' W), 117 km WNW Fort McMurray, 2.vi.2008, (D.E. Walter); 1 female, (57°10' N, 112°53' W), 102 km WNW Fort McMurray, 19.vi.2008, (D.E. Walter); 1 female, 1 male, (55°43 N, 114°55 W), 48 km NNW Slave Lake, 16.vi.2008, (D.E. Walter); 1 male, (55°28' N, 114°44' W), 21 km N Slave Lake, 13.vi.2008, (D.E. Walter); 3 females, (55°28' N, 112°23' W), 71 km NNW Lac la Biche, 29.vi.2007, (D.E. Walter); 1 female, (56°33’ N, 111°19’ W), 13 km SW Fort McMurray Airport, 21.vi.2008, (D.E. Walter) 1 female; Kananaskis field Station, 11.vii.1983 (V. Behan-Pelletier) from trembling aspen litter in aspen and lodgepole pine forest, 4; QUÉBEC, Gaspésie Park, Mont Albert Plateau, 1000m a.s.l., 29.vii.1981 (E.E. Lindquist) from muskeg in tundra, 2; NOVA SCOTIA: Cape Breton Highlands National Park, Paquettes Lake Trail, 29.viii.1984 (V. Behan-Pelletier) from Empetrum nigrum and lichen on top of Glasgow Lake hill, 24; Aspy River, North Branch, 9.ix.1983 (V. Behan-Pelletier) from spruce and maple litter, 2; Mica Mountain barrens, 12.ix.1983 (V. Behan-Pelletier) from Empetrum , moss, lichens and Vaccinium litter, 8; NEWFOUNDLAND, Labrador, road in Forteau area, 13.viii.1976 (E. E. Lindquist) from sphagnum, herbs, low shrubs in tundra-like bog, 2; USA: NEW YORK: Catskill Mountains, Armstrong Summit, 1341m a.s.l., 24.v.1973 (T. Finger) from litter under stunted balsam, 1; Adirondack Mountains, Mt. Algonquin, 1700m a.s.l., 16.viii.1985 (V. Behan- Pelletier) from moss, Vaccinium in alpine zone, 1; same data, from moss between rocks in alpine zone, 1; deposited in the USNM, PMAE.IZ, RNC and CNC.

Other material examined: ALBERTA: scanning electron micrographs of 1 female, 3 unsexed adults, (57°38’ N, 110°37’ W), 108 km NNE Fort McMurray, 14.vi.2008, (D.E. Walter); 1 female, 2 unsexed adults, (57°08’ N, 113°12’ W), 117 km WNW Fort McMurray, 2.vi.2008, (D.E. Walter).

Diagnosis

Total length of adults 614–691 μm; setae in about 38–41 µm long, thick, heavily barbed, isodiametric along length; tutorium narrow knife-like, about 197 µm long, with tutorial cusp about 91 µm long; custodium about 10 µm long; coxisternal setation 3-1-3-2; 6 pairs of smooth genital setae.

Description of Adult

Measurements: Mean total length: female (n = 10) 670 µm (range 653–691); male (n = 6) 637 µm (range 614–653). Mean notogastral width: female (n =7) 421 µm (range 403–442); male (n =5) 401 µm (range 384–413).

Color: Mature adults dark brown.

Cerotegument: Birefringent and blocky on all of notogaster and ventral plate, up to 15 µm in depth ( Figs 4, 5 , 8, 9 ). Lenticular region either covered with single block of cerotegument or without cerotegument ( Figs. 1 , 5 , 9 ).

Integument: All sclerotized integument microtuberculate, with convex polygonal pattern on notogaster about 10 µm at widest dimension ( Figs. 6 , 9 ); posterior margin of notogaster with longitudinal ridges ( Fig. 2 ). Ventral plate with irregular tubercles, forming longitudinal ridges lateral of anal region ( Fig. 2 ). Lamella with irregular longitudinal ridges ( Figs. 1 , 9 ). Transverse ridges on femora of leg segments and palp ( Fig. 15 ).

Prodorsum: Lamellae long, broad, total length about 216–218 µm; lamellar cusps 115–125 µm long, almost touching medially, widest distance between cusps about 7 µm; with tapered medial and lateral dens, about 22 µm long ( Figs. 1 , 9 ). Setae ro 72–82 µm long, barbed along length, tapered, borne on distinct tubercle, mutual distance about 120–125 µm; ridge extending from this tubercle anteriorly along lateral edge of rostrum ( Figs. 3 , 10 ). Setae le about 72–74 µm long, flattened, fusiform, heavily barbed dorsally ( Figs. 1 , 9 ), mutual distance of pair about 41–48 µm. Setae in about 38–41 µm long, thick, heavily barbed, isodiametric along length; mutual distance of pair about 72 µm ( Fig. 1 ). Bothridial setae 72–96 µm long, with heavily barbed clavate to broadly clavate head, subequal in length to narrow stalk ( Fig. 7 ). Bothridium with internal ring-like ridges. Exobothridial setae about 48 µm long, barbed, tapered. Dorsophragmata fused basally ( Fig. 1 , arrow).

Lateral Region: Vertical incision on rostrum framing broad subrectangular region, with edge of rostrum overlapping vertical incision ( Fig. 3 , arrow). Subrectangular region with longitudinal ridge extending posteriorly, merging, or not, with base of pedotectum I ( Fig. 3 ). Tutorium narrow knife-like, about 197 µm long, with tutorial cusp about half length of fused portion of tutorium, about 95 µm long ( Fig. 3 ). Curved ridge extending from tutorium to subrectangular region just posterior to tubercle bearing rostral seta ( Fig. 3 ). Pedotectum I convex throughout, extending from base of bothridium to epimere I and covering base of seta ex; with curved longitudinal ridge along ventral half of length ( Fig. 3 ). Pedotectum II covering part of acetabulum II ( Fig. 3 ). Discidium present between acetabula II and III, merging with circumpedal carina posteriorly and with short, blunt, tuberculate custodium anteriorly. Custodium about 10 µm long, opposing posteromedial edge of pedotectum II ( Fig. 3 ).

Notogaster: Longer than wide, ratio about 1.2:1.0. Lenticulus irregular oblong in shape, about 96 x 48 µm. All notogastral setae heavily barbed, isodiametric along length; c setae 70–84 µm, l series setae 72–84 µm, h series setae 77–91 µm, p series setae 58–65 µm; setae directed as in Fig. 1 . Lyrifissures, other than im, difficult to see because of cerotegument.

Ventral Region: Coxisternal setation 3-1-3-2. Epimeral setae heavily barbed, about 14–19 µm, with seta 1b longest seta. With short ridges in coxisternal region, and concave ridge framing setae 3a ( Fig. 2 ). Six pairs of smooth genital setae, about 19 µm long (single individual with five pairs of setae, illustrated in Fig. 2 ). Aggenital setae smooth about 19 µm long; anal setae smooth to faintly barbed, 12–17 µm long, with an1 longest; adanal setae barbed, tapered, ad1 about 50 µm, ad2 about 30 µm, ad3 about 18 µm.

Gnathosoma: Mentum with distinct concave ridging ( Fig. 13 ). Subcapitular setae a, m smooth, acuminate, h barbed, tapered; lengths about 29, 38, 19 µm, respectively. Palp femur with transverse ridges on abaxial face ( Fig. 15 ). Palpal eupathidium acm attached to solenidion along distal three-quarters of length ( Fig. 15 ). Axillary saccule of subcapitulum 16 x 5 µm.

Legs: Femora I to IV and trochanters III and IV with porose areas on adaxial surface; with rugose integument and transverse ridges on abaxial surface (not illustrated). Leg setal formulae (trochanter to tarsus): leg I, 1-5-3(1)-4(2)-20(2); leg II, 1-5-3(1)-4(1)-15(2); leg III, 2-3-1(1)-3(1)-15; leg IV, 1-2-2-3(1)-12. Setae l” on genua I and II, on tibia II, ft” on tarsus II, l’ on genu IV, on tibia III and IV, and ft’ on tarsus III spinous, almost penicillate; seta l’ on genu III long, barbed, tapered, longer than genual setae on other legs; seta ft” on tarsus IV strongly barbed, tapered ( Figs. 16–19); all these setae strongly birefringent throughout. Other setae on leg segments barbed, tapered, strongly birefringent only proximally.

Descriptions of Immatures

Measurements: Mean length: larva (n = 7) 196 µm (range 278–307); protonymph (n = 4) 390 µm (range 384–408); deutonymph (n = 3) 513 µm (range 500–525); tritonymph (n = 4) 649 µm (range 634–663).

Tritonymph

Integument: Sclerotized with light brown coloration.

Prodorsum: Aspis with transverse porose area posterior to setae in and bothridia. Lateral porose areas present anterior of bothridia, broadest posteriorly, slightly narrowing anteriorly ( Fig. 20 ). Pair of ridges extending from lamellar setae posteriorly to meet with transverse ridge just anterior to bothridia ( Fig. 20 ). Seta ro finely barbed along length, acuminate, about 24 µm long. Seta le thick, heavily barbed, tapered, about 55 µm long. Seta in about 7 µm long, thick, barbed, strobiliform. Seta ex about 14 µm long, thick, heavily barbed, penicillate. Bothridial seta about 72 µm long, barbed, clavate, head subequal in length to stalk, identical in shape to that of adult.

Gastronotic Region: Integument with hexagonal sculpturing; plicae slightly varying in extent of sclerotization, with alternatively slightly sclerotized and more heavily sclerotized regions; with 5–8 ringlike pits positioned lateral of each seta da ( Fig. 20 ). Gastronotal setae of c, d, l, h and p series about 13–16 µm long, thick, heavily barbed, penicillate, subequal in length to seta ex ( Fig. 20 ).

Ventral Region: Medial margins of epimeral plates weakly defined. Epimere I with broad mentotectum, greatest width about 29 µm, overlying base of subcapitulum. Epimeral, genital, aggenital, anal and adanal setae smooth, acuminate, about 12 µm long. Large area of porose integument surrounding opening of opisthonotal gland ( Fig. 20 ). Development of epimeral setae (larva – adult): 3-1-2, 3-1-2-1, 3-1-2-2, 3-1-3-2, 3-1-3-2. Development of genital, aggenital, anal and adanal setae (larva – adult): 0-1-3-5-6, 0-0-1-1-1, 0-0-0- 2-2, 0-0-2-3-3, respectively (single tritonymph with 6 pairs genital setae).

Gnathosoma: Axillary saccule present in all immature instars. Palpal eupathidium acm attached to solenidion along distal three-quarters of length in all immature instars.

Legs: Development of setae and solenidia given in Table 1 . Proral setae of tarsus I appear eupathidial in all nymphal instars. Subunguinal seta of tarsus I of normal form and inserted proximal to antelateral pair in all nymphs; becoming eupathidial in adult, and moving distal to antelateral pair. Porose areas on femora I to IV clearly present from protonymph. Distal setae on tarsi I–IV with ‘shepherd’s crook’ distally. Setae l” on genua I and II, on tibia II, ft” on tarsus II, l’ on genu IV, on tibia III and IV, and ft’ on tarsus III spinous, almost penicillate, as in adult.

Protonymph and Deutonymph

As for tritonymph, except overall size and length of setae proportionally shorter, other than seta in, subequal in length to that of tritonymph. Gastronotal setae of protonymph about 10 µm, with p1 longest setae; that of deutonymph about 12 µm.

Larva

As for tritonymph, except weakly sclerotized, hexagonal sculpturing not evident. Overall size and length of setae proportionally shorter, other than seta in, subequal in length to that of tritonymph; gastronotal setae about 8 µm, barbed, seta h1 weakly barbed, about 14 µm ( Fig. 21 ).

Distribution and Ecology

This species is widely distributed throughout the northern Nearctic from Labrador, Nova Scotia, Québec to Alberta and British Columbia, where it has been recorded from boreal forest litter and from taiga. It has also been recorded from alpine habitats in the Catskill and Adirondack Mountains of New York State.

Figures

FIGURES 4 – 6. Unduloribates dianae sp. nov., scanning electron micrographs of adult females: 4, ventral aspect; 5, dorsal aspect; 6, notogaster with much of cerotegument removed. Scale bars: 100 µm.

FIGURES 7 – 12. Unduloribates dianae sp. nov., scanning electron micrographs; figures 7 - 10, 12 of adult females; 7, detail of bothridium and bothridial seta; 8, detail of blocky cerotegument on notogaster; 9, detail of prodorsum and anterior of notogaster; 10, prodorsum, lateral aspect; 11, egg in female hysterosoma; 12, tarsus I and anterior of tibia I. Scale bars: 7, 8, 11, 12, 10 µm; 9, 10, 20 µm.

FIGURES 1 – 3. Unduloribates dianae sp. nov., adult female: 1, dorsal aspect, dorsophragmata indicated by arrow; 2, ventral aspect (legs removed); 3, prodorsum, lateral aspect (gnathosoma, notogaster and legs removed). Scale bars: 100 µm.

FIGURES 13 – 15. Unduloribates dianae sp. nov., scanning electron micrographs of adult females; 13, gnathosoma, ventral aspect; 14, gnathosoma, anterior aspect; 15, pedipalp with lateral detail of gena and rutellum. Scale bars: 20 µm.

FIGURES 20 – 21. Unduloribates dianae sp. nov., immatures; 20, tritonymph, dorsal aspect, legs removed; 21, larva, dorsal aspect, legs removed. Scale bars: 50 µm.