Protoribates haughlandae, Walter, David Evans & Latonas, Sarah, 2013

Walter, David Evans & Latonas, Sarah, 2013, A review of the ecology and distribution of Protoribates (Oribatida, Oripodoidea, Haplozetidae) in Alberta, Canada, with the description of a new species, Zootaxa 3620 (3), pp. 483-499 : 486-492

Protoribates haughlandae sp. n.

Figs 1–17 , Map 1

Diagnosis. As for Protoribates (see above) and body length 470–570, colour reddish-brown, cuticle smooth; sensillus short (~58–65 long), sparsely barbed, ending in long, oboval club directed dorsally; sublamella short (~20), poorly defined; tutorial ridge long (~60) without cusp; notogastral setae very fine (~10–12 long); ventral shield with U-shaped submarginal furrow; discidium with subtriangular, knife-like custodium; femur II without distal ventral tooth; palptarsus double-horn on short, broad apophysis; heterotridactylous.

Description of female (N=22). Body length 460–470. Prodorsum ( Figs 1, 3 , 8–9 ). Smooth, rostrum blunt apically; lamella ~85 long, narrow (10–12), weakly striate longitudinally, without cusp; sublamella poorly defined, extending about one-third length of lamella; tutorial ridge (arrow in Fig 9 ) extending to level of le; sublamellar porose area Al (~21 diameter) near base of lamella above tutorial ridge; bo short (~58–65 long), sparsely barbed, ending in long, oboval club directed dorsally; ex minute (8), smooth; other prodorsal setae sparsely barbed, tapering, acuminate: ro (55–63); le (110–125), subparallel, directed anteriorly, inserted at tip of lamella, extending well past anterior of rostrum; in (115–120) passing anterior tip of lamella.

Notogaster ( Figs 1, 3 ). Smooth, dorsal sejugal fissure distinct throughout; dorsophragmata well developed (15–20 long, ~18 wide), tongue-shaped, well separated (~50); pteromorph subtriangular with rounded tip, hinge (arrow in Fig 4 ) desclerotised over most of length, muscle insertions well developed between Aa and hinge; porose areas oval, surrounded by darker, ring-like rims: Aa largest (18–23 long), A1 (~10–15) inserted between lp and opisthonotal gland opening (gla), A2 (~12), A3 (~10); 10 pairs of short (10–12), fine notogastral setae.

Venter ( Figs 2, 5 , 14 ). Ventral setae mostly short (10–25), simple except g1 sparsely barbed; epimeral setae short (10–12 long), simple, 3a usually transverse, but aligned longitudinally in one specimen; epimeral fields with distinct borders and strong sigillar ornamentation; ap1 procurved, apsj (~65–70) ending in mushroom-like head at epimeral border near genital opening; ap3 (~32) extending about half distance to genital opening. Discidium ( Figs 5 , arrow 14) ~53 long x 20 high, custodium broadly tapering to point. Genital plates (65–73 long) with 3 pairs setae anterior, 2 pairs posterior, g1 (20) longest, others (~12–15) simple; genital papillae with broad (~11 long x 17 wide), rounded glans; ag (~12); ad1 – 3 subequal (20–27), ad3 inserted somewhat anterior to anal opening, ad1 posterior to anal opening; iad adanal, parallel to large anal plates bearing 2 pairs of subequal (18–20) anal setae. Ventral shield with shallow, U-shaped submarginal furrow extending to about level of ag; circumpedal carina well developed; preanal organ normally developed.

Mouthparts ( Figs 8–11 ). Subcapitulum diarthric, adoral setae (20–25) curved, tapering, barbed on one side. Rutellum broad, notched, with two teeth ( Fig 10 ). Chelicerae large, robust (120 long x 55 high), movable digit (35–38) with 3 coarse teeth and distal hook; fixed digit with 2 teeth and hook; cheliceral setae coarsely barbed, tapering; Trägårdh organ small. Palpal setation 0-2-1-3-9(1); dorsal and lateral setae of femur, genu, tibia long, barbed; eupathid acm fused to solenidion to form double-horn on short, broad apophysis ( Figs 10–11 ).

Legs ( Figs 6 , 8 , 12–15 ). All tarsi heterotridactylous, median claws with sparse series of dorsal barbs; tarsi I–III short (60–75), laterally compressed, tarsus IV (65) more cylindrical, all with basal ventral porose areas; all tibiae with ventral porose areas, smallest (~15 long) on tibia IV; femora I–IV, trochanter IV with extensive porose areas on dorso-paraxial side, femora II–IV, trochanter IV with blade-like ventral keels. Leg setation (solenidia) of leg I: 1-5-3(1)-4(2)-20(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. Tarsus I ( Figs 8 , 12 ) excluding claws 65-70 long, famulus minute (4–5) blunt ( Fig 6 ); solenidion ω2 (23) baculiform, ω1 (20) piliform; tibia I with strong apophysis bearing whiplike φ1 (130–150) and more or less ceratiform φ2 (65); genu I δ whiplike (~65). Tarsus II ( Figs 8 , 13 ) 60 long with 15 setae and two solenidia: 7 setal pairs (ft, tc, it, p, u, a, pv); seta s; solenidia ω1 (35), ω2 (32) baculiform; tibia II φ (~85), whiplike; genu II δ whiplike (~45); l” of genu II thick, spine-like (~25 long); femur II ventral keel lineate, running entire length of segment, rounded distally ( Fig 13 ).

Description of male (N=15). Similar to the female except generally smaller (470–520 long) and with spermapositor rather than ovipositor.

Description of deutonymph (N=1). Body ( Figs 16–17 ) flattened, subrectangular, length 430, width 190. Prodorsal shield with uniform micropunctate ornamentation (interlamellar porose areas apparently not present) bearing 5 pairs of setae: bo (45 long) erect, terminating in drop-shape, sparsely spiculate club; in (65 long) thick (2), sparsely barbed; le broken off; ro (48) tapering-acuminate, sparsely barbed, extending well beyond tip of rostrum; ex minute (~3), smooth, erect. Gastronotic region smooth, white, with 15 pairs of sparsely barbed setae, each inserted eccentrically on a small porose sclerite; c 3 in humeral position; h1-3 on posterior margin; p1-3 ventral; many setae broken off but c1 (26), c2 (24), c3 (40), da (26), lm (26), lp (26), p2 (26), p3 (19). Coxal fields with microtuberculate ornamentation on posterior (I, II) and/or anterior (II, III, IV) margins; epimeral setation 3-1- 2-2; genital valves with 2 pairs of setae; 1 ag; 3 ad; anal valves atrichous; 2 pairs of genital papillae. Tarsal claws sickle-shaped with dorsal line of sparse barbs; monodactyl, but claw on tarsus III bifurcate on left side ( Fig 17 arrow); all femora with large porose areas on dorso-paraxial side; leg setation cannot be determined.

Type material. Holotype Ƥ (slide) and 38 paratypes: 8 Ƥ, 8 ♂ (slides), 6 adults (SEM), 15 adults (alcohol), 1 deutonymph (slide), ex organic layer in rich fen, with mostly small black spruce, tamarack, dwarf birch, willow, sedges and grasses, near Freeman Lake 10 km W Swan Hills (ABMI 910 SW 54.68661118, -115.556122), 14.vi.2010; holotype in PMAE.IZ, paratypes in PMAE.IZ, CNC, USNM. Additional paratypes: male, ABMI 13 NE (59.8699646, -112.579437) 10 km SW unnamed road, Wood Buffalo National Park, 12.vi.2009, mature mesic upland black spruce forest with Labrador tea, feathermoss; 2 adults, ABMI 63 SW (59.41637802, -111.659508) 6 km W unnamed road, Wood Buffalo National Park, 26.v.2011, rich fen dominated by tall shrubs, dwarf birch, willow with sedges and grasses; Ƥ, ♂, ABMI 484 SE (57.29631805, -119.8769) 30 km SE Miligan Hills Provincial Park, 4.vi.2007, rich fen with shrubs, dwarf birch, willow, sedges, and grasses; 6 adults, ABMI 391 SW (57.26052475, -110.455292) 80 km NNE Fort McMurray, 31.v.2011, poor fen with shrubs, Labrador tea, sphagnum, sedges; 1 adult, ABMI 392 SW (57.1747551, -110.14296) 90 km NE Fort McMurray, 31.v.2011, poor fen with mostly small black spruce, tamarack and Labrador tea, sphagnum, sedges; 4 Ƥ, 2 ♂, ABMI 515 SW (57.12088013, -119.900093) 25 km W Chinchaga Wildland, 16.vi.2007, bog with black spruce, tamarack, Labrador tea, sphagnum, lichen; Ƥ, ABMI 472 NW (56.99316788, -113.571747) 10 km NNE Chipewyan Lake, 28.v.2008, rich fen, with mostly small black spruce, tamarack, dwarf birch, willow, sedges and grasses; Ƥ, 6 ♂, ABMI BOG6 SW (56.50244, -111.3064) 2 km S jct Routes 63 and 881, 28.vi.2007, untreed area with human disturbance; Ƥ, ABMI 569 NE (56.32915115, -112.424896) 20 km S Grand Rapids Wildland, 27.v.2009, rich fen, with mostly small black spruce, tamarack, dwarf birch, willow, sedges and grasses; 3 adults, ABMI 604 NW, SE (56.03934479, -111.209465) 20 km W Rout 881, Wood Buffalo National Park, 12.vi.2011, poor fen with mostly small black spruce and tamarack, Labrador tea, sphagnum, sedges; 2 adults, ABMI 608 SE (55.91720963, - 110.027626) 3 km NE Graham Lake, 11.vi.2011, rich fen with dwarf birch, willow, sedges, grass; 2 adults, ABMI 608 NE (55.91720963, -110.027626) 3 km NE Graham Lake, 11.vi.2011, poor fen, with shrub cover with Labrador tea, sphagnum, sedges; Ƥ, ♂, ABMI BOG1 SW (55.3271, -112.47242) 200 m E Route 63, 12 km SE of McMillian Lake, 13.vi.2008, rich fen dominated by shrubs, dwarf birch, willow, sedges and grasses; Ƥ, ABMI BOG2 SW (55.30589, -112.48525) 200 m E Route 63, 15 km SE of McMillian Lake, 13.vi.2008, rich fen dominated by shrubs, dwarf birch, willow, sedges and grasses; ♂, ABMI UPL5 SE (55.15843, -113.0178) 1 km E Range Road 203A, SE Calling Lake Provincial Park, 17.vi.2007, bog with Labrador tea, sphagnum, sedges, grasses, and herbs; 2 adults, ABMI A761-4 SE (55.15634537, -111.656158) 5 km NE Buffalo Lake, 8.vi.2011, bog with mostly small black spruce and tamarack, Labrador tea, sphagnum, lichen; ♂, ABMI 881 SW (54.70869064, -114.23317) W Hwy 44 18 km N Hybert Lake Wildland, 26.v.2009, poor fen, with shrub cover, Labrador tea, sphagnum, sedges; ♂, ABMI 883 SE (54.6693573, -113.595978) 6 km E Bleak Lake along RR 244, 2.vi.2009, rich fen with mostly small black spruce, tamarack, dwarf birch, willow, sedges and grasses; Ƥ, ABMI 916 SW (54.49138641, -113.665222) near Bolloque Lake, 31.v.2009, mature moist upland balsam poplar mixed woodland with horsetail, dogwood, rose, willow; ♂, ABMI 974 NW (54.32911682, -116.306122) N Hwy 43 35 km E Fox Creek, 30.v.2008, bog with mature black spruce and tamarack, Labrador tea, sphagnum, lichen; 3 adults, ABMI 1071 SW (53.88096619, - 117.342422) along Willow Creek Road, Yellowhead County, 27.v.2011, mature rich upland balsam poplar mixed forest with dogwood, ferns, feathermoss; ♂, 1170 NE (53.34415054, -117.076775) NE Hwy 47, Yellowhead County, 11.vi.2010, rich fen with mostly small black spruce, tamarack, dwarf birch, willow, sedges and grasses; ♂, 1171 SW (53.28146744, -116.769356) SW Hwy 47, Yellowhead County, 12.vi.2010, mature mesic upland pine forest, with Labrador tea and feathermoss; Ƥ, OG-1210-2 SW (52.93924713, -114.774429) S of Buck Lake, 11.vi.2010, treeless, human disturbed site with grasses, sedges; 3 adults, 1238 SE (52.8145256, -115.467941) 25 km NE Aurora Natural Area, 13.vi.2011, mature mesic upland forest with Labrador tea and feathermoss; 1 adult, OG-1160-1 SW (52.78925323, -110.302109) SE of Porter Lake, 31.v.2011, treeless, human disturbed site with lichens and bryophytes; 4 adults, 1379 SW (51.84659195, -114.763763) along Twp Road 334 N of Sundre, 31.v.2008, rich fen with mostly small black spruce, tamarack, dwarf birch, willow, with sedges and grasses; female, 1379 SE (51.84659195, -114.763763) along Twp Road 334 N of Sundre, 31.v.2008, rich fen with mostly small black spruce, tamarack, dwarf birch, willow, with sedges and grasses; 2 adults, 1439 SW (51.02621841, - 111.178215) S jct Rts 561 and 884, 10.vi.2011, treeless, human disturbed site with grasses, sedges, herbs, ferns; 6 adults, 1439 NE, SE, SW (51.02621841, -111.178215) S of Cabin Lake, 10.vi.2011, treeless, human disturbed site with grasses, sedges, herbs, ferns. In PMAE.IZ.

Ecology and distribution. Protoribates haughlandae sp. n. is found primarily in open peatland habitats including rich and poor fens (alkaline to neutral wetlands fed by ground water) and bogs (acidic wetlands formed from rainwater) and extends into some of the more mesic forests ( Table 1 ). Males were commonly collected and all populations appear to be bisexual. The gravid female can carry up to 6 eggs. Gut boluses were composed primarily of pigmented and unpigmented fungal hyphae and spores, often mixed with small particles of unknown organic matter. Two females had gut boluses with limbs and setae of soft-bodied arthropods indicating opportunistic predation ( Fig 7 ). One female also contained numerous fragments of possible moss spores. The single deutonymph (tentatively assigned to the new species based on its size, sensillus, shape of genital papillae ( Fig 17 ) and the absence of any other Oripodoidea in the sample), has a few fungal spores in the anal region of the gut.

Remarks. The most distinctive character of the new species is the relatively short and erect sensillus ( Figs 3 , 8–9 ), otherwise not reported in the genus, and the heterotridactylous tarsal claws. In these characters the new species resembles some Haplozetes , but possesses the notogastral porose areas typical of other species of Protoribates , rather than saccules (see Weigmann 2010).

Because the new species tends to die with its legs retracted into a defensive position, the discidium is difficult to observe but unlike many Protoribates , that of the new species is not drawn out into a long, needle-like tip as is commonly seen in the genus (e.g. Fig 24 ), but is short and more knife-like, than needle-like. The apophysis bearing the palptarsal double-horn in species of Protoribates is often well developed, forming a strongly hook-like process (see Fig 20 ), but is short and broad in the new species ( Figs 10–11 ), similar to that of P. dentatus (Weigmann et al. 1993, Fig VI 5).

The legs of Protoribates species have been illustrated by Weigmann et al. (1993), Miko et al. (1994), and Ermilov and Anichkin (2011), and the latter have presented a hypothesis of setal homologies. The leg setation of the new species appears to be the same as P. heterodactylus Ermilov and Anichkin (2011) from Vietnam, including the 15 setae on tarsus II (v’ and l’’ apparently absent). Both P. dentatus (Weigmann et al. 1993) and P. lophotrichus (Miko et al. 1994) have 17 setae on tarsus II. Similar interspecific variation in the setation of tarsus II is known in Haplozetes (Beck, 1964) .

Etymology. The new species is named in honour of Dr. Diane Haughland, an ecologist and lichenologist, who during her PhD studies first brought this mite to our attention.

Figures

FIGURES 1 – 7. Protoribates haughlandae sp. n., Alberta, Canada. Adult. 1 dorsal habitus with left pteromorph extended (scale bar = 100 µm) 2 ventral habitus (scale bar = 50 µm) 3 lateral habitus (scale bar = 200 µm) 4 light micrograph of right pteromorph (scale bar = 100 µm, arrow points to hinge) 5 discidium (scale bar = 5 µm) 6 famulus of leg I (scale bar = 1 µm) 7 arthropod cuticle in gut bolus (scale bar = 25 µm).

FIGURES 8 – 11. Protoribates haughlandae sp. n., Alberta, Canada. Adult. 8 lateral view of anterior with legs I – II withdrawn (scale bar = 50 µm) 9 dorso-lateral view of anterior with legs I – II extended to show tutorium (arrow) (scale bar = 30) 10 lateral view mouthparts (scale bar = 10 µm) 11 details of palpal tarsus (it’ not visible, scale bar = 1 µm).

FIGURES 12 – 15. Protoribates haughlandae sp. n., Alberta, Canada. Adult legs in lateral views (scale bars = 10 µm). 12 tarsus and tibia I 13 leg II 14 leg III (arrow points to tip of discidium) 15 leg IV.

FIGURES 16 – 17. Protoribates haughlandae sp. n., Alberta, Canada. Deutonymph (scale bar = 50 µm). 16 dorsal habitus 17 ventral habitus (arrow points to bifurcate claw III).

FIGURES 18 – 24. Protoribates robustior Jacot, 1937, New York, USA (18 – 20), Alberta, Canada (21 – 24). Adult (scale bars = 50 µm, except 20 = 10 µm) 18 frontal view 19 ventral habitus 20 lateral view palps, rutellum 21 dorsal view prodorsum 22 lateral habitus 23 light micrograph of porose area Aa (12 µm diameter) 24 discidium (60 µm long).

Tables

TABLE 1. Habitat distribution of Protoribates species in Alberta: the number of sites where each species has been collected.

	Fen	Bog	Moist forest	Mesic forest	Dry forest	Grassland	Treeless, disturbed
haughlandae sp. n.	18	4	1	4	-	-	4
robustior	-	-	-	3	5	7	4