Tegoribates subniger Ewing, 1917

Behan-Pelletier, Valerie M., 2017, Tegoribatidae of North America, with proposal of Protectoribates gen. nov., and new species (Acari, Oribatida, Tegoribatidae), Zootaxa 4337 (2) : 167-169

Tegoribates subniger Ewing, 1917

( Figs 8A–G , 22E )

Material examined: Holotype: adult, USA, “ Pine , Indiana, May 30, ’07 by myself. Under old waste lumber. M. in b. H.E. Ewing ”, housed in USNM, Type No. 2009427.

Other material examined: USA, Colorado, Moffat Co., Craig , 10.vii.1973 (R. Norton) 1 from roadside grass sod (RNC) ; New York, St. Lawrence Co., Yellow Lake , 44°20’33”N, 75°35’22”W, 8-2-2004, (R.B. Platt) 1 female from root-rich organic soil growing on dead log at air/water interface; Canada, Alberta, N of Hay River , 58.86497, -118.60268, 2007 ( ABMI) 4 adults from ABMI 2007 218SE, 2007 218SW, 2007 218NW; NW Embarras airport, 17.vi.2013 ( ABMI 238 NE) 1 adult .

Revised diagnosis. Total length 518-580. Lamella about 160 long. Lamellar seta thin, smooth, acuminate, about 40 long; mutual distance about 42. Seta in about 12 long, smooth, acuminate; mutual distance about 131. Bothridial seta narrowly fusiform, about 116 long. Tutorium about 133 long, with cusp distally, about 15 long. Octotaxic system expressed as tubules, positioned closely adjacent to setae; Ta adjacent to la, T1 adjacent to h3, T2 adjacent to h2, T3 adjacent to h1; tubules between 30 and 50 in length. Postanal porose area about 36 long and 3 wide.

Description. Adult. Total length 518-580. Total length of holotype from tip of rostrum to posterior of venter 518, total length from tip of lamella to posterior of venter 580 ( Ewing 1917), total length of second specimen to tip of lamella 576, length from tip of rostrum to posterior of venter 538; length (tip of rostrum to posterior of notogaster) specimens from Alberta: 530, 580.

Integument. Pteromorph, pedotectum I, gnathosoma , epimeres microtuberculate.

Prodorsum. Seta ro about 41 long, strongly barbed along length, acuminate, curved anteromedially. Lamella about 160 long, medially with concave indentation ( Fig. 8E ). Lamellar seta thin, smooth, acuminate, about 40 long; mutual distance about 42. Seta in about 12 long, smooth, acuminate; mutual distance about 131 ( Fig. 8E ). Bothridial seta narrowly fusiform, about 116 long. Seta ex or its alveolus, not evident. Dorsophragmata about 50 long ( Fig. 8E ).

Lateral of Podosoma. Pedotectum I pointed distally. Tutorium about 133 long, with cusp distally, about 15 long, covering insertion of seta ro. Ah expressed as circular porose area, about 18 in diameter ( Fig. 8E ). Custodium minute dens; circumpedal carina terminating medial to tubercle (3-5 long) at edge of acetabulum III, tubercle bearing seta 3c ( Fig. 8F ). Ridge extending anteriorly from tubercle, effacing on pedotectum I. Porose area Al absent.

Notogaster. Notogaster slightly longer than wide: 1.2:1; anterior margin straight. Lenticulus present. Octotaxic system expressed as tubules, positioned closely adjacent to setae ( Fig. 8D ); Ta adjacent to la, T1 adjacent to h3, T2 adjacent to h2, T3 adjacent to h1; tubules between 30 and 50 in length. Notogastral setae smooth, about 12 long, subequal in length.

Venter. Epimeral setae about 14–31 long, thin, smooth, acuminate, with 3c and 4c longest epimeral setae. Genital, aggenital, anal and adanal setae smooth; anterior 3 genital setae about 30. Postanal porose area about 36 long and 3 wide.

Gnathosoma . Small axillary saccule at base of palp, 7 x 2. Setae of chelicera barbed, acuminate; cha about 48 long, chb about 29 long. Solenidion and eupathidium acm of palptarsus lying parallel for most of length, bases separated by distance of about 1 ( Fig. 8G ). Length of seta m>a>h.

Legs. Setae l” of genua and tibiae I and II thicker than other setae on these segments, setose. Seta pv” of tarsus II strongly barbed. Tridactylous.

Remarks. This species and T. latirostris (body length of 600 according to Sellnick (1920), 620 according to Coggi (1900)) are the largest and most heavily melanized species of Tegoribates . Ewing (1917) described Tegoribates subniger as lacking lamellar, interlamellar and notogastral setae. These are present, but are difficult to discern on the type specimen which is preserved as a lateral slide mount ( Fig. 8A ). The type specimen was also studied by Woolley (1958) who noted the presence of notogastral setae, and lamellar setae and discussed the similarities and differences of Lepidozetes and Tegoribates . In his revision of Tegoribates he included both genera in Tegoribatidae ( Woolley 1965) .

This species and T. latirostris are the only known Tegoribates to express the octotaxic system as tubules; these are much longer in T. latirostris than in T. subniger based on figures in Grandjean (1953). Tegoribates subniger also differs from T. latirostris in the presence of interlamellar setae, based on illustrations of T. latirostris by Coggi (1900) and Kunst (1959). Other possible differences between T. subniger and T. latirostris are unknown, as examined putative specimens of T. latirostris from Central Europe represent an undescribed species.

Figures

FIGURE 8 A – H. Tegoribates subniger Ewing, differential interference contrast microscope images of adult. A, holotype specimen, Type No. 2009427, housed in USNM; B, lateral of prodorsum with arrow to taenidium; C, preanal organ indicated by arrow; D, region of tubule T 1, h 3 and gla, with small arrows to tubule and large arrow to its opening (3 layers); E, lamella (5 layers), with arrow to nerve canal for seta le, lateral of podosoma displaced so Ah visible, black arrow to fused dorsophragmata; F, ventral region showing discidium (dis) and circumpedal carina (cc), with arrow to minute custodium (3 layers); G, pedipalp (5 layers), with arrow to solenidion ω. Scale bars: A = 100 µm; C, D, F = 25 µm; E = 40 µm; G = 30 µm.

FIGURE 22. Differential interference contrast microscope images of adults; A – D, Tegoribates walteri sp. nov., A, part of prodorsum (4 layers) showing lamella, bothridium, bothridial seta, interlamellar seta, with arrow to fused dorsophragmata; B, hinged pteromorph (3 layers); C, coxisternal region showing custodium (arrow) and pedotectum II (3 layers); D, porose area Aa and surrounding muscle sigillae (5 layers). E, Tegoribates subniger Ewing, lateral of podosoma, showing elongated, bent femur I (indicated by arrow); F, G, Protectoribates occidentalis sp. nov., detail of preanal organ; H, Hypozetes laysanensis Aoki, detail of preanal organ; I, Tectoribates borealis Behan-Pelletier & Walter, detail of preanal organ. Scale bars: A, B, E = 25 µm; C, D = 20 µm.