Oribatella texana, Behan-Pelletier, 2011

Behan-Pelletier, V. M., 2011, Oribatella (Acari, Oribatida, Oribatellidae) of eastern North America, Zootaxa 2973 (1), pp. 1-56 : 47-50

Oribatella texana sp. nov.

( Figs. 23E, 24 , 25 )

Material examined. Holotype: adult female. USA: Texas, Kendall Co., Guadeloupe State Park , 29’ 52.443N 98’ 29.139W, 3.iii.2007 ( VBP) from palmetto and oak litter; deposited in the CNC, type number 23958 . Paratypes: same data as holotype, 2 males; Texas , Bandera Co., Lost Maples State Natural Area , 29’ 48.984N 99’ 34.599W, 28.ii.2007 ( VBP) 1 female from wash of oak twigs; Uvalde Co. , Garner State Park, 29°34.090N 99°44.876, 2.iii.2007 ( VBP) 1 female, 1 male from mesic deep oak and cedar litter in depression; deposited in the CNC and RNC .

Diagnosis. Total length of adult 298–326 µm. Integument of notogaster, ventral and anal plates and coxisternal region micropunctate. Lamella (including cusp) about 108 µm long, cusp about 77 µm long, about 36 µm wide at level of insertion of seta le. Lamellar cusps fused posteromedially along length of about 24 µm, leaving prodorsum only visible through small oval opening, about 10 µm wide; translamella without tooth, about 10 µm at greatest width, 24 µm deep. Medial dens on lamellar cusp about 31 µm long, without teeth; lateral dens about 41 µm long with 3–4 teeth on lateral margin. Bothridial setae with barbed, narrowly fusiform head, rounded distally. Epimeral setae 3c about 19 µm long, thickly barbed, and 4c about 32 µm long, much thicker and more heavily barbed that other epimeral setae. Genital setae 1+5 or 2+4, 1 or 2 pairs of genital setae on anterior margin of genital plates. Ten pairs of long, curved, smooth to weakly barbed notogastral setae present; about 41 µm long, positioned so that lm posteromedial of Aa, and lp anterior of A1. Tarsi heterotridactylous.

Description. Adult. Dimensions: Mean total length: female (n = 2) 323 µm (320, 326); male (n = 4) 304 µm (range 298–322). Mean notogastral width: female (n =2) 223 µm (220, 226); male (n =3) 209 µm (range 206–216). Integument: Prodorsum, lateral of lamellae, notogaster, anal plate, pedotectum I with widely spaced micropuncta. Coxisternum, lamella, pedotectum I, tutorium and anterior of pteromorph with fine to very fine striae ( Fig. 25 ). Mentum and genital plate microtuberculate.

Prodorsum: Rostrum with medial crest dorsally; rostral margin undulating, with pair of minute dens laterally ( Fig. 25 ). Lamella (including cusp) about 108 µm long, cusp about 77 µm long, about 36 µm wide at level of insertion of seta le. Lamellar cusps converging then diverging or parallel anteromedially; fused posteromedially, leaving prodorsum only visible through small oval opening, about 10 µm wide; translamella without tooth, about 10 µm at greatest width, about 24 µm deep ( Figs. 23E arrow, 24). Medial dens on cusp about 31 µm long, without teeth; lateral dens about 41 µm long with 3–4 teeth ( Fig. 24 ), varying among specimens and on either side of same specimen. Setae ro about 53 µm long, strongly barbed along length, acuminate, curved anteromedially. Setae le about 58 µm long, thick, heavily barbed, tapered. Setae in about 103 µm long, thick (less so than le), heavily barbed, tapered; mutual distance of pair about 31 µm. Bothridial setae 72–77 µm long, with barbed, narrowly fusiform head, rounded to tapered distally, stalk short, smooth; head directed slightly anterodorsally ( Figs. 23E, 24 ). Exobothridial setae about 19 µm long, thin, barbed tapered.

Lateral aspect of podosoma: Genal tooth broad, subrectangular, with dens ventrodistally, with longitudinal ridge ventrally. Tutorium about 108 µm long, of which cusp about 50 µm long, rectangular, distal margin with 3–5 dens. Custodium about 29 µm long ( Fig. 25 ). Porose area Al about 10 µm in diameter.

Notogaster: Length subequal to width. Anterior margin undulating, convex lateral of bothridium, with 5–7 transverse ridges ( Fig. 24 ). Pteromorph with short ridges at anterior margin forming reticulate pattern; with small dens on anteroventral margin. Octotaxic system in form of 4 relatively small porose areas, about 8 µm in diameter. Ten pairs of long, curved, smooth to weakly barbed notogastral setae present; about 41 µm long, lm posteromedial of Aa, and lp anterior of A1 ( Fig. 24 ). Distance setae h 1 –h 1 subequal to distance p 1 –p 1, 14–16 µm. Subtriangular lenticulus present (not illustrated).

Ventral region: Epimeral setae 1a, 1b, 1c, 2a, 3a, 3b about 8–10 µm long, weakly barbed; 4a, 4b about 13 µm long, weakly barbed; 3c about 19 µm long, thickly barbed; 4c about 32 µm long, much thicker and more heavily barbed than other epimeral setae ( Fig. 25 ). Genital, aggenital, anal and adanal setae weakly barbed, about 8–10 µm long. Genital setae positioned in curved row, 1 or 2 pairs on anterior margin of plates. Postanal porose area oval, 12 x 6 µm.

Gnathosoma: Mentum with transverse carina anteriorly. Axillary saccule about 5 x 2 µm.

Legs: Setation (I to IV): trochanters, 1-1-2-1; femora, 5-5-3-2; genua, 3(1)-3(1)-1(1)-2; tibiae 4(2)-4(1)-3(1)- 3(1); tarsi, 20(2)-15(2)-15-12. Seta l” of genu I about 32 µm, l” of genu II about 29 µm. Tarsi heterotridactylous.

Etymology. The specific epithet ‘texana’ refers to the provenance of this species, Texas, USA.

Remarks. This species is similar to O. pusilla , but differs from the latter in depth of the translamella about 24 µm (15 µm deep in pusilla ), and epimeral seta 4c being thick and barbed (subequal in shape, but more distinctly barbed in pusilla ).

Distribution and Ecology. This species is known only from thick deciduous and coniferous litter from various parts of Texas.

Figures

FIGURE 24 Oribatella texana sp.nov., adult female, dorsal aspect, lenticulus and legs not illustrated. Scale bar = 50 µm.

FIGURE 25 Oribatella texana sp. nov., adult female, ventral aspect, legs not illustrated. Scale bar = 50 µm.