Galumna granalata Aoki, 1984

Ermilov, Sergey G., Martens, Jochen & Tolstikov, Andrei V., 2014, The genus Galumna in Nepalese oribatid mite fauna, with notes on systematic placement of some species (Acari, Oribatida, Galumnidae), ZooKeys 438, pp. 33-44 : 34-37

Taxon classification Animalia Oribatida Galumnidae

Galumna granalata Aoki, 1984 Figs 6-10

Description.

Measurements. Body length: 431-464 (eight specimens); notogaster width: 332-356 (eight specimens).

Integument. Body color light brown. Body surface smooth. Pteromorphs with radiate wrinkles and small (length up to 12), elongate, grain-shaped tubercles. Wrinkles and tubercles very poorly visible in some specimens.

Prodorsum. Rostrum rounded. Rostral (28-32) and lamellar (16-20) setae setiform, thin, smooth, often not visible in dorsal view. Interlamellar setae minute (4). Bothridial setae (57-65) with long stalk and shorter, barbed, clavate head. Exobothridial setae absent. Porose areas Ad present, elongate oval (10-16 × 4-6). Lamellar and sublamellar lines parallel, curving backwards.

Notogaster. Anterior notogastral margin well developed, convex. Dorsophragmata of medium size, triangular. Notogastral setae represented by 10 pairs of alveoli. Four pairs of rounded porose areas with distinct borders: Aa (16-20) larger than A1 (12-16), A2 (8-10) and A3 (10-16). Alveoli la inserted posteriorly to Aa. Lyrifissures im located between lm and lp. Opisthonotal gland openings located laterally to A1. Median pore present, located little posterior to the virtual line connecting porose areas A1.

Gnathosoma. Generally, morphology of subcapitulum, palps and chelicerae typical for most Galumnidae (for example, see Ermilov and Anichkin 2010, 2011; Ermilov et al. 2011). Subcapitulum little longer than wide (106 × 98). Subcapitular setae setiform, smooth; a (24) longer and little thicker than m (12) and h (16). Two pairs of adoral setae (10) setiform, slightly barbed. Palps (86) with setation 0 –2–1–3– 9(+ω). Solenidion straight, thickened, blunt-ended, attached to eupathidium. Chelicerae (131) with two barbed setae; cha (49) longer than chb (28). Trägårdh’s organ distinct.

Epimeral and lateral podosomal regions. Apodemes (1, 2, sejugal, 3) well visible. Three pairs of epimeral setae (1a, 3b, 4a) observed ventrally, all setiform, thin, smooth; 1a and 3b (12-16) longer than 4a (8). Discidia triangular, circumpedal carinae distinct.

Anogenital region. Six pairs of genital setae (12-16) setiform, thin, smooth. Anterior edge of genital figs with three setae. One pair of aggenital (8), two pairs of anal (4) and three pairs of adanal (4) setae minute. Adanal setae ad3 inserted laterally to adanal lyrifissures iad. Postanal porose area (Ap) very small, rounded (6-12). Ovipositor of typical morphology for Galumnidae ( Ermilov 2010): elongate, narrow (183 × 41). Length of lobes 77, length of cylindrical distal part 106. Setae setiform, smooth, ψ 1 ≈ τ 1 (36-41) longer than ψ 2 ≈ τa ≈ τb ≈ τc (16-20). Six setae k short (6).

Legs. Generally, morphology of leg segments, setae and solenidia typical for most Galumnidae (for example, see Ermilov and Anichkin 2010, 2011; Ermilov et al. 2011). Formulae of leg setation and solenidia: I (1 –4–3–4– 20) [1 –2– 2], II (1 –4–3–4– 15) [1 –1– 2], III (1 –2–1–3– 15) [1 –1– 0], IV (1 –2–2–3– 12) [0 –1– 0]; homology of setae and solenidia indicated in Table 1.

Remarks.

Galumna granalata distinctly differs from other species of the genus Galumna by the presence of grain-shaped tubercles (granules in opinion of Aoki) on pteromorphs. The present Nepalese specimens of this species are morphologically and in general appearance similar to the Japanese specimens ( Aoki 1984). Only one difference is that the body body size larger (431-464 × 332-356 versus 310-330 × 250-260 in Japanese specimens). We believe these differences represent intraspecific (e.g. geographical) variability.