Galumna tetraporosa, Ermilov, Sergey G., Martens, Jochen & Tolstikov, Andrei V., 2014

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

Taxon classification Animalia Oribatida Galumnidae

Galumna tetraporosa sp. n. Figs 1-5

Diagnosis.

Body size: 913-979 × 730-763. Rostrum pointed. Rostral and lamellar setae of medium size. Interlamellar setae represented by alveolus. Bothridial setae long, clavate, barbed. Lamellar and sublamellar lines divergent in medio-distal part. Anterior notogastral margin not developed. Notogaster with five pairs of small, rounded porose areas, Aa divided into two parts. Median pore absent. Aggenital and ano-adanal setae minute. Postanal porose area present, elongated.

Description.

Measurements. Body length: 962 (holotype), 913-979 (two paratypes); notogaster width: 730 (holotype), 730-763 (two paratypes).

Integument. Body color black to dark brown. Body surface smooth. Pteromorphs with poorly visible radiate wrinkles.

Prodorsum. Rostrum with strong tooth (12-20). Rostral setae (ro, 53-65) setiform, barbed. Lamellar setae (le, 65-77) setiform, little thicker and less barbed than rostral setae. Interlamellar setae absent, represented alveolus. Bothridial setae (ss, 114-123) with long stalk and shorter, barbed clavate head. Exobothridial setae absent. Porose areas Ad present, elongate oval (24-32 × 12-16), but visible only in dissected specimen. Lamellar lines (L) curving backwards; sublamellar lines (S) parallel in basal part and divergent in medio-distal part to lamellar lines.

Notogaster. Anterior notogastral margin not developed. Dorsophragmata (D) of medium size, elongated. Notogastral setae represented by 10 pairs of alveoli. Five pairs of small, rounded porose areas with distinct borders: Aa divided into two porose areas - smaller lateral (8-16) and larger medial (20-28); A1 (12-16) and A2 (16-28) located close to each other; A3 (24-36) usually largest. Alveoli la inserted posteriorly to Aa. Lyrifissures im located anteriorly or antero-laterally to A1. Opisthonotal gland openings (gla) located antero-laterally to A2. Median pore absent.

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 (196 × 192). Subcapitular setae setiform, slightly barbed; a (32-36) longer, more barbed and thicker than m (24) and h (16-20). Two pairs of adoral setae (or1, or2, 20) setiform, barbed. Palps (143) with setation 0 –2–1–3– 9(+ω). Solenidion straight, thickened, blunt-ended, attached to eupathidium. Chelicerae (246) with two barbed setae; cha (94) longer than chb (53). Trägårdh’s organ distinct.

Epimeral and lateral podosomal regions. Apodemes (1, 2, sejugal, 3) well visible. Four pairs of epimeral setae (1b, 3b, 4a, 4b) observed ventrally, all setiform, thin, smooth, similar in length (24-32). Discidia (dis) triangular, circumpedal carinae (cp) distinct.

Anogenital region. Six pairs of genital setae (g1-g6, 24-28) setiform, thin, smooth. Anterior edge of genital figs with three setae. One pair of aggenital (ag), two pairs of anal (an1, an2) and three pairs of adanal (ad1-ad3) setae minute, similar in length (4). Adanal setae ad3 inserted laterally to adanal lyrifissures iad. Postanal porose area (Ap) elongated (36-49 × 8-12).

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.

Type deposition.

The holotype and one paratype are deposited in the collection of the Senckenberg Institution Frankfurt, Germany; one paratype is deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.

Etymology.

The specific name “tetraporosa” refers to the four notogastral porose areas Aa.

Remarks.

In having the pointed rostrum and bothridial setae with well developed head, Galumna tetraporosa sp. n. is most similar to Galumna tokyoensis Aoki, 1966 from the eastern Palaearctic region and Galumna valida Aoki, 1994 from the Pacific Islands. However, it clearly differs from both by the absence of interlamellar setae (versus long in Galumna tokyoensis and Galumna valida ) and the presence of two pairs of notogastral porose areas Aa (versus one pair in Galumna tokyoensis and Galumna valida ).