Galumna (Galumna) bidentatirostris, Ermilov, Sergey G., Sandmann, Dorothee, Klarner, Bernhard, Widyastuti, Rahaju & Scheu, Stefan, 2015

Ermilov, Sergey G., Sandmann, Dorothee, Klarner, Bernhard, Widyastuti, Rahaju & Scheu, Stefan, 2015, Contributions to the knowledge of oribatid mites (Acari, Oribatida) of Indonesia. 3. The genus Galumna (Galumnidae) with description of a new subgenus and seven new species, ZooKeys 539, pp. 11-51 : 14-19

Taxon classification Animalia Oribatida Galumnidae

Galumna (Galumna) bidentatirostris sp. n. Figs 10, 11, 12-13, 14-19

Diagnosis.

Body size: 564-664 × 448-514. Rostrum bidentate. Lamellar lines directed to lateral margins of prodorsum. Rostral setae curved medio-downwards. Lamellar setae shortest, interlamellar setae longest on prodorsum. Bothridial setae long, with dilated unilaterally, slightly barbed distally head. Anterior notogastral margin developed. Four pairs of oval porose areas on notogaster. Median pore and postanal porose area present.

Description.

Measurements. Body length: 581 (holotype: male), 564-664 (five paratypes: two females and three males); notogaster width: 464 (holotype), 448-514 (five paratypes). Without sexual dimorphism.

Integument. Body color brown. Body surface, pteromorphs, subcapitular mentum, genital and anal plates punctate.

Prodorsum. Rostrum bidentate, teeth (t) strong. Lamellar and sublamellar lines distinct, curving backwards, slightly divergent in distal parts, lamellar lines directed to lateral margins of prodorsum. Rostral setae (41-49) indistinctly dilated basally and curved specifically medio-downwards, smooth. Lamellar setae (24-32) setiform, thin, slightly barbed. Interlamellar setae (69-73) setiform, straight, barbed. Bothridial setae (155-176) with long, smooth stalk and short, elongated, dilated unilaterally, slightly barbed distally head. Exobothridial setae and their alveoli absent. Porose areas Ad oval, transversally oriented (12-16 × 4-6).

Notogaster. Anterior notogastral margin developed. Dorsophragmata elongated longitudinally. Four pairs of porose areas oval, with distinct margins: Aa (36-45 × 24-32) larger than A1, A3 (32-36 × 20-24) and A2 (16-24 × 12-20). Notogastral setae represented by 10 pairs of alveoli, la inserted posteriorly to Aa. Median pore present in all specimens, located between A2. All lyrifissures distinct, im and opisthonotal gland openings located laterally to A1.

Gnathosoma. Morphology of subcapitulum, palps and chelicerae typical for Galumna (Galumna) (see Engelbrecht 1969; Ermilov and Anichkin 2010). Subcapitulum size: 151-155 × 143-147. Subcapitular setae setiform, similar in thickness approximately, barbed, h (16) shorter than m (20-24) and a (24-28). Two pairs of adoral setae (16) setiform, hook-like distally, barbed. Palps (102-110) with typical setation: 0 –2–1–3– 9(+ω). Axillary sacculi distinct. Chelicerae (184-188) with two setiform, barbed setae; cha (65-69) longer than chb (41-45). Trägårdh’s organ long, tapered.

Epimeral and lateral podosomal regions. Anterior tectum of epimere I smooth. Apodemes 1, 2, sejugal and 3 well visible. Setal formula: 1 –0–1– 2. Setae 1a and 3b (24-28) setiform, barbed; 4a and 4b (8) thin, smooth. Pedotecta II rounded anteriorly in ventral view. Discidia triangular. Circumpedal carinae distinct, little not reaching the insertions of setae 3b.

Anogenital region. Six pairs of genital (g1, g2, 14-18; g3-g6, 6-8), one pair of aggenital (8-12), two pairs of anal (8-12) and three pairs of adanal (8-12) setae thin, smooth. Two setae on anterior edge of each genital plate. Adanal setae ad3 inserted laterally to adanal lyrifissures. Postanal porose area elongated, transversally oriented (36-45 × 8-12).

Legs. Morphology of leg segments, setae and solenidia typical for Galumna (Galumna) (see Engelbrecht 1969; Ermilov and Anichkin 2010). Tridactylous, claws smooth. Formulas of leg setation and solenidia are similar to Galumna (Atypicogalumna) corpuzrarosae sp. n. (Table 1). Solenidion φ of tibiae IV inserted dorsally at about 2/3 length of segment.

Material examined.

Holotype (male) and five paratypes (two females and three males): Indonesia, Sumatra, Harapan landscape, oil palm plantation, research site HO1, 01°54'35.6"S, 103°15'58.3"E, 81 m a.s.l., in upper soil layer (0-5 cm). All specimens were collected by Bernhard Klarner (Nov. 2013) and identified and collected to morphospecies level by Dorothee Sandmann.

Type deposition.

The holotype is deposited in LIPI (Indonesian Institute of Science) Cibinong, Indonesia; two paratypes are deposited in the collection of the Senckenberg Museum, Görlitz, Germany; three paratypes are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.

Etymology.

The specific name bidentatirostris refers to the bidentate rostrum.

Remarks.

Galumna (Galumna) bidentatirostris sp. n. is morphologically most similar to Galumna (Galumna) gibbula Grandjean, 1956 from the Mediterranean (see Grandjean 1956) in having four pairs of oval porose areas on notogaster, long bothridial setae with elongated, unilaterally head, similar relative lengths of prodorsal setae (in> ro> le), median pore and elongated postanal porose area. However, the new species differs from the latter by the presence of bidentate rostrum (vs. without teeth in Galumna (Galumna) gibbula ), rostral setae curved medio-backwards (vs. not curved in Galumna (Galumna) gibbula ), anterior notogastral margin (vs. not developed in Galumna (Galumna) gibbula ), lamellar lines directed to lateral margins of prodorsum (vs. directed to insertions of rostral setae), and the absence of an apophysis in the posterior part of the notogaster (vs. present in Galumna (Galumna) gibbula ).