Galumna (Neogalumna) longilineata, Ermilov, Sergey G. & Anichkin, Alexander E., 2014

Ermilov, Sergey G. & Anichkin, Alexander E., 2014, Taxonomic study of oribatid mites (Acari, Oribatida) of Bi Dup — Nui Ba National Park (southern Vietnam), Zootaxa 3834 (1), pp. 1-86 : 72-77

Galumna (Neogalumna) longilineata sp. nov.

( Figures 50–53 )

With characters of the genus Galumna Heyden, 1826 as summarized by Ermilov et al. (2013 d) and subgenus Galumna (Neogalumna) Hammer, 1973 as summarized by Hammer (1973) for the genus Neogalumna Hammer, 1973 .

Diagnosis. Body size 431–448 × 282–348. Prodorsal setae well developed, setiform, barbed. Bothridial setae setiform, ciliate. Lamellar lines straight, reaching insertions of rostral setae. Four pairs of porose areas present, circular or oval. Median pore absent. Medial part of genital plates with longitudinal stria. Postanal porose area oval.

Description. Measurements. Body length 431 (holotype: female), 431–448 (three paratypes: two females and one male); body width 298 (holotype), 282–348 (three paratypes).

Integument. Body color yellowish-brown. Body surface smooth. Pteromorphs with well developed radiate wrinkles. Some stria located posteriorly to the genital aperture. Medial part of genital plates with longitudinal stria.

Prodorsum. Rostrum widely rounded. Rostral (36–41), lamellar (57–61) and interlamellar (69–82) setae setiform, barbed. Bothridial setae (98–127) longest on prodorsum, setiform, with cilia unilaterally. Exobothridial setae absent. Lamellar (L) and sublamellar lines distinct. Lamellar lines straight, long, reaching insertions of rostral setae. Sublamellar lines typical for Galumna : long, curving backwards. Porose areas Ad oval, transverse elongate (20–24 × 8).

Notogaster. Anterior notogastral margin developed. Dorsophragmata very small. Notogastral setae represented by ten pairs (additionally c x present) of alveoli (eleventh pair located on pteromorphs). Four pairs of porose areas (Aa, 26–36, A1, 12–18, and sometimes A3, 16–20, circular; A2, 12–16 × 8–12 and A3, 20–24 × 12–16, oval), with distinct borders. Alveoli of setae la located posteriorly to Aa. Lyrifissures im located between lm and A1. Opisthonotal gland openings located laterally to A1. Median pore absent in all specimens.

Gnathosoma. Subcapitulum longer than wide (98–106 × 90–98). Subcapitular setae setiform, slightly barbed; a (18–20) longer than m and h (both 8–12). Two pairs of adoral setae (6–8) setiform, slightly barbed. Palps (82) with setation 0–2–1–3–9(+ω). Solenidion little longer than half of palptarsus length, straight, thickened, blunt-ended, attached to eupathidium. Chelicerae (118–127) with two barbed setae; cha (36–45) longer than chb (24–28). Trägårdh’s organ distinct.

Epimeral and lateral podosomal regions. Apodemes (1, 2, sejugal, 3) well visible. Four pairs of thin, smooth epimeral setae observed ventrally; all (1a, 3b, 4a, 4b) similar in length, short (8). Discidia triangular, pointed. Circumpedal carinae distinct.

Anogenital region. Six pairs of genital (g 1, g 2, 12–16; g 3– g 6, 8), one pair of aggenital (8), two pairs of anal (8) and three pairs of adanal (8) setae thin, smooth. Anterior edge of genital plates with two setae. Adanal lyrifissures iad located antero-laterally to adanal setae ad 3. Postanal porose area oval (24 × 12–16).

Legs. Tridactylous; claw of each leg smooth. 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]; homologies of setae and solenidia indicated in Table 12.

Type material. Collection data for holotype (female): locality 3 (soil); collection data for three paratypes (two females and one male): locality 3 (soil).

Type deposition. The holotype is deposited in the collection of the Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia; one paratype in deposited in the collection of the Siberian Zoological Museum, Novosibirsk, Russia; two paratypes are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.

Etymology. The specific name “ longilineata ” refers to the long lamellar lines.

Remarks. The genus Neogalumna was proposed by Hammer (1973) with Neogalumna antenniger Hammer, 1973 as a type species. It is morphologically similar to the genus Galumna . The main morphological difference between these two genera is location of adanal lyrifissures: removed from anal plates, located laterally or anterolaterally to adanal setae ad 3 in Neogalumna versus located very close to anal plates, medially, antero-medially or postero-medially to adanal setae ad 3 in Galumna . However, this character state is inherent for some other taxa in the Galumnoidea (for example, Globogalumna Balogh & Balogh, 1990 , some Heterogalumna Balogh, 1960 ). Thus, we consider that Neogalumna should be included as the subgenus in the genus Galumna : Galumna (Neogalumna) Hammer, 1973 stat. n. Hence, all known species of Neogalumna also should be combined: G. (N.) aethiopica ( Mahunka & Mahunka-Papp, 2009) comb. n., G. (N.) antenniger ( Hammer, 1973) comb. n., G. (N.) araujoi ( Perez-Íñigo & Baggio, 1994) comb. n., G. (N.) curviporosa ( Balakrishnan, 1986) comb. n., G. (N.) longiporosa ( Liang, Yang & Tang, 2014) comb. n., G. (N.) seniczaki ( Ermilov & Anichkin, 2010) comb. n.

Similarly, the situation on taxonomic status of the genus Globogalumna is presented. It was proposed by J. & P. Balogh (1990) with Allogalumna globulifera Balogh & Mahunka, 1978 as a type species. It is morphologically similar to the genus Allogalumna , but adanal lyrifissures removed from anal plates in Globogalumna versus located very close to anal plates in Allogalumna . Thus, we consider that Globogalumna should be included as the subgenus in the genus Allogalumna : Allogalumna (Globogalumna) Balogh & & Balogh stat. n. Hence, all known species of Globogalumna also should be combined: A. (G.) biporosa (Ermilov & Anichkin, 2012) (d) comb. n., A. (G.) globulifera ( Balogh & Mahunka, 1978) comb. n.

The subgenus Galumna (Neogalumna) Hammer, 1973 comprises six species, which are distributed in the Oriental and Neotropical regions, north-eastern China, Polynesia and Kenya (data summarized by Subías 2004, updated 2014).

In having the combination of long interlamellar setae, setiform and ciliate bothridial setae, presence of anterior margin of notogaster, presence of four pairs of circular porose areas and striate medial parts of genital plates, Galumna (Neogalumna) longilineata sp. nov. is similar to Galumna (Neogalumna) seniczaki ( Ermilov & Anichkin, 2010) from Vietnam. However, it clearly differs from the latter by the presence of long lamellar lines, reaching the insertions of rostral setae (versus short, clearly not reaching the insertions of rostral setae in G. (N.) seniczaki ), lamellar setae distinctly longer than rostral setae (versus both similar in G. (N.) seniczaki ) and larger porose area Aa (diameter 26–36 versus 16–20 G. (N.) seniczaki ).

Figures

FIGURE 50. Galumna (Neogalumna) longilineata sp. nov., adult: A—dorsal view; B—lateral view of prodorsum and anterior part of notogaster (gnathosoma and legs not illustrated). Scale bar 100 Μm.

FIGURE 51. Galumna (Neogalumna) longilineata sp. nov., adult: A—ventral view (gnathosoma and legs not illustrated); B—posterior view of notogaster and postanal porose area. Scale bar 100 Μm.

FIGURE 52. Galumna (Neogalumna) longilineata sp. nov., adult: A—rostrum; B—bothridial seta; C—pteromorph; D—porose area Aa; E—porose area A 1; F—porose area A 2; G—porose area A 3; H—porose area Ap; I—subcapitulum, right half, ventral view; J—palptarsus; K—chelicera (without posterior part); L—genital plate, right; M—anal plate, right, and adanal setae. Scale bar (A) 100 Μm; scale bar (B, I, K – M) 20 Μm; scale bar (C) 50 Μm, scale bar (D – H, J) 10 Μm.

FIGURE 53. Galumna (Neogalumna) longilineata sp. nov., adult: A—leg II, without trochanter, left, antiaxial view; B—leg IV, right, antiaxial view. Scale bar 20 Μm.