Galumna flabellifera Hammer, 1958

Bayartogtokh, Badamdorj & Shimano, Satoshi, 2019, Contribution to the knowledge of Galumnidae (Acari: Oribatida) in the Oriental region, Zootaxa 4647 (1), pp. 368-377 : 371-373

Galumna flabellifera Hammer, 1958

( Fig. 2 )

Galumna flabellifera Hammer, 1958, p. 93 , fig. 116; Aoki 1964, p. 659, figs. 18–22; 1982, p. 186, fig. 8d; Mahunka 1978, p. 334, figs. 57–58; Al-Assiuty et al. 1985, p. 284, figs. 3 & 4.

Galumna flabellifera orientalis Aoki, 1965, p. 187 , figs. 97–100.

Galumna nuda Engelbrecht, 1972, p. 246 , figs. 12–22.

Pergalumna pyri Elbadry & Nasr, 1975, p. 145 .

Supplementary description. Body color dark brown; body covered by cerotegumental granules or small tubercles. Body length 307 µm, width of notogaster 211 µm; length of notogaster 224 µm. Rostrum rounded dorsally, but distinctly protruded in lateral view; inner rostral tooth (irt) of rostrum distinct ( Fig. 2B ). Lamellar (L) and sublamellar (S) ridges parallel, curving backwards ( Fig. 2C ). Rostral seta (ro) ∼ 24 µm, lamellar seta (le) ∼ 11 µm, both setae thin, smooth; interlamellar (in) and notogastral setae (c, la, lm, lp, h 1 - h 3, p 1 - p 3) represented by their alveoli. Sensillus relatively short, clavate, unilaterally barbed ( Fig. 2G ). Porose area Ad oval; exobothridial seta and porose area Al not evident. Anterior margin of notogaster almost straight, very slightly concave. Dorsophragma (D) slightly elongated longitudinally. Four pairs of notogastral porose areas, Aa, A 1, A 2 irregular round to oval, A 3 elongate oval; median pore (mp) well developed. All lyrifissures (ia, im, ip, ih, ips) and opisthonotal gland opening (gla) distinctly developed ( Fig. 2A, E ). Morphology of subcapitulum, palps and chelicerae typical for Galumna (e.g. see Ermilov & Corpuz-Raros 2016). Epimeral setae 1a, 3a well developed, 3b, 4b represented by their alveoli; other setae not evident. Discidium (dis) subtriangular. Circumpedal carina (cp) long, anteriorly extending beyond level of pedotectum II. Six pairs of genital (g 1 – g 6), two pairs of anal (an 1, an 2) and three pairs of adanal (ad 1 – ad 3) setae thin, smooth, 8–14 µm in length; seta ag represented by its alveolus. Adanal lyrifissure (iad) located close and parallel to anal aperture at level of ad 3 ( Fig. 2D ). Postanal porose area (Ap) elongate oval ( Fig. 2F ). Legs tridactylous, setation typical for family (e.g. see Ermilov & Corpuz-Raros 2016).

Material examined. One specimen (female): Raelkelat, Island of Babeldaob, Republic of Palau, from moss sample growing in a secondary forest, 7°28’59”N, 134°29’32”E, coll. S. Shimano, 17 December 2017.

Distribution. Initially, this species was described by Hammer (1958) from Bolivia, and later it was reported from Pacific and Indian islands, such as Laysan, Tahiti, Fiji and Mauritius ( Aoki 1964; Hammer 1971, 1972; Mahunka 1978), as well as Thailand ( Aoki 1965), South Africa ( Engelbrecht 1972), and several other areas of the tropical and subtropical regions ( Al-Assiuty 1985; Ermilov & Anichkin 2010; Ermilov & Tolstikov 2015 a, b). It is an inhabitant of the roots of grasses, mosses, soil and litter of the grasslands and various forests, seashore habitats, cliff sides and swampy marshes.

Remarks. The characters of the present material correspond well with those of the materials studied by Hammer (1958), Aoki (1964, 1982), Mahunka (1978) and Al-Assiuty et al. (1985). This is a morphologically quite variable species, and therefore, has been reported under several synonyms. This species is recorded for the first time from Palau.

Aoki (1965) described a subspecies, G. flabellifera orientalis from Thailand, but later he considered the differences mentioned by him as not sufficient for the subspecific segregation and therefore, synonymized G. flabellifera orientalis with the nominal subspecies ( Aoki 1982). In both lists by Subías (2004; online version 2019), and in Ermilov & Klimov (2017), this subspecies was listed as a valid taxon, which should be eliminated in their next update.

This species acts as an intermediate host of anoplocephalid tapeworms in sheep pastures ( Bayoumi et al. 1981; Balakrishnan & Haq 1984).

Figures

FIGURE 2. Adult of Galumna flabellifera Hammer, 1958.A—Dorsal view of body, legs not shown; B—Rostrum, dorso-frontal view, C—Anterior part of prodorsum, lateral view, D—Ventral view of body, legs not shown, E—Posterior part of notogaster, dorso-lateral view; F—Posterior view of notogaster; G—Sensillus, lateral view. A, B, C, D, E and F to same scale.