Acrogalumna lanceolata, Bayartogtokh & Akrami, 2014

Bayartogtokh, Badamdorj & Akrami, Mohammad Ali, 2014, The soil mite family Galumnidae of Iran (Acari: Oribatida), Journal of Natural History 48 (15), pp. 881-917 : 889-893

Acrogalumna lanceolata sp. nov.

( Figures 4G–J , 5 , and 6)

Diagnosis

With typical characters of Acrogalumna (lamellar line absent; sublamellar line present; females without notogastral median pore, males with group of minute median pores); rostrum with pronounced triangular central carina and lateral carina with blunt tip; rostral and lamellar setae thin, smooth; interlamellar seta minute, but clearly visible; sensillus medium long, with finely barbed lanceolate head; all porose areas nearly round, subequal in size; median pore absent; postanal porose area small, round.

Measurements

Holotype: body length 320 µm, width of notogaster 246 µm; paratypes (n = 4): body length 310–325 (319) µm, width of notogaster 245–265 (255) µm.

Description

Integument. Body colour dark brown. Cuticle of body and legs with minute granules; notogaster, gnathosomal and epimeral regions with micortubercles; pteromorph with fine striations.

Prodorsum. Rostrum with pronounced triangular central carina and lateral carina with blunt tip, clearly seen in dorsofrontal view ( Figures 4G and 6A ). Rostral seta thin, 36–41 µm long, smooth, inserted ventrally and clearly visible in dorsofrontal view. Lamellar seta thin, 37–45 µm long, smooth ( Figure 6A ). Interlamellar seta minute, 6–10 µm long. Sensillus 57–65 µm long, with narrow stalk and finely barbed lanceolate head ( Figures 4H and 5A, B ). Lamellar line absent, sublamellar line well developed (Figure 65A). Dorsosejugal porose area small, round, located posterolaterad of seta in ( Figure 5A ).

Notogaster. Notogaster distinctly widened posteriorly, dorsosejugal furrow absent; pteromorph with fine striations. Notogastral setae short, thin, clearly discernable, 8– 12 µm long. All porose areas nearly round, subequal in size; median pore absent. Lyrifissures ia, im, ih, ip, ips and opisthonotal gland opening (gla) well developed ( Figures 4H–J , 5A and 6B ).

Gnathosoma . Subcapitulum longer than wide, with few microtubercles; hypostomal setae a, m and h 8–11 µm long, smooth ( Figure 5C ). Palp typical for family as shown in Pergalumna iunctiporosa sp. nov., all setae except on tarsus finely barbed, formula of setation: 0-2-1-3-10 including solenidion ω on tarsus. Chelicera same as in Allogalumna dentirostrata sp. nov., with few heavily sclerotized blunt teeth on fixed and movable digits; setae cha and chb long, barbed; Trägårdh’ s organ well developed, its proximal part clearly discernable.

Epimeral region. With few muscle sigillae; apodemes apo.1, apo.2, apo.sj, apo.3, circumpedal carina and discidium well developed. Only three pairs of epimeral setae of 6–8 µm length observed, setal formula: 1-0-1-1 ( Figure 5C ).

Ano-genital region. Anal aperture 61 µm long, 69 µm wide; genital aperture 45 µm long, 53 µm wide. Genital and aggenital setae well developed, thin, smooth, 12–16 µm long, aggenital seta (ag) 8 µm long; anal and adanal setae vestigial; adanal lyrifissure (iad) situated in paranal position, at level little posterior to seta an 2 ( Figure 5C ). Postanal porose area small, round ( Figures 5C and 6B ).

Legs. Structure and setation of legs typical for family as shown in the description of former species. Formula of setation, including famulus: I (1-4-3-4-20), II (1-4-3-4-15), III (1-2-1-3-15), IV (1-2-2-3-12), formula of solenidia I (1-2-2), II (1-1-2), III (1-1-0), IV (0-1-0).

Material examined

Holotype (female): Nashtarood, Mazandaran province, Northern Iran, 36°42 ʹ N, 51° 01 ʹ E, 20 m below sea level (b.s.l.), 9 April 2004, Coll. M. A. Akrami; four paratypes (females): same data as holotype; one paratype (female): Noor, Mazandaran province, Northern Iran, 36°47 ʹ N, 51°26 ʹ E, 17 m b.s.l., December 2001, Coll. A. Zahedi; one paratype (male): Nowshahr, begining of the Kandeloos road, Mazandaran province, Northern Iran, 36°39 ʹ N, 51°30 ʹ E, 19 m a.s.l., 10 April 2004, Coll. M. A. Akrami. The holotype and paratypes are deposited in the collection of the Department of Plant Protection , College of Agriculture, Shiraz University, Iran.

Remarks

Acrogalumna lanceolata sp. nov. is easily distinguished from other species of Acrogalumna in combination of following characters, namely: rostrum with pronounced triangular central carina and lateral carina with blunt tip; very short interlamellar seta; finely barbed lanceolate head of sensillus; well-developed notogastral setae, and nearly round porose area Aa. Most of species of Acrogalumna are either with setiform sensillus or long interlamellar seta, vestigial notogastral setae and rounded rostrum, in which they clearly differ from the present new species.

Among the known species of Acrogalumna , only Acrogalumna ventralis described by Willmann (1932) from Sumatra, later redescribed by Hammer (1972) from Tahiti, and Acrogalumna brevisetosa described by Bayartogtokh and Weigmann (2005) from Mongolia have minute interlamellar setae and fusiform sensillus.

However, Acrogalumna ventralis differs from the present new species in the smooth head of sensillus in contrast to the finely barbed head of sensillus in the new species; very minute lamellar seta in contrast to long seta le in the new species; absence of carina on rostrum as opposed to the distinct carina in the new species; vestigial epimeral, genital, aggenital and notogastral setae of l - and h - series rather than well-developed setae in the new species, and relatively larger body size.

The Mongolian species, Acrogalumna brevisetosa is distinguishable from the new species in the very narrow and smooth head of sensillus as opposed to widely lanceolate, barbed sensillus in the new species; porose area Aa is divided into two small parts rather than complete round porose area Aa in the new species; vestigial notogastral setae in contrast to well-developed setae in the new species; elongate-oval porose areas A 2 and A 3 rather than round porose areas in the new species, and much larger body size. Before this study there was no record of the genus Acrogalumna from Iran.

Etymology

The specific epithet “ lanceolata ” refers to the lanceolate shape of sensilli.

Ecology

This species is an inhabitant of lowland and forest soil, and most specimens were found in the soil under citrus fruits.

Figures

Figure 4. Morphological characters of different species. (A–F) Allogalumna dentirostrata sp. nov. (A) Anterior part of prodorsum; (B) gnathosomal, epimeral and genital regions; (C) pteromorph showing ridges on its cuticle; (D) left side of humeral region; (E) porose area Aa; (F) transversal ridges on notogastral margin. (G–J) Acrogalumna lanceolata sp. nov. (G) Rorstrum (arrow indicates central carina); (H) humeral region; (I) pteromorph; (J) porose areas, lyrifussure and opisthonotal gland opening. (K–N) Galumna triangulata sp. nov. (K) Lateral view of prodorsum; (L) lateral view of pteromorph and part of notogaster, showing transversal ridges; (M) rostrum (arrow indicates central carina); (N) lateral view of sensillus.

Figure 5. Acrogalumna lanceolata sp. nov. (A) Dorsal view of idiosoma; (B) lateral view of sensillus; (C) ventral view of idiosoma.

Figure 6. Acrogalumna lanceolata sp. nov. (A) Dorsofrontal view of prodorsum, partial; (B) posterior view of opisthonotum (postanal porose area, Ap is visible through notogaster).