Pergalumna (Pergalumna) granulistriata Akrami, 2021

Akrami, Mohammad Ali & Rajabi, Monireh, 2021, A new oribatid mite of the genus Pergalumna (Acari: Oribatida: Galumnidae) from north-west of Iran, Persian Journal of Acarology 10 (2), pp. 127-135 : 128-132

Pergalumna (Pergalumna) granulistriata Akrami sp. nov. ( Figs. 1–10 )

Diagnosis

With typical characters of Pergalumna (Pergalumna) ; body size 537 × 374; basal half of the prodorsum with longitudinal striae and the rest granulate; rostrum with three distinct teeth: long median triangular tooth and two shorter lateral teeth; rostral and lamellar setae long, thin, nearly subequal in size, finely barbed unilaterally, interlamellar setae minute, but clearly visible, smooth; bothridial setae short, with finely barbed claviform head, rounded distally; dorsosejugal furrow developed; notogastral setae represented by their alveoli; five pairs of porose areas, Aa divided into two pairs: its anterior part very large, irregularly key-shaped, while posterior part very small, rounded; A 1 and A 2 nearly round, A 3 elongate oval; pteromorphs striated; postanal porose area large, elongate; median pore on the notogaster represented as single pore; notogastral lyrifissure im positioned far anteromediad of A 1, between setae lm and lp, more close to lm; genital plates with faint longitudinal striations.

Description

Measurements – Holotype (male): body length 537, width of notogaster 374, length of prodorsum 142; one paratype (male): nearly same as holotype.

Integument – Body color light brown; cuticle of body and legs with minute granules; marginal part of prodorsum around the bothridia with larger granules; pteromorphs with radiated ridges and fine striations; epimeral region with a few round sigillae.

Prodorsum ( Figs. 1, 3 , 4 ) – Rostrum with pronounced triangular central tooth and two smaller lateral teeth. Basal half of prodorsum with longitudinal striae and the rest microgranulate. Lamellar (L) and sublamellar (S) lines well developed. Rostra1 setae (ro, 53–57) thin, finely barbed unilaterally, inserted ventrally and well visible in dorsofrontal view. Lamellar setae (le, 51–55) thin, finely barbed unilaterally. Interlamellar setae (in, 13) minute, very thin and smooth. Exobothridial setae not observed. Bothridial setae (bs) with thin, smooth stalk (33–37) and finely barbed claviform head (34), distally rounded, directed inwards. Dorsosejugal porose areas (Ad, 22–27 × 7) elongate oval, located lateroposterior to alveolus of setae in. Bothridia (bo, 19 × 14) funnel-like, with wide openings, directed laterally.

Notogaster ( Figs. 1 , 7 ) – Notogaster distinctly widened posteriorly. Anterior notogastral margin well developed. Notogastral setae vestigial, 10 pairs of alveoli well discernable. Five pairs of porose areas, Aa divided into two pairs: anterior half (Aaa) (length 67–74) very large, irregularly key-shaped, obliquely oriented, its lateral part conspicuously widened, but medial part elongately narrowed, posterior half (Aap) (7 × 5) very small, rounded, located lateroposterior to alveolus of la; A 1 and A 2 (22–24 × 18–20) nearly subequal in size, round or slightly oval shape, A 3 (38 × 17) elongate oval; median pore (mp) present, consisting of single pore, located mid-distance of porose areas A 2. Lyrifissures ia, im and opisthonotal gland openings (gla) well developed, im inserted far anteromedially to A 1, between setal alveoli lm and lp, more close to lm, other notogastral lyrifissures was not observed; gla situated lateral to A 1 and h 3.

Gnathosoma ( Figs. 2 , 8 ) – Subcapitulum longer than wide, hypostomal setae a, m and h short, smooth. Palp typical for family, all setae except on tarsus finely barbed bilaterally, formula of setation: 0-2-1-3-10, including solenidion ω on tarsus. Chelicera typical for family.

Epimeral and podosomal region ( Fig. 2 ) – Pedotecta I and II, apodemes and discidia (dis) well developed. Circumpedal carina (cp) of medium length, thin, interrupted in level of insertions setae 4a. Only four pairs of epimeral setae observed.

Ano-genital region ( Figs. 2 , 5–7 ) – Anal and genital apertures situated far from each other, anal aperture (103 long, 114 wide) far larger than genital one (78 long and wide). Genital plates with six pairs of thin, short, smooth genital setae (g 1 -g 6) almost equal in size, g 1 and g 2 inserted on anterior margin of the plate; several short longitudinal striae inserted in inner margins of the plate. A pair of aggenital setae (ag) lateroposterior to genital plates; anal (an 1, an 2) and adanal (ad 1 -ad 3) setae smooth; ad 1 and ad 2 posterior to anal plates, ad 3 situated on paraanal position; adanal lyrifissure (iad) situated parallelly to anal aperture, little posterior to seta ad 3. Preanal organ (po) round. Postanal porose area (Ap, 80 × 13) large, elongate oval, narrowed laterally, situated posterior to anal plate.

Legs ( Figs. 9–10 ) – All legs tridactylous, with stronger median and slender lateral claws, all claws smooth. Morphology of leg segments and structure and setation of legs generally typical for species of Pergalumna . All setae on podomeres barbed, especially some of ventral setae heavily barbed. 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). Solenidiotaxy: I (1-2-2), II (1-1-2), III (1-1-0), IV (0-1-0). Homology of leg setae and solenidia indicated in Table 1.

Remarks In having the granulate-striate prodorsum, dentate rostrum with three distinct teeth (long triangular central tooth and two short lateral teeth), minute interlamellar setae, short, claviform bothridial setae, complete dorsosejugal furrow, diveded notogastral porose areas Aa, far anterior position of notogastral lyrifissure im, presence of median pore, very long postanal porose area and longitudinally striated genital plates, Pergalumna (P.) granulistriata Akrami sp. nov. is unique among the known species of Pergalumna .

Among Palaearctic species, P. formicaria ( Berlese, 1914) is most similar morphologically to the present new species. However, the former differs from the new species by the rounded rostrum, without teeth; smooth surface of prodorsum; elongate triangular porose areas Aa and smooth pteromorphs.

Material examined

Holotype (male): Taham village, Zanjan County, Zanjan Province, northwestern Iran, soil under poplar trees ( Populus sp. , Salicaceae ), 36° 50’ N, 48° 36’ E, 1900 m a.s.l., 12 Nov. 2012, coll. M. Rajabi. One paratype (male): same data as holotype.

Type deposition

The holotype and paratype are deposited in the collection of the Department of Plant Protection , School of Agriculture , Shiraz University, Shiraz, Iran .

Etymology The specific epithet " granulistriata " refers to the granulate-striate prodorsum in this species.

Figures

Figures 1–3. Pergalumna granulistriata Akrami sp. nov. – 1. Dorsal view of body; 2. Ventral view of body; 3. Bothridial seta. Scale bar (1 & 3 = 50 μm; 2 = 25 μm).

Figures 4–8. Pergalumna granulistriata Akrami sp. nov. – 4. Dorsofrontal view of prodorsum and anterior part of notogaster; 5. Genital plate; 6. Anal plate; 7. Notogastral porose areas (Aa, A1–3) and postanal porose area (Ap); 8. Palp. Scale bar (4–7 = 50 μm; 8 = 25 μm).

Figures 9–10. Pergalumna granulistriata Akrami sp. nov. – 9. Chaetotaxy of leg I; 10. Chaetotaxy of leg IV. Scale bar (50 μm).