Galumna (Cosmogalumna) ekaterinae, Ermilov & Friedrich, 2016

Ermilov, S. G. & Friedrich, S., 2016, New species and records of Galumna (Acari, Oribatida, Galumnidae) from Peru, Acarologia 56 (2), pp. 183-193 : 188-191

Galumna (Cosmogalumna) ekaterinae n. sp.

( Figures 3-4 )

Diagnosis – Body size: 266 – 315 × 221 – 265. Anterior part of notogaster with narrow, transversely oriented reticulate cells. Surface of anogenital region and medio-posterior part of notogaster with cerotegumental ridges not forming clear reticulate pattern. Transversely striate band located anterior to genital aperture. Bothridial setae fusiform, truncate distally, smooth. Three pairs of small, round porose areas developed on notogaster, A2 absent. Setal alveoli c located in posterior half of pteromorph. Median pore and postanal porose area present. Aggenital setae absent.

Description — Measurements – Body small: length 274 (holotype: female), 266 – 315 (11 paratypes: six females and five males); notogastral width 225 (holotype), 221 – 265 (11 paratypes). Without sexual dimorphism.

Integument — Body brown, covered by dense microgranular cerotegument (diameter of granules less than 1). Anterior part of notogaster with reticulate pattern, cells very narrow, transversely oriented. Surface of anogenital region and medioposterior part of notogaster with cerotegumental ridges forming vaguely reticulate pattern, but complete cells rarely formed. Cerotegument on pteromorphs represented by short, separated ridges. Transverse bands of striae located anterior to genital aperture and posterior to anal aperture.

Prodorsum — Rostrum slightly protruding, broadly rounded. Lamellar and sublamellar lines thin, parallel, curving backwards. Rostral (24 – 26) and lamellar (10 – 12) setae setiform, indistinctly barbed, directed antero-medially; ro thicker than le. Interlamellar setae (2) minute, inconspicuous. Bothridial setae (53 – 57) smooth, fusiform, with long, smooth stalk and shorter, distally truncate head. Exobothridial setae and their alveoli absent. Porose areas Ad not found.

Notogaster — Anterior notogastral margin developed. Dorsophragmata short, slightly elongated longitudinally. Three pairs of porose areas (Aa, A1, A3) small (8 – 10), rounded, with distinct borders, A2 absent. Notogastral setae represented by 10 pairs of alveoli, c located in posterior half of pteromorphs, la located postero-lateral to Aa, h 3 anterior to A1. Median pore present, located posterior to virtual line connecting porose areas A1. All lyrifissures distinct, im anterior to A1. Opisthonotal gland openings located lateral to A1.

Gnathosoma — Morphology of subcapitulum, palps and chelicerae typical for Galumna (Cosmogalumna) (see Ermilov et al. 2011; Ermilov and Anichkin 2013). Subcapitulum size: 69 – 77 × 57 – 69. Subcapitular setae thin, smooth, a (8) longer and slightly thicker than m (6) and h (6). Two pairs of adoral setae (4) minute. Length of palps: 45 – 49. Axillary sacculi small, slightly elongated. Length of chelicerae: 73 – 86. Cheliceral setae setiform, barbed, cha (28) longer than chb (16).

Epimeral and lateral podosomal regions — Anterior tectum of epimere I smooth. Setal formula: 2-0-2-3; setae short, smooth, 3c and 4c (8) longer than 3b (6) and 1a, 1c, 4a and 4b (2 – 4). Pedotecta II trapezoid, rounded distally in ventral view. Discidia sharply triangular. Circumpedal carinae directed to pedotecta I.

Anogenital region — Six pairs of genital (g 1 - g 2, 6; g 4 - g 6, 4), two pairs of anal (4) and three pairs of adanal (4) setae thin, smooth; g 1 - g 2 on anterior edge of genital plate. Aggenital setae and their alveoli absent. Adanal lyrifissures located close and parallel to anal plates. Setae ad 3 inserted lateral to iad. Postanal porose area elongated, transversely oriented (16 × 4 – 6).

Legs — Morphology of subcapitulum, palps and chelicerae typical for Galumna (Cosmogalumna) (see Ermilov et al. 2011; Ermilov and Anichkin 2013). Median claw thicker than laterals, all smooth. Formulas 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]; homology of setae and solenidia indicated in Table 1 . Solenidion ’ of tibiae IV inserted dorsally at about 2/3 length of segment.

Material examined — Holotype (female) and 11 paratypes (six females and five males): see "Mate- rial and methods" section. Type deposition — The holotype is deposited in the collection of the Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru; three paratypes are deposited in the collection of the Bavarian State Collection of Zoology, Mu- nich, Germany; three paratypes are deposited in the collection of the Senckenberg Institution Frankfurt, Germany; five paratypes are deposited in the col- lection of the Tyumen State University Museum of Zoology, Tyumen, Russia. Etymology — The specific name is dedicated to our friend and colleague, acarologist, Dr. Ekate- rina A. Sidorchuk (Paleontological Institute, Rus- sian Academy of Sciences, Moscow, Russia).

Remarks — The new species differs from all other representatives of Galumna (Cosmogalumna) by the truncate (vs. rounded) head of the both- ridial setae, setal alveoli c located in posterior half of pteromorphs (vs. in anterior half) and the absence (vs. presence) of aggenital setae. The new species is morphologically most simi- lar to Galumna (Cosmogalumna) areticulata Ermilov, Sandmann, Klarner, Widyastuti and Scheu, 2015 from Indonesia (see Ermilov et al. 2015) in the ab- sence of distinct reticulate ornamentation on the notogaster and anogenital region, however, it dif- fers from the latter (in addition to characters listed above) by the presence of three pairs (vs. four) of notogastral porose areas and the presence (vs. ab- sence) of epimeral setae 3 c and 4 c.

Figures

FIGURE 3: Galumna (Cosmogalumna) ekaterinae n. sp.: A – dorsal view; B – anterior part of body, lateral view (gnathosoma and legs not illustrated). Scale bar 100 µm.

FIGURE 4: Galumna (Cosmogalumna) ekaterinae n. sp.: A – ventral view (gnathosoma and legs not illustrated); B – posterior view. Scale bar 100 µm.