New species and records of Galumna ( Acari , Oribatida , Galumnidae ) from Peru

Two new species of oribatid mites of the genus Galumna (Oribatida, Galumnidae) are described based on specimens from upper soil and leaf litter in a primary evergreen lowland rainforest in Amazonian Peru. Galumna (Galumna) parazeucta n. sp. is morphologically most similar to Galumna (Galumna) neonominata Subías 2004 and G. (Galumna) pterolineata Hammer, 1972, but differs by the presence of strongly elongated notogastral porose areas Aa and A3. Galumna (Cosmogalumna) ekaterinae n. sp. is morphologically most similar to Galumna (C.) areticulata Ermilov, Sandmann, Klarner, Widyastuti and Scheu, 2015, but differs by the presence of three pairs of notogastral porose areas and epimeral setae 3c and 4c. The subgenus Galumna (Cosmogalumna) and species Galumna (Galumna) nuda Engelbrecht, 1972 are recorded in the Neotropical region for the first time; two species – Galumna (G.) angularis Jeleva, Scull and Cruz, 1984 and Galumna (G.) laselvae Balogh 1997 – are recorded in Peru for the first time.


INTRODUCTION
This work is a part of our continuing study of the Peruvian fauna of oribatid mites (Ermilov and Gwiazdowicz 2015;Ermilov and Friedrich 2016) and includes data on the genus Galumna Heyden, 1826 (Acari, Oribatida, Galumnidae).
Among the oribatid mite material collected during the German Expedition to Amazonian Peru in 2013 were representatives of six species of Galumna (two are new for science) belonging to two subgenera: Galumna (Galumna) Heyden, 1826 and G. (Cosmogalumna) Aoki, 1988.The main goal of this paper is to describe and illustrate two new species and present data on the records and overall known distribution of the registered taxa.
Methods -Specimens were mounted in lactic acid on temporary cavity slides for measurement and illustration.Body length was measured in lateral view, from the tip of the rostrum to the posterior edge of the ventral plate.Notogastral width refers to the maximum width in dorsal aspect.Lengths of body setae were measured in lateral aspect.All body measurements are presented in micrometers.Formulas for leg setation are given in parentheses according to the sequence trochanterfemur-genu-tibia-tarsus (famulus included).Formulas for leg solenidia are given in square brackets according to the sequence genu-tibia-tarsus.

DESCRIPTIONS
Integument -Body brown, covered by dense microgranular cerotegument (diameter of granules less than 1).Surface of dorsal and ventral sides, pteromorphs and subcapitular mentum striate; striae of anogenital region and median part of epimeral region short, those of other body regions long.
Material examined -Holotype (male) and two paratypes (both males): see "Material 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; two paratypes are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.
Etymology -The specific name parazeucta refers to the similarity between the new species and the species Erogalumna zeucta Grandjean, 1964.Remarks -The new species is morphologically most similar to Galumna (Galumna) neonominata Subías 2004 (=Galumna clavata Pérez-Íñigo and Baggio 1991)1 from Brazil (see Pérez-Íñigo and Baggio 1991) and G. (Galumna) pterolineata Hammer, 1972 from Tahiti (see Hammer 1972) in having a striate body surface.However, it differs from both by the presence of strongly elongated (vs.oval) notogastral porose areas Aa and A3.
The new species also is morphologically similar to Erogalumna zeucta Grandjean, 1964 from the Neotropical region (see Grandjean 1964Grandjean , 1966) ) in the striate body surface, relatively long prodorsal setae, bothridial setae with small head, well-developed anterior notogastral margin, presence of a postanal porose area and four pairs of notogastral porose areas and the position of setal alveoli la medial to areas Aa.It differs from E. zeucta by the absence of modified leg setae in males (vs.present; this is a generic character of Erogalumna) and the presence of strongly elongated postanal porose area and notogastral porose areas Aa and A3 (vs.Aa slightly elongated, A3 oval).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.