Contribution to the knowledge of the oribatid mite genus Kalloia (Acari, Oribatida, Carabodidae), with description of a new species from Indonesia

The genus Kalloia (Oribatida, Carabodidae) is recorded in the Oriental region for the first time. A new species — Kalloia gerdweigmanni n. sp. — is described from litter of oil palm plantations and jungle rubber agroforests from Sumatra, Indonesia. It differs from Kalloia simplisetaMahunka, 1985 by the presence of a transverse ridge in the mediodistal part of the lamellae, translamella and two thick, diagonal, convergent ridges forming a triangular structure in the medioanterior part of the notogaster, and by the localization of notogastral setae da, dm, la, lm, lp and h1. The generic status of Kalloia is discussed and supported. Kalloia mahunkai Pérez-Íñigo and Baggio, 1989 and Machadocepheus foveolatusMahunka, 1978, which were considered representatives of Kalloia, are removed from this genus and combined preliminarily in Gibbicepheus. Revised generic diagnosis and data on ecology and distribution of known species of Kalloia are presented.

In the course of the study of carabodid mites from Indonesia, we found a new species of Kalloia. This paper aims to describe and illustrate this new species under the name K. gerdweigmanni n. sp., to update the generic diagnosis, to discuss the taxonomic status of Kalloia and the systematic placement of K. mahunkai and M. foveolatus (to include both species in Gibbicepheus), and to present data on the ecology and distribution of Kalloia species.

Material
This study was carried out within the framework of the interdisciplinary project "Ecological and socioeconomic functions of tropical lowland rainforest transformation systems (Sumatra, Indonesia)" -EFForTS on Sumatra Island (http://www.uni-goettingen.de/en/310995.html). See the Material examined section for detailed location data of the new species.
In order to study the morphology of the genus Kalloia, besides the new species, the specimens of Kalloia simpliseta from S.G. Ermilov's collection, from Cuba (Ermilov 2016) and the Caribbean (Ermilov and Smit 2017), were used.

Methods
Specimens were mounted in lactic acid on temporary cavity slides for measurement and illustration of the new species. Body length was measured in lateral view, from the tip of the rostrum to the posterior edge of the notogaster. Notogastral width refers to the maximum width of notogaster in dorsal view. Lengths of body setae were measured in lateral aspect. All body measurements are presented in micrometer. Formulas for leg setation are given in parentheses according to the sequence trochanter-femur-genu-tibia-tarsus (famulus included). Formulas for leg solenidia are given in square brackets according to the sequence genu-tibia-tarsus.
Drawings were made with a camera lucida using a Leica transmission light microscope "Leica DM 2500". SEM photos were made with the aid of a FEI Quanta 250 SEM microscope.
The general morphological terminology used in this paper mostly follows that of F. Grandjean: see Travé and Vachon (1975) for references, Norton (1977) for leg setal nomenclature, and Norton and Behan-Pelletier (2009) for overview.
Juvenile instars -Not known.
Notogaster (Figs 1a, 1b, 2a, 4a, 4b, 5b, 5c, 5a) -Anterior notogastral margin straight. Anterior and posterior notogastral depressions and dorsocentral hump-like process welldeveloped. Medioanterior region of notogastral hump-like process with two thick, diagonal, convergent ridges, forming triangular structure directed in anterior notogastral depression. Medioposterior region of notogastral hump-like process with one pair of tubercles, located behind diagonal ridges; these ridges and tubercles fused or indistinctly connected. Posterolateral regions of notogastral hump-like process with one pair of large, elongate tubercles. Fifteen pairs of notogastral setae (32-36) setiform, thin, slightly barbed; of these, da and dm located on diagonal notogastral ridges; dp on medioposterior tubercles; la, lm, lp and h 1 on posterolateral tubercles. Lyrifissures and opisthonotal gland openings well visible; ia located on humeral shoulders, im and gla close to each other and anterolateral to posterolateral tubercles, ip between p 1 and p 2 , ips and ih on lateral sides of notogaster.
Anogenital region (Figs 1b, 2a, 5b, 6b, 5c) -With one pair of long, longitudinal ridges lateral to genital aperture and posterior to epimere IV and several anogenital depressions (one large depression between genital and anal apertures; one pair of small depressions close and posterolateral to genital aperture; one pair of small depressions bearing aggenital setae; one pair of large and indistinct depressions lateral to anal aperture; two pairs of medium depressions posterior to acetabula IV). Usually with three poorly visible short, thin, parallel diagonal furrows lateral to genital aperture. Four pairs of genital, one pair of aggenital and three pairs of adanal setae similar in length (32-36), setiform, slightly barbed. Two pairs of anal setae (8) spiniform. Adanal lyrifissures removed from anal aperture and located lateral to ad 3 . Circumventral ridge poorly developed, interrupted posteriorly.
Material examined -Holotype (female) and two paratypes (two females): Indonesia, Sumatra, Bukit Duabelas landscape, oil palm plantation, research site BO3a, 02°04'15.2"S, Type deposition -The holotype is deposited in the collection of LIPI (Indonesian Institute of Science) Cibinong, Indonesia; one paratype is deposited in the collection of the Senckenberg Museum of Natural History, Görlitz, Germany; three paratypes are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia. All in ethanol with a drop of glycerol. Additional pictures are available in the online repository www.ecotaxonomy.org.
Etymology -The species name is dedicated to our colleague, the well-known acarologist Prof. Dr. Gerd Weigmann (Free University of Berlin, Institute of Zoology, Berlin, Germany), for his extensive contributions to our knowledge of oribatid mites.
Remarks -Kalloia gerdweigmanni n. sp. differs from the type species of the genus -Kalloia simpliseta Mahunka, 1985 -by the presence of a transverse ridge in the mediodistal part of lamellae (versus ridge on lamellae absent), translamella (versus translamella absent) and two thick, diagonal, convergent ridges, forming a triangular structure in the medioanterior part of the notogaster (versus notogastral ridges absent), and the localization of each pair of notogastral setae da and dm on one ridge (versus setae located on separate tubercles) and la, lm, lp and h 1 on one large elongate tubercle (versus la and lm on one small tubercle; lp and h 1 on another small tubercle). Mahunka (1985) proposed the monotypic genus Kalloia with Kalloia simpliseta from the Caribbean. Later, he confirmed the generic status (e.g., Mahunka 1986Mahunka , 1998, and this was also supported by other authors (Balogh and Balogh 1988, 1992, 2002Fujikawa 1991;Ermilov 2016;Ermilov and Smit 2017;Ermilov and N'Dri 2018). Subías (2004) included

Leg Tr
Fe Note: Roman letters refer to normal setae, Greek letters to solenidia (except ɛ = famulus). Single prime (' ) marks setae on anterior and double prime (" ) setae on posterior side of the given leg segment. Parentheses refer to a pair of setae.
Kalloia as subgenus in Diplobodes Aoki, 1958 andlater (2016) in Gibbicepheus;  included it in Machadocepheus (Kalloia) Balogh, 1958. The genus Kalloia is morphologically similar to Diplobodes, Gibbicepheus and Machadocepheus, however it differs from Diplobodes and Gibbicepheus by the distinctly depressed anterior part of the notogaster and by the presence of a centrodorsal notogastral hump-like process (versus anterior part of notogaster not depressed; centrodorsal part of notogaster without hump-like process); and from Machadocepheus by the absence of a centrodorsal prodorsal hump-like processes on which the interlamellar setae are located. Also, the genus Kalloia is morphologically similar to the genera Tuberocepheus Balogh and Mahunka, 1969 andMangabebodes Fernández, Theron, Leiva, Rollard andTiedt, 2014 in having especially a centrodorsal notogastral hump-like process and distinctly depressed anterior and posterior parts of the notogaster. However, it differs from both by the presence of 15 pairs of notogastral setae, including the presence of notogastral setae c 1 -c 3 and their localization in the depressed anterior part of the notogaster (versus 12 pairs of notogastral setae, setae c 1 -c 3 absent, depressed anterior part of the notogaster without setae).
According to recent studies of Carabodidae, the presence or absence of prodorsal and notogastral depressions and hump-like processes and localization of interlamellar and notogastral setae are important morphological traits on generic level (Fernandez et al. 2013(Fernandez et al. , 2016(Fernandez et al. , 2018Ermilov 2018;Ermilov and Starý 2018), therefore we support the generic status of Kalloia.
Pérez-Íñigo and Baggio (1989) described the second representative of Kalloia, Kalloia mahunkai from Brazil. In addition, Subías (2004) included the species Machadocepheus foveolatus from Mauritius in Diplobodes (Kalloia) and later (2016) in Gibbicepheus (Kalloia), implying that this species is the third representative of Kalloia. However, K. mahunkai and M. foveolatus do not have anterior notogastral depression and no centrodorsal notogastral hump-like process (generic traits of Kalloia) and correspond to generic traits of the genus Gibbicepheus, therefore we suggest to exclude these two species from the genus Kalloia, and to combine them in Gibbicepheus.
Kalloia simpliseta is widely distributed in the Caribbean. It was described from several localities in Saint Lucia (Mahunka 1985): litter with underlying soil from a natural forest in Micoud, Mahaut, Quilesse Reserve; under bark of coastal trees, accumulated rotten material at tree bases in Anse La Raye, Pilori Pt.; sifted litter, wooden debris from various forest sites in Vigie. Later, the species was recorded by Mahunka (1998) in Saint Lucia from forests in the vicinity of Halcyon Sands Hotel in Vigie, and by Ermilov and Smit (2017) from litter and soil from different Caribbean islands (Antigua, Grenada, Saint-Barthelémy, Trinidad).
Kalloia gerdweigmanni n. sp. is recorded from litter of oil palm plantations and jungle rubber agroforests in Bukit Duabelas and Harapan landscapes, Sumatra, Indonesia.