New species of the superfamily Euphthiracaroidea (Acari: Oribatida) from Madagascar and Tanzania

Five new species of the family Euphthiracaridae are described, identified and figured from the Afrotropical region: Oribotritia breviseta sp. nov. from Andasibe National Park of Madagascar; Acrotritia paraardua sp. nov. from Vohimana Experimental Reserve, Ambohitanely Special Reserve and Andasibe National Park of Madagascar; Acrotritia paradikra sp. nov. from Ranomafana National Park and Ankarafantsika National Park of Masagascar; Microtritia diaphoros sp. nov. from the Nguru Mountains of Tanzania; and Microtritia parahauseri sp. nov from the Uluguru Mountains of Tanzania. A comparison with the most closely related species of the genera Oribotritia, Acrotritia and Microtritia is also presented. http://zoobank.org/urn:lsid:zoobank.org:pub:7965FE4C-0AF8-49C4-B894-75D4EFD049BB


Introduction
This study is focused on an investigation of soil ptyctimous mite fauna inhabiting the leaf litter of various types of primeval forests in Madagascar and Eastern Tanzania. Both of these areas are characterized by a high level of plant and animal endemism and are classified as the most important biodiversity hotspots (Myers et al. 2000). Madagascar is one of the largest islands in the world, with very diverse environments and its flora and fauna varying greatly in different parts of the island. Strong endemism of Madagascarian fauna seems to be due to a long isolation of the large island, which has a highly diverse environment. Madagascar was separated from Gondwanaland and the future African continent in the Jurassic period 165 million years ago and subsequently from the Indian subcontinent in the Cretaceous period 80 to 100 million years ago (Goodman and Benstead 2004). The East Usambara mountains including the Nguru Mts and Uluguru Mts are part of the Eastern Arc mountain range of South East Kenya and Eastern Tanzania. Different types of forests in the Eastern Arc are regarded as one of the top biodiversity hotspots in the world on the basis of the high number of endemic plant and animal species including soil invertebrates. This high level of endemism is caused by uninterrupted development of forests continuing for at *Corresponding author. Email: wojciech.niedbala@amu.edu.pl least 30 million years and long-term isolation from the West and Central African forests for at least 10 million years (Burgess et al. 2007;Hall et al. 2009).
Altogether five new species of ptyctimous oribatid mites belonging to three genera Oribotritia Jacot, 1924, from the family Oribotritiidae Grandjean, 1954, Acrotritia Jacot, 1923and Microtritia Märkel, 1964 from the family Euphthiracaridae Jacot, 1930 were found in rich material of soil mites collected by Dr Baňař and Dr Grebennikov from the leaf litter of various forest types in Madagascar and Eastern Tanzania. Their descriptions are the subject of this study (Jacot 1923(Jacot , 1924(Jacot , 1930Grandjean 1954;Märkel 1964).

Material and methods
The leaf litter samples were collected by using a sifting method and were partly extracted by using a Winkler apparatus. All the extracted mite specimens were preserved in 85% ethanol, then mounted and cleared in 80% lactic acid on temporary cavity slides and mounted on temporary slides with glycerol. The determined material was preserved in vials with 80% ethanol. Observations, figures, and measurements were made using a standard light microscope equipped with a drawing attachment. All the measurements are given in micrometres. The terminology is based on that of Niedbała (2000). Type material is partly deposited at the Department of Animal Taxonomy and Ecology, Poznań, Poland (DATE) and partly at the Institute of Soil Biology BC ASCR, České Budějovice, in the Czech Republic (ISB), and partly at the Natural History Museum in Geneva, Switzerland (NHMG).

Description of new species
Oribotritia breviseta sp. nov.
Notogastral setae very short (c 1 /c 1d 1 = 0.2), all needle-like except filiform setae c 3 and p 3 ; oblique arrangement of setae c 1 -3 very strange, setae c 1 situated very far from anterior margin of notogaster, setae c 2 in medium distance and setae c 3 in short distance from notogastral margin. Opening of opisthosomal gland and arrangement of lyrifissures and vestigial setae typical for genus.
Ventral region. Setae h of mentum considerably longer than distance between them. Anogenital cleft trv rather short. Nine pairs of genital and two pairs of short aggenital setae present. Anal plate without setae and three pairs of adanal setae present. Adanal setae ad 3 situated at level between anal setae an 2 and an 3 , anal setae an 1 situated at level between adanal setae ad 1 and ad 2 setae considerably longer than between ad 2 and ad 3 ; lyrifissures iad situated laterally posteriorly of adanal setae ad 2 .

Etymology
The name of the new species 'brevis' is Latin for 'short' and refers to the length of notogastral setae.

Comparison
The new species is easy distinguishable from the related species by the presence of short notogastral setae and the oblique arrangement of notogastral setae c 1 -3.
Notogaster with moderately long notogastral setae stout, covered with small spines in distal half. Setae c 1 shorter than distance between setae c 1 and d 1 , setae c remote from anterior margin of notogaster, setae c 2 more removed than setae c 1 and c 3 . Openings of lateral-opisthosomal gland (gla), lyrifissures and vestigial setae present and positioned typically.
Ventral region. Infracapitulum as for superfamily Euphthiracaroidea. Setae h of mentum longer than their mutual distance. Genitogenital plates with nine pairs of genital setae; all genital setae situated posteriorly of progenital area; two aggenital setae situated slightly obliquely. Anal plates with two pairs of setae. Anodanal plates with three pairs of stout adanal setae; anal setae an 1 and an 2 shorter, smooth, anal setae an 3 minute. Lyrifissures iad situated anteriorly from adanal setae ad 3 .

Etymology
The prefix 'para' is Latin meaning 'near' and refers to the similarity the new species with Acrotritia ardua (C. L. Koch 1841).

Comparison
The new species is similar to A. ardua (C. L. Koch 1841) by the presence of simple, distinct lateral carinae of prodorsum and bidactylous tarsi I and tridactylous tarsi II-IV, but differs by the presence of a clavate head of sensillum (versus fusiform head), the presence of all genital setae outside the progenital area (versus setae g 1 in the progenital position) and by different chaetotaxy of the legs. Another two Acrotritia species have simple lateral carinae of the prodorsum, clavate sensilli and bidactylous tarsi I and tridactylous tarsi II-IV. However, Acrotritia dinota (Niedbała et Schatz, 1996) from Belize and the Galapagos islands has genital setae g 1 situated in a progenital position and Acrotritia munita Niedbała, 2006 from South Africa also has genital setae g 1 situated in a progenital position (Koch 1841;Niedbała and Schatz 1996;Niedbała 2006).

Material examined
Holotype and

Description
Colour yellow, surface of body punctate. Prodorsum with two pairs of distinct lateral carinae; inferior carina long, placed between bothridium and lateral border of prodorsum, superior carina short not parallel, located in anterior part of prodorsum, convergent to middle part of inferior carina. Sensilli fusiform with spinose head. Prodorsal setae with exception of exobothridial (ex) one erect, interlamellar (in) and lamellar (le) setae spinose in distal half, rostral (ro) setae rough. Distance between lamellar (le) setae larger than between rostral (ro) setae.
Notogastral setae rather short, spinose in distal half, their mutual length c 1 < c 1d 1 . Setae c 1 -3 remote from anterior border of notogaster, setae c 3 less than other. Openings of the latero-opisthosomal glands, lyrifissures and vestigial setae present and positioned typically. On the left side in holotype vestigial seta f 1 developed as short, filiform seta.
Ventral region. Setae h of mentum longer than distance between them. Nine pairs of minute genital and two pair of minute aggenital setae present. Three pairs of rough anal and three pairs of adanal setae present. Anal setae an 1 and an 2 shorter than adanal setae, anal setae an 3 minute. Lyrifissures iad located between anal an 3 and adanal setae ad 3 .

Etymology
The prefix 'para' is Latin meaning 'near' and refers to some resemblance to the Neotropical species Acrotritia dikra (Niedbała et Schatz 1996).

Comparison
The new species is similar to Acrotritia dikra Niedbała et Schatz, 1996 in the shape of lateral carinae of prodorsum. These two similar species distinguish by the shape of sensilli, setiform in Acrotritia dikra Niedbała et Schatz, 1996 and fusiform in new species. Some other similar species are distinguishable by the shape of lateral carinae of prodorsum and by monodactylous tarsi (Niedbała and Schatz 1996).
Ventral region. Four pairs of genital setae, no one situated in progenital position, aggenital setae absent. Three pairs of adanal setae present, adanal setae ad 1 the longest. One paratype has one more adanal seta in left side ( Figure 4C). Anal setae an 1 and an 2 shorter than adanal setae, anal setae an 3 vestigial. Lyrifissures iad situated anteriorly of adanal setae ad 3 .

Etymology
The specific name of the new species 'diaphoros' is Greek for 'different' and alludes to a significant difference between the mutual distance of the rostral and lamellar setae of the prodorsum.

Comparison
The new species differs from congeners by the presence of a very small distance between the rostral setae and a very large distance between the lamellar setae. It is similar to the South American species M. schusteri (Märkel 1964) and M. incisa (Märkel 1964) by the presence of a similar shape of sensilli and the presence of four pairs of genital setae. However, the new species is distinguishable by a significant difference between the mutual distance of the rostral and lamellar setae and the presence of well-developed anal setae an 1 and an 2 (Märkel 1964  202, height 217, length of notogastral setae: c 1 53, c 1 /c 1d 1 = 0.6, h 1 and p 1 38; genitoaggenital region 101 × 56, anoadanal region 126 × 45.

Description
Colour yellow. Surface of body punctuated, only posterior part of prodorsum covered with alveoli. Prodorsum with sensilli broadly spindle shaped, smooth. Prodorsal setae fine, short, distance between lamellar (le) setae slightly greater than between rostral (ro) setae; rostral (ro) setae relatively far from distal end of prodorsum; mutual length of prodorsal setae: ro < le > in.
Ventral region with four pairs of genital setae, no one situated in progenital position, aggenital setae absent. Anal setae an 2 and an 3 absent, adanal setae ad 1 and ad 2 the longest. Lyrifissures iad situated anteriorly of adanal setae ad 3 .

Etymology
The prefix 'para' is Latin meaning 'near' and refers to some similarity of the new species with Microtritia hauseri Mahunka, 1993.

Comparison
The new species is distinguishable from congeners by the unusual absence of the anal setae an 2 and an 3 . It is similar to Microtritia hauseri Mahunka, 1993 by the shape of sensilli and the presence of four pairs of genital setae, but is distinguishable by more broad sensilli, a distance between the rostral (ro) setae smaller than between the lamellar (le) setae (versus considerably more in the new species), not one genital setae is situated in a progenital position (versus setae g 1 and g 2 positioned in a progenital position in the new species), genua IV with setae d (versus absence of setae d in the new species) (Mahunka 1993).