New species of Notophthiracarus (Acari: Oribatida: Phthiracaroidea) from Tanzania

Three new species of the genus Notophthiracarus are described, identified and figured from Uluguru Mountains of Tanzania: Notophthiracarus quasiuluguruensis sp. nov, Notophthiracarus tuberculus sp. nov, and Notophthiracarus uluguruensis sp. nov. A comparison with the most closely related species of the genus Notophthiracarus is also presented. http://zoobank.org/urn:lsid:zoobank.org:pub:3FBF24E7-3E2D-4686-AD57-EFEA25510BBD


Introduction
Tropical Africa, south of the Sahara Desert, and especially the area of submontane and montane forests in Tanzania and Kenya, is classified among the most important biodiversity hotspots not only in the Ethiopian region but in the whole world. Part of the Eastern Arc Mountains, the Usambara Mountains are renowned for a high concentration of endemic species and have been identified as one of the world's most threatened forest ecosystems. The area contains moist tropical montane forest above an altitude of 600 m and some of the last remaining but ecologically important lowland montane forest in East Africa (Myers et al. 2000;Brooks et al. 2002;Burgess et al. 2007;Powell et al. 2011).
Mites of the superfamily Phthiracaroidea are an important and abundant component of mesoedafon, especially in forest soils. They are macrophytophages and play an important role in secondary decomposition of organic matter in different types of soil (Luxton 1972;Hågvar 1998). Large material of ptyctimous mites were collected by Dr V. Grebennikov (from Ottawa, Canada) using siftings of various types of leaf litter in many localities in the Usambara Mountains. These samples contained three new species of the genus Notophthiracarus Ramsay, and their descriptions are the subject of this contribution. The superfamily Phthiracaroidea of the Ethiopian region has been reviewed and discussed in detail by Niedbała (2001). In total, 22 species of Phthiracaroidea were summarized from the fauna of Tanzania, comprising 14 endemic species (63.6% of endemism), seven pantropical species and one semicosmopolitan species. Four species belonged to the genus Notophthiracarus and all were endemic.

Material and methods
The soil and 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 used is based on that of Niedbała (2000). Type materials are partly deposited at the Department of Animal Taxonomy and Ecology, Poznań, Poland (DATE), partly at the Institute of Soil Biology BC ASCR, České Budějovice, in the Czech Republic (ISB), and partly at the Natural History Museum, Geneva, Switzerland (NHMG).

Description of new species
Notophthiracarus quasiuluguruensis sp. nov.

Material examined
Holotype

Description
Colour light brown. Surface of body porose and with well-developed sculpture. Prodorsum with well-developed, joined sigillar fields, with deep sinus between rostral setae; lateral carinae absent, posterior furrows feeble. Sensilli long, with pedicel narrow proximally, slightly dilated in the middle part and again narrow with small dilated head covered with minute spines. Setae needleform, rough, except exobothridial setae vestigial.
Notogaster with needleform, short notogastral setae (c 1 /c 1d 1 = 0.5), setae of row c remote from anterior border of notogaster, setae c 2 more than setae c 1 and c 3 . Two pairs of lyrifissures ia and im present. Vestigial setae f 1 and f 2 not observable.
Ventral region, setae h of mentum shorter than distance between them. Formula of genital setae: 5 + 4: 0; genital setae g 1 -4 smaller than setae g 5 -9 . Anoadanal plates with five pairs of unequal in length of setae, ad 2 > an 2 > ad 3 > an 1 > ad 1 , adanal setae ad 1 and ad 2 in unusual position, posteriorly of anal setae. Legs, chaetome of legs of 'incomplete type', setae v′ of femora I absent, setae d of femora I slightly remote from distal ends of the articles.

Etymology
The prefix quasi is Latin meaning 'near' and refers to the similarity of the new species to another new species from Tanzania -Notophthiracarus uluguruensis sp. nov.

Comparison
The new species is very similar to Notophthiracarus uluguruensis sp. nov. in the shape and length of the setae, the joined sigillar fields of the prodorsum and the unusual position of the adanal setae ad 1 and ad 2 . It is distinguishable by porose surface of body (versus surface covered by mosaic), the totally different shape and length of the sensilli, which are long, dilated in the middle with a small head with short spines (versus short, fusiform and rounded), shorter prodorsal setae, absence of lateral carinae of prodorsum (versus presence of carinae), considerably shorter setae h of the mentum than the distance between them (versus h > hh), longer an 2 setae and the absence of v′ setae of the femora I.  Notogaster with strong anterior collar; notogastral setae short, rather smooth, spiniform, dilated proximally and whip-like distally. Setae of row c 1-3 situated at collar. Only lyrifissures im visible; vestigial setae not observable.
Ventral region, setae h of mentum longer than distance between them. Formula of genital setae: 5: 4; genital setae g 1 -4 shorter than setae g 5 -9 ; adanal setae situated closely to paraxial border, near of anal setae, all setae of anoadanal plates short, similar in length, smooth.
Legs, chaetome of legs of 'complete type'. Setae d of femora I slightly remote from distal ends of articles, setae l″ very short.

Etymology
The specific name tuberculus refers to the tubercle-covered surface of notogaster.

Comparison
This species is easily distinguishable from its congeners by the numerous tubercles covering of surface of the notogaster, the powerful prodorsal, median crista and all adanal setae situated near the paraxial border. Slightly similar are Notophthiracarus rafalskii Niedbała, 1997 Niedbała, 2009 from Australia in the shape and length of the setae, the strong crista of the prodorsum and the situation of the setae in the anoadanal plates, but they are easily distinguishable by the absence of an anterior collar and tubercles on the surface of the notogaster (Niedbała 1997(Niedbała , 2006(Niedbała , 2009Niedbała et al. 2006 Notogaster with rather short (c 1 /c 1d 1 = 0.6) rigid, needleform notogastral setae, covered with very short cilia, in shape as prodorsal setae. Setae c 1 and c 2 remote from anterior border of notogaster, setae c 3 near the border. Only lyrifissures ia and im present. Vestigial setae not observable.
Ventral region, setae h of mentum slightly longer than distance between them. Arrangement of genital setae: 6: 3; genital setae g 1 -5 considerably smaller than setae g 6 -9 . Anoadanal plates with unusual arrangement of adanal setae, adanal setae ad 1 and ad 2 situated close to each other both posteriorly of anal setae, adanal setae ad 2 the longest and thickest, all setae rough.
Legs setation of 'complete type'. Seta d on femora I distinctly remote from distal ends of segments.

Etymology
The name of this species uluguruensis alludes to the locality in Uluguru Mountains.

Comparison
The new species is easily distinguishable among the congeners from the joined sigillar fields of the prodorsum and unusual arrangement of the adanal setae ad 1 and ad 2 situated posteriorly of the anal setae.