Checklist of the water mites ( Acari , Hydrachnidia ) of Iran : Second supplement and description of one new species

As a supplement to the list of the mite fauna of Iran compiled by Pešić and Saboori (2007), an additional faunistic list of water mites (Acari, Hydrachnidia) from Iran is presented based on recently published data. The total number of species and subspecies of water mites (Acari, Hydrachnidia) recorded from Iran up to date is 186 species, in 43 genera and 25 families. Based on new material, one new species, Atractides elburzensis n. sp. is described from a stream in N Iran.


Introduction
The cheklist of water mites of Iran published by Pešić and Saboori (2007) included 145 species, in 38 genera and 25 families of water mites.The recent publication of 41 taxa from Iran resulted in a new list which is aimed by the present supplement.Sepasgosarian (1999) and Pešić and Saboori (2007), respectively, summarized the research on the water mites fauna until that time and mentioned that this fauna is not well known.However, both authors pointed that a rich fauna of water mites could be expected.To date, two check lists of water mites of Iran have been published (Sepasgosarian 1999, Pešić andSaboori 2007).Publication of this supplement aims to update the checklist of water mite fauna of Iran, in order to facilitate access to all published data and helps future research activities by understanding major gaps in our knowledge of the water mite fauna of Iran.

Material and Methods
Using publications and original data from 2007 onwards, a checklist was compiled of the water mite fauna of Iran.Postgraduate theses and scientific meetings are no formal publications and are consequently not included in this paper.
For each species, the Iranian provinces (Fig. 1) are listed where the species has been collected.The names of the species are in accordance with the most recent literature (e.g., Davids 2007, Di Sabatino et al. 2010).For new records, water mite were collected by hand netting, sorted on the spot from the living material, conserved in Koenike's fluid and dissected as described elsewhere (e.g., Gerecke et al. 2007).

Research Article
Holotype of new species is deposited in the Museum of Natural History of Montenegro in Podgorica (MNHP).
All measurements are given in µm.For a detailed description and discussion of the characteristics of the genus Atractides and a detailed methodological introduction, see Gerecke (2003).

Discussion
At the present state of knowledge, the number of species and subspecies of water mites recorded from Iran tallies 186 species, in 43 genera and 25 families.As stated already by Pešić and Saboori (2007), this number is far from a reliable estimation of the number of water mite species in Iran.This number is lower than number of water mites in some neighbouring areas, such as Turkey or the Balkan Peninsula, or even lower than number of water mites in some European countries which are much smaller compared with Iran (see Fig. 4).Pešić and Saboori (2007) stated that "further studies to improve our knowledge on Iranian water mites should focus on collecting in little known areas, a revision of the still unstudied material from additional families (such as Lebertiidae) and filling the large gaps in our knowledge regarding the diversity of water mites in stagnant waters and in hyporheic habitats".From 2007 an attempt was made for sampling in the area where water mites have never been sampled (e.g., Persian sea drainage basin), but standing waters and hyporheic habitats have received little attention thus far.Further, some families such as Lebertiidae are still insufficiently studied.
The distribution of research on water mite fauna in Iran is uneven (Table 1).Only from one province more than 50 species is known.Seven provinces have species numbers between 20 and 50, from the remaining provinces less than 20 species are known.Additional field work is highly needed for an appropriate evaluation of the extant water mite biodiversity in Iran.The publication of this checklist should help to stimulate further studies on this important but still not well studied group of invertebrates.

Table 1 .
Number of water mite species per Iranian province.From 2004 divided into 3 provinces (North Khorasan, South Khorasan and Razavi Khorasan)