Erythraeid mites (Prostigmata, Erythraeidae) from Saudi Arabia, description of three new species and a new record

Abstract Three erythraeid genera Balaustium von Heyden, Charletonia Oudemans, and Erythraeus Latreille (Trombidiformes: Prostigmata) are reported for first time from Saudi Arabia based on three new larval species, Balaustium yousifi sp. n., Charletonia bahaensis sp. n., and Erythraeus (Erythraeus) uhadi sp. n. and one new record Erythraeus (Zaracarus) lancifer Southcott. All the three new species are described and illustrated from larvae.

The genus Charletonia Oudemans comprises 117 species: two species described from both larvae and post larval stages; 92 species described only from larvae, and 23 species known only from post larval stages (Haitlinger 2007, Beron 2008Wohltmann 2012, 2013). Most larval species of this genus were recorded as parasites on Orthoptera and Heteroptera (Haitlinger 2004a;Mayoral and Barranco 2011;Saboori et al. 2012;Haitlinger et al. 2014), however some larval species were recorded free living on herbaceous plants (Haitlinger 2004a, b;Hakimitabar and Saboori 2011). The free living larvae might be collected at early larval period while searching different hosts on herbaceous plants.
The genus Balaustium von Heyden widespread in the world, comprises 36 nominal species: 5 species described from both larval and post-larval stages, 17 described only from post larval stages, and 14 species based only on larvae Mąkol and Wohltmann 2012). Larvae of Balaustium were generally collected from plants (Mayoral and Barranco 2009;. Only B. wratislaviensis Haitlinger, 1996 was collected from different vertebrates species (Passeriformes: Paridae) (Haitlinger 1996). Family Erythraeidae is very poorly known in Saudi Arabia. Previously only Leptus tammuzi Haitlinger, 1994 was reported from this country (Haitlinger 1994). In this study, three genera, Balaustium, Charletonia and Erythraeus are reported for the first time from Saudi Arabia with three new species viz. B. yousifi sp. n., C. bahaensis sp. n. and E. (E.) uhadi sp. n. and one new record E. (Z.) lancifer Southcott.

Materials and methods
Three regions of Saudi Arabia, Al-Riyadh, Al-Madina and Baha, were surveyed for the collection of erythraeid mites during the years 2012-2013. Two collection methods were used: i) different plant parts were shaken over pieces of white paper and the mites were transferred using camel hair brush into 70% alcohol; ii) Tullgren funnels were used to extract mites from plant material brought to the laboratory. Mites parasitic on different insects were collected and preserved along with their hosts. Later, the mites were detached from their hosts under the stereomicroscope (Olympus®, SZX10, Japan). The collected mite specimens were cleared in Nesbitt's fluid for 10-12 h. Subsequently, the specimens were mounted on slides in Hoyer's medium, and dried in oven at 40 °C for one week. The mounted specimens were examined under a phase-contrast microscope (DM2500, Leica®, Germany). Template illustrations were either drawn with pencil by using a drawing tube (Olympus®, Japan) attached to the microscope, or different body parts of mites were pictured with an Auto-montage Software System (SYNCROSCOPY®, Cambridge, UK) attached to the microscope. Final processing of drawings was done in Adobe Illustrator (Adobe Systems Incorporated, USA). The terminology used in this study follows that of Haitlinger and Saboori (1996). All measurements are given in micrometers. The measurements in description refer to the holotype followed by as a range of paratypes in parenthesis. Description. (Holotype larva): Dorsum: Prodorsal scutum with two pairs of sensilla (ASE and PSE) and two pairs of setae (AL and PL). AL located slightly anterior to ASE bases, PSE present at posterior pole of scutum, Posterior pair of sensilla (PSE) more than three times longer than anterior pair ASE, both finely ciliated on their distal halves. Cuticular lines surround both sensilla. AL longer than PL, both with long dense barbs on their entire lengths. Prodorsal scutum almost pentagonal in shape, straight anteriorly, round posteriorly, widest at the level of PL setae (Fig 3). Two pairs of eyes present at the level of posterior end of scutum dorsolaterally on idiosoma, anterior pair 24 (22-24) across, posterior pair 14 (13-14) across. Dorsal setae on idiosoma, 16 pairs (fD = 32), barbed and ranging in lengths from 29-61 (28-64) (Fig. 1).
Etymology. The specific epithet is derived from the name of famous mountain "Uhad", where holotype larva was collected.
Legs: Legs seven segmented with divided femora, all longer than body length. Tarsi I-III terminate in two lateral claws and claw like empodium.
Etymology. The specific epithet is derived from the city name "Baha" (in Saudi Arabia) where it was collected.