New mite records (Acari: Mesostigmata, Trombidiformes) from soil and vegetation of some Syrian citrus agrosystems

This study gives the result of collections of mite fauna inhabiting soil, litter and plant species surrounding citrus orchards at three localities in Latakia governorate. Mites collected were identified and only new recorded species are presented. During this study, 21 species belonging to 12 families (4 Mesostigmata and 8 Trombidiformes) were reported as new to the Syrian fauna. Five species were phytophagous mites (belong to Tenuipalpidae and Tetranychidae), while the others are considered as generalist predators or feed on microorganisms in their habitats. The results could be of importance for integrated pest management applied in Syrian citrus orchards.


Introduction
Latakia is the main growing citrus governorate in Syria, produced about 0.90 million tons of citrus fruit in 2016 (Syrian Ministry of Agriculture and Agrarian Reform, 2016). In this governorate, recent surveys conducted in about 60 citrus orchards revealed the presence of 60 mite species belonging to 20 families. Of these, 22 mite species belonging to 11 families inhabit citrus leaves (nine Phytoseiidae, three Tetranychidae, two Cheyletidae, and one of each Acaridae, Camerobiidae, Cunaxidae, Iolinidae, Raphignathidae, Stigmaeidae, Tenuipalpidae and Tydeidae). Remaining taxa were collected from litter and (or) from vegetation adjacent to those orchards (Zriki et al., 2015;Barbar, 2016Barbar, , 2017Barbar and Ueckermann, 2017;. These results showed the presence of a relatively high number of mite species, especially predators of phytophagous mites and other micro arthropods (Barbar, 2016). However, more investigations are needed to obtain a good vision about the diversity of this fauna in Latakian citrus agro ecosystems. The results of these investigations could be of a great interest to further studies about the use of predatory mites in the biological control programs.
The aim of the present study was to identify mite species inhabiting soil, litter and plant species surrounding citrus orchards at three localities in Latakia governorate, and to provide data (when available) about their trophic habits, geographic distribution and economic importance.

Materials and methods
Surveys of mite fauna were conducted in Latakia governorate in April and May, 2016, March and April, 2017, and March, 2018. Mite collected from: (1) leaves of common plant species surrounding citrus orchards located at Burj-Islam (35°40'12" N, 35°7'24" E) and Attabiyyat (35°30'24" N, 35°46'49" E); (2) ground litter of a pesticides free citrus orchard located at 35°48'33" E). Mites were removed from leaves using the "dipping-checking-washing-filtering" method (Boller, 1984). For collecting mites from litter, materials were placed on a sieve (25 cm Ø x 10 cm; its screen with 5 mesh/cm) and shaken over a black plastic sheet (1.5 m 2 ). Mites were picked off the sheet into a vial with 70 % alcohol. Mites were then mounted on slides in Hoyer's medium and dried in an oven at 40°C for four days.
All mite species that have already been recorded from Syria were excluded from results.

Family Laelapidae
This is the first record of this family from Syria. Two species were collected:

Androlaelaps aegypticus Hafez, El-Badry and Nasr, 1982
Specimen collected -Al-ya'robiyah: One female from litter and soil under Eucalyptus sp., 30 March, 2017. This is the third international record of this species. It was previously recorded from Egypt (Hafez et al., 1982) and Iran (Soleimani et al., 2010). Androlaelaps aegypticus is a very active predator and can feed on immature stages of Tyrophagus putrescentiae (Schrank), Rhizoglyphus echinopus (Fumouze and Robin) (Acaridae) and Lepidoglyphus destructor (Schrank) (Glycyphagidae). Differences in biological characteristics (incubation period, life cycle and female fecundity) of this species were observed according to prey and temperatures (Mostafa et al., 2017).

Family Phytoseiidae
This is the largest known family from Syria with 23 reported species (Barbar, 2017;Demite et al., 2018). One additional phytoseiid species is recorded in the present study: Typhlodromus (Typhlodromus) ernesti Ragusa and Swirski, 1978 Specimens collected -Borj-Islam: Nineteen females and two males on Pinus halepensis Mill., 25 May, 2016. It was associated with the tenuipalpid species Cenopalpus wainsteini (Livschitz and Mitrofanov) in this study. This species is known from several countries in Europe and also from Tunisia but nothing is known about its biology (Demite et al., 2018).

Order Trombidiformes Family Anystidae
This is the first record of this family from Syria. Two species were collected: Anystis wallacei Otto, 1992 Specimens collected -Al-ya'robiyah: One tritonymph and one deutonymph from litter under Acacia cyanophylla Lindley, 21 and 30 March, 2017, respectively. This species is described from pastures in France, Spain, Morocco and Australia and could be a natural enemy of penthaleid mite species and Collembola (Otto, 1992;Gerson et al., 2003).
Erythracarus pyrrholeucus (Hermann, 1804) Specimens collected -Al-ya'robiyah: Four females from litter and soil under A. cyanophylla, 28 and 30 March, 2017. This species is recorded from Australia, Iran, Ukraine and the United States (Otto 1999). Small mite species and insects (i.e., Psocoptera) appear to be a possible food-source for species of Erythracarus including E. pyrrholeucus (Otto, 1999).

Family Cryptognathidae
This is the first record of this family from Syria. One species was collected: Favgognathus cordylus Luxton, 1993 Specimens collected -Al-ya'robiyah: One female from litter and soil under A. cyanophylla, 7 April, 2017. Nothing is known about the biology of this species. However, members of this family probably feed on the content of plant cells or on microorganisms in their habitats (Luxton, 1993;Swift and Goff, 2001).

Family Eupalopsellidae
This is the first record of this family from Syria. One species was collected: Eupalopsis maseriensis (Canestrini and Fanzago, 1876) Specimen collected -Borj-Islam: One female on unidentified plant species, 25 May, 2016. This species preys on the citrus chaff scale Parloria pergandii Comstock. It was recorded from wild plant species and litter in several countries (i.e., Italy, USSR and Turkey) (Doğan, 2008;Meyer and Ueckermann, 1984).

Family Raphignathidae
Only one species of this family is known from Syria (i.e., Raphignathus gracilis (Rack); Barbar, 2016). Two additional species were collected in this study:

Family Stigmaeidae
Only one species of this family is known from Syria (i.e., Agistemus exsertus Gonzalez-Rodriguez; Barbar, 2016). Four additional species were collected in this study:

Stigmaeus additicius Dönel and Doğan, 2011
Specimen collected -Al-ya'robiyah: One female from litter and soil under A. cyanophylla, 7 April, 2017. This is the second international record of this predatory mite. It was described from Turkey from litter under Acacia sp. and from moss and lichen on soil (Dönel and Doğan, 2011).

Stigmaeus ayyildizi Dönel and Doğan, 2011
Specimens collected -Al-ya'robiyah: Three females from litter and soil under A. cyanophylla, 7 April, 2017. This is the second international record of this mite species. It was described from Turkey from grassy soil (Dönel and Doğan, 2011).

Family Tenuipalpidae
Five species of this family are known from Syria (Barbar, 2016). Three additional species were collected in this study: Brevipalpus oleae Baker, 1949 Specimens collected -Borj-Islam: Two females on O. europaea, 25 May, 2016. This species was associated with the phytoseiid, Typhlodromus (Typhlodromus) athiasae Porath and Swirski in this study. It was recorded from Morocco, Greece, Italy, Portugal and Tunisia (Castagnoli and Pegazzano, 1986;Chatti et al., 2017).
( T.) athiasae in this study. It was described from France on Viburnum tinus L. and found also on other plant species in several countries (Mesa et al., 2009).

Family Tetranychidae
Fifteen species of this family are known from Syria (Migeon andDorkeld, 2006-2017;Zeity, 2017). Two additional species were collected in this study:

Bryobia kissophila Eyndhoven, 1955
Specimens collected -Al-ya'robiyah: Six females and one larva on Malva sylvestris L., 16 April, 2016. This species was collected from three plant species particularly from Hedera helix L. in Europe and was also collected from other countries as South Africa, Australia and United States (Migeon andDorkeld, 2006-2017). This species was also previously recorded on S. spinosum in Ukraine (Livshits and Mitrofanov, 1969) and Italy (Vacante, 1983) and on Silene dioica (L.) (unknown locality, Migeon andDorkeld, 2006-2017). The Syrian specimens are very close to those described by Figure 1 Variations in the shape of dorsal body setae in the Syrian specimens of Pseudobryobia nikitensis: a -prodorsal setae; b -sc1 seta; c -c1 seta; d -d1 seta. Livshits and Mitrofanov (1969) and similar to those reported in the redescription of Vacante (1983), except for a few small morphological differences namely: (1) in Syrian specimens, setae v1-v2 elongated, slender and serrate ( Figure 1a); setae sc1-sc2 and c1-c3 subspatulate (Figure 1b, c); remaining dorsal body setae palmate serrate and almost rounded distally ( Figure  1d), but dorsohysterosomal setae are subspatulate, lanceolate and more or less acute in the description of Livshits and Mitrofanov (1969), and setae d, e, and f are subspatulate in the redescription of Vacante (1983) (according to Figure presented); (2) femur II with 9 (10) setae in Syrian specimens oppose to 8 in the description of Livshits and Mitrofanov (1969); genu III with 6 (7) setae in Syrian specimens oppose to 5 setae in the description of Livshits and Mitrofanov (1969).
Furthermore, the assignment of this species to the genus Pseudobryobia may be uncertain. Indeed, in the diagnoses proposed by the authors who worked on this genus (e.g. Meyer, 1987;Baker and Tuttle, 1994;Smiley and Baker, 1995), in addition to the absence of prodorsal lobes, it is mentioned that members of the fourth pair of dorsocentral setae (f1 setae) are located in normal dorsal position (not marginal). However, this condition is neither met by the specimens of P. nikitensis described by Livshits and Mitrofanov (1969), Vacante (1983) nor by those reported in this study.