A preliminary account of the fly fauna in Jabal Shada al-A’la Nature Reserve, Saudi Arabia, with new records and biogeographical remarks (Diptera, Insecta)

Abstract The first list of insects of Al-Baha Province, Kingdom of Saudi Arabia (KSA) was published in 2013 and contained a total of 582 species; an addendum to this list was published in 2015 adding 142 species and bringing the total number recorded from the province to 724 insect species representing 17 orders. The previous two studies excluded Jabal Shada al-A’la Nature Reserve (SANR), so the present study in SANR, as belonging to Al-Baha Province, are complementary to the previous two. The present study presents a preliminary list of Diptera (Insecta) in SANR, with remarks on their zoogeography, and is the first of a series of planned ecological and systematic studies on different insect orders as one of the outputs of a project proposed to study the entire insect fauna of SANR. A total number of 119 Diptera species belonging to 87 genera, 31 tribes, 42 subfamilies, and representing 30 families has been recorded from SANR in the present study. Some species have been identified only to the genus level and listed herein only because this is the first time to record their genera in KSA. Fourteen of the species are recorded for the first time for KSA, namely: Forcipomyia sahariensis Kieffer, 1923 [Ceratopogonidae]; Chaetosciara sp. [Sciaridae]; Neolophonotus sp.1; Neolophonotus sp.2; Promachus sinaiticus Efflatoun, 1934; Saropogon longicornis (Macquart, 1838); Saropogon sp. [Asilidae]; Spogostylum tripunctatum (Pallas in Wiedemann, 1818) [Bombyliidae]; Phycus sp. [Therevidae]; Hemeromyia sp.; Meoneura palaestinensis Hennig, 1937 [Carnidae]; Desmometopa inaurata Lamb, 1914 [Milichiidae]; Stomoxys niger Macquart, 1851 [Muscidae]; and Sarcophaga palestinensis (Lehrer, 1998) [Sarcophagidae]. Zoogeographic affinities of recorded fly species suggest a closer affiliation to the Afrotropical region (46%) than to the Palearctic region (23.5%) or the Oriental region (2.5%). This supports the previous studies’ conclusions and emphasizes the fact that parts of the Arabian Peninsula, including Al-Baha Province, ought to be a part of the Afrotropical Region rather than of the Palaearctic Region or the Eremic Zone.


Introduction
Al-Baha Province (Fig. 1) is situated in the south-western part of the Kingdom of Saudi-Arabia (KSA) between the Holy Makkah and Asir provinces. It is the smallest province in KSA (approximately 10,362 km2), situated at 41-42° E and 19-20° N. It is characterized by natural tree cover (El-Juhany and Aref 2013) and agricultural plateaus. Huge and steep rocky mountains divide the province into two main sectors, a mountainous area known as 'Al-Sarat' or 'Al-Sarah' with an elevation of 1500-2450 m above sea level at the east forming a part of Al-Sarawat Mountains range, and a lowland coastal plain in the west, known as 'Tihama'. The second sector, Tihama, is divided into two districts, Al-Mekhwa and Qelwa (Alahmed et al. 2010, El-Hawagry et al. 2013, 2015. Jabal Shada al-A'la Nature Reserve (SANR) lies between latitudes 19.8149N-19.8763N and longitudes 41.2855E-41.3501E (Fig. 1). It is an isolated granite mountain massif made up of jagged spires and pinnacles, located in Al-Mekhwa district, 20 km to the south-west of Al-Mekhwa city, the capital of the district. It is a dissonant of the Sarawat Escarpment in the foothills of Tihama, measuring 68.62 square kilometers. Its location and its altitudinal range from 490 to 2,222 meters above sea level ensures high rainfall, a wide range of micro-climates, and a high level of biological diversity (SWA 2016).
In the lowland coastal plain, Tihama, the climate is hot in summer, warm in spring and mild in winter, with less than 100 mm of annual rainfall. In the mountainous area, Al-Sarah, the weather is generally cooler due to high altitude, in addition to the formation of clouds and fog accompa nied by thunderstorms in winter, with a rainfall average of 405 mm annually (Ibrahim and Abdoon 2005;. The climate in SANR is intermediate between the climates in these two sectors, with a rainfall average of approximately 200 mm annually (Fig. 2).
SANR, as an isolated mountain massif, supports an exceptionally rich flora; with approximately 500 plant species recorded, including 63 key plant taxa including endemics and Afrotropical relicts, it is the site of highest botanical diversity known in Saudi Arabia. The exceptional floral diversity of SANR, together with the presence of griffon vultures and endemic birds of the southwestern mountains and carnivores such as, the Arabian red fox [Vulpes vulpes arabica Thomas, 1902], Arabian caracal [Caracal caracal schmitzi (Matschie, 1912)], striped hyaena [Hyaena hyaena sultana (Pocock,  Pocock, 1934], sand cat [Felis margarita harrisoni Hemmer, Grubb & Groves, 1976], and reportedly the Arabian leopard [Panthera pardus nimr Hemprich & Ehrenberg, 1833], makes this small protected area a unique  . In Jabal Shada al-A'la Nature Reserve (Worldclim database: http://www.worldclim.org/). treasure of biological diversity. Small communities on the mountain grow a distinctive variety of coffee and other crops in terraced fields (El-Hawagry et al. 2013;SWA 2016;UAEinteract 2016).

1934)], Arabian wolf [Canis lupus arabs
The purpose of this paper is to present a preliminary list of Diptera (Insecta) in SANR, Al-Baha Province, KSA, with remarks on their zoogeography. This is not the final list of Diptera that occur at SANR with the study serving as a basis for further investigations as many additional collected species are still unidentified and further studies are planned to be carried out at SANR. Also, this is the first of a series of planned ecological and systematic studies on different insect orders as one of the outputs of a project proposed to study the entire insect fauna of SANR. El-Hawagry et al. (2013, 2015 studied the insect fauna of Al-Baha Province excluding SANR, so the present study and other future studies in SANR are complementary to the previous two studies. Studies on the fauna of SANR are of particular interest as this area lies in a part of the Arabian Peninsula which is thought by many authors to touch three of the main zoogeographical regions: the Palaearctic, the Afrotropical, and the Oriental (Hölzel 1998).
The Afrotropical Region is supposed to encompass all of Africa south of the Sahara, with the island of Madagascar and the nearby smaller islands. Many authors add parts of the Arabian Peninsula to the Afrotropical Region as well, but there seems to be no agreement as to how much . This may be deduced from the fact that the south-western and southern parts of the Arabian Peninsula including Al-Baha Province are strongly influenced by a subtropical to tropical climate with spring and summer rains (Abdullah and Al-Masroui 1998), and are thus dominated by a xeromesic tropical flora of palaeotropical origin, that in fact represents the impoverished northern part of an African flora (Ghazanfar and Fisher 1998;Hegazy et al. 1998 (Ghazanfar and Fisher 1998;Zohary 1973;Thomas 2016). Sclater (1858) and Wallace (1876) proposed the classical zoogeographical regions and placed the northern border of the Afrotropics along the Tropic of Cancer, i.e. the northern limit of the Afrotropical Region was placed in Taif area, some 200 km north of Al-Baha Province (Hölzel 1998). Crosskey (1980) considered the northern boundaries of Yemen as the regional boundary between the Afrotropical and Palaearctic parts in the Arabian Peninsula. Extensive sampling of Insects in the Arabian Peninsula by many authors in Yemen, Oman, the United Arab Emirates and south-western mountains of KSA, have raised some interesting questions about the true extent of the Afrotropical Region in this important transitional zone. Authors indicate that Wallace's (1876) concept of the extent of the Afrotropical Arabian Peninsula is more accurate than Crosskey's (1980) limited concept of Yemen alone (Kirk-Spriggs andMcGregor 2009, El-Hawagry et al. 2015). However, Uvarov (1938), Greathead (1980) and Larsen (1984) agreed that the south-western part of KSA including the study area should be united with the central Arabian deserts which are either considered as a part of the Palaearctic or by some authors as an autonomous Eremic Zone (also called the Saharo-Sindian faunal region).

Material and methods
Flies were collected from different localities in SANR over two successive years, 2014 and 2015 by the authors. Twelve collecting trips were made, six in 2014 in February, April, June, August, October and December, and six in 2015 in January, March, May, July, September and November. Collections were made in 6 different localities representing different altitudinal levels and habitats in SANR (Figs 13-18, Table 1). The collecting methods included sweep and aerial nets (randomly), bait traps (irregularly), light traps (6 traps, one in each locality, for one night in each trip), Malaise traps (6 traps, one in each locality, for one day in each trip), pitfall traps (90 traps, 15 in each locality, for three days in each trip), and vacuuming (one time in each locality, for 15 minutes in each trip). In addition, a few specimens were incidentally collected by hand.
All taxa are identified and arranged in alphabetical order. Dates of collection for each species are included for the purpose of mapping the activity periods of species in the study area. Each collection date is followed, between parentheses, by the method of collection used, and the latter is followed by the locality number from which the specimens are collected.
Zoogeographical affiliations of species reported in the study area were estimated using world catalogues and counted to calculate the percentage of Afrotropical, Palaearctic or Oriental elements.
Unidentified specimens (or photos of specimens)were sent to experts for identification, as indicated after each of these taxa in the list.
Flies of suborder Nematocera were examined and preserved in alcohol, while other flies were glued to pinned stiff paper points, and all are deposited at the King Saud University Museum of Arthropods, Riyadh, Saudi Arabia (KSMA).
Abbreviations used:

Results
A total of 119 fly species belonging to 87 genera, 31 tribes, 42 subfamilies, and representing 30 families was recorded from SANR through the present study. Some species have been identified only to genus and listed herein as the genera were not previously recorded from KSA.

Discussion
In terms of vegetation and speciation, the south-western part of KSA, including Al-Baha Province, is considered to be the most important part of the country and the Arabian Peninsula in general. Floristically and ecologically, this area is similar to the high altitude mountains of north-eastern and eastern parts of Africa, and like other areas in the south-western part of the Arabian Peninsula, contains montane woodlands and evergreen shrub lands, with strong Afromontane affinities (Bussmann and Beck 1995;Zohary 1973;Eig 1938).
Considering the insect fauna as a whole, El-Hawagry et al. (2013, 2015 attributed the extraordinary complex and the interesting insect fauna in Al-Baha Province to its geographical position at the junction of two of the world's main zoogeographical regions, the Afrotropical and the Palaearctic. Many present day biogeographers think that the biogeographical divisions within the eastern and the northeastern parts of Africa should be extended towards east within the Arabian Peninsula as well, covering the high altitude regions of the southern Al-Sarawat Mountains, namely "Afromontane Archipelago" (Zohary 1973;Eig 1938). Bolton (1994), Eig (1938), El-Hawagry et al. (2013 and2015) and Sharaf et al. (2012aSharaf et al. ( , 2012b concluded that the insect faunal composition in Al-Baha Province has an Afrotropical flavor as the Afrotropical elements were predominantly indicated, they tended to agree with those biogeographers who think that parts of the Arabian Peninsula, including Al-Baha Province, should be included in the Afrotropical region, but they couldn't indicate the northern border of this region exactly. All these facts seem to be reflected somehow on the fly faunal composition in Jabal Shada al-A'la Nature Reserve (SANR) as shown in the present results which obviously emphasize the fact that Al-Baha Province, as lying in the south-western part of the Arabian Peninsula, should be included in the Afrotropical Region rather than in the Palaearctic Region or the Eremic Zone.

Funding
The authors would like to extend their sincere appreciation to the Deanship of Scientific Research at King Saud University for its funding this research group NO (RGP-1437-009).
bert, School of Life Sciences, University of Nottingham, UK; and Mr Ahmed Shams Al Ola, Plant Protection Department, College of Food and Agriculture Sciences, King Saud University, Saudi Arabia. Sincere thanks go to the research team of the KSMA for collecting and mounting specimens.