First record of the medically significant scorpion Leiurus abdullahbayrami (Scorpiones: Buthidae) for Lebanon

Abstract. The first record of Leiurus abdullahbayrami Yağmur, Koç & Kunt, 2009 for Lebanon is presented, collected in the East Bekaa province. This is the second Leiurus species reported for this country. The medical importance of L. abdullahbayrami, associated with severe and fatal cases among children in Turkey and Syria, makes it highly relevant to determine its current distribution range in the Levant region.

width ratio is 4.43 in the female specimen and 4.31 in the male specimen, whereas this ratio is 5.42 in males and 5.64 in females of Leiurus hebraeus. These ratios are slightly lower than those reported by Yağmur et al. (2009). Leg I-IV with short spines on the ventral side of the tarsus. Basitarsus of legs I-III with bristlecombs, basitarsus of legs IV without bristlecombs. Pectinal tooth number is 30-30 in the female specimen and 36-37 in the male specimen (Fig. 3). Distribution. Syria (Khalil & Yağmur 2010), Turkey (Yağmur et al. 2009) and Lebanon (present study). Yağmur et al. (2009) reported three colour variations of Leiurus abdullahbayrami in Turkey. In addition, Khalil & Yağmur (2010) reported a population of L. abdullahbayrami from Homs (Syria), about 70 km from the Lebanese border, in which the specimens have the same colour pattern as in Gaziantep (Turkey), i.e. brown. However, the specimens from Bekaa in Lebanon are black, similar to those from the Hatay (Turkey) (linear distance of about 240 km). Interestingly, the population from Homs comprising brown L. abdullahbayrami is located much closer (about 80 km north of collection sites in Bekaa). The third colour variation comprises grey specimens, which are found in the region east of the Euphrates River.

Discussion
The trichobothrium db on the fixed finger of the pedipalp is located between trichobothria est and esb in the Lebanese specimens, as in the specimens from Turkey. On the other hand, the trichobothrium db is closer to trichobothrium est compared to specimens from the Turkish population.
The species Aegaeobuthus nigrocinctus (Ehrenberg, 1828) (Karataş 2007), Compsobuthus schmiedeknechti Vachon, 1949 (Varol et al. 2006) and Scorpio kruglovi Birula, 1910(Roewer 1943 are also distributed in the Hatay province (Turkey) and in Lebanon as well. The presence of these species in both Hatay and Lebanon indicates that faunal similarities exist between these regions, which are both in the Levant and share ecologically similar characteristics. The true relationship between the L. abdullahbayrami populations should be determined through future phylogenetic studies, a task facilitated by the availability of mitochondrial DNA sequences from the specimens from Turkey (Ayhan et al. 2018).
Vachon (1966), Fet & Lowe (2000) and El-Hennawy (2013) listed Leiurus hebraeus as the only species belonging to the genus Leiurus that inhabits Lebanon. The present study provides evidence of a second Leiurus species in Lebanon, showing that the genus is probably undersampled in the region.
Severe cardiac alterations and acute pulmonary edema in children envenomed by L. abdullahbayrami attest to its very high venom toxicity towards humans (Dokur et al. 2017, Aslan et al. 2018, Yöntem et al. 2020, which correlate with the species' venom LD 50 in mouse bioassays, the lowest among all species of the genus Leiurus thus far determined. Therefore, L. abdullahbayrami is potentially one of the medically most relevant scorpion species in the Middle East. Considering that significant venom divergence between Leiurus quinquestriatus and Leiurus hebraeus has been report ed (Nascimento et al. 2006, Smertenko et al. 2001), a fact that may limit the neutralization spectrum of therapeutic antivenoms available in the Middle East (Amr et al. 2021), knowledge of the current distribution of medically important scorpion species is of public health interest in this region. Given that fatal scorpion stings in children -by as yet unidentified specimens -have occurred in areas of Lebanon (Brital, Bekaa), where L. abdullahbayrami is present (e.g. https://www. albawaba.com/news/lebanese-kid-dies-after-scorpion-sting-amid-medicine-shortages-1440607), it seems possible that this species has been involved in such cases. Local health administration should therefore take the presence of this highly venomous species in Lebanon into account. As a consequence, further investigations to reveal the current distribution of L. abdullahbayrami in Lebanon should be carried out. The appropriate medical infrastructure for the local human communities should be set up, which might prevent further fatalities, especially among children.