Morphological abnormalities in ticks (Acari: Ixodidae) feeding on humans in Central Black Sea region, Turkey

Abstract

During our parasitological studies on ticks infesting humans, we noticed 127 ticks with abnormal morphology. Some of these specimens had local abnormalities including the absence of one or two legs, one porose area, one spiracle, while others had also general abnormalities such as asymmetric body, gynandromorphism, gigantism or caudal constriction. Most encountered tick species with abnormalities observed were Hyalomma marginatum (n = 113, 88.97 %), followed by Hyalomma excavatum (n = 3, 2.36 %) and Rhipicephalus turanicus (n = 3, 2.36 %). Atrophy or lack of the one adanal plate (n = 49, 38.58 %) was the most encountered local abnormalities. Other local abnormalities were atrophy or lack of one leg (n = 36, 28.35 %) and atrophy or lack one spiracle (n = 11, 8.66 %). The most encountered general abnormalities were asymmetry (n = 9, 7.08 %), constriction (n = 5, 3.93 %) and gynandromorphism (n = 4, 3.15 %), respectively. In the present study, morphological abnormalities in ticks collected on humans were investigated in detail for the first time and many forms of morphological abnormalities were reported for Turkey.

General and Local Morphological Anomalies in Amblyomma lepidum (Acari: Ixodidae) and Rhipicephalus decoloratus Infesting Cattle in Uganda

“…Chitinous formations were also observed in Hyalomma asiaticum (Delpy 1936), Ornithodoros tartakovsky (Pavlovsky 1940), Hyalomma dromedarii (Alfeief 1948) and Ixodes ricinus (Campana-Rouget 1959b). Constrictions have been reported in Hyalomma marginatum (Keskin et al 2016), A. cajennense and Amblyomma parvum (Guglielmone et al 1999).…”

“…Gynandromorphism is a rare event in which both female and male phenotypic characteristics are simultaneously displayed in an organism (Campana-Rouget 1959b, Guglielmone et al 1999, Keskin et al 2012, Keskin et al 2016). Despite growing trend in medico-veterinary research on ticks (Moyer 2015, Laroche et al 2017), to date, approximately 81 natural cases of gynandromorphic ticks have been documented in Ixodidae (Labruna et al 2000, Labruna et al 2002, Keskin et al 2012, Kar et al 2015, Prusinski et al 2015, Keskin et al 2016, Chitimia-Dobler et al 2017, Muñoz-Leal et al 2018). Nevertheless, gynandromorphism is relatively frequent in natural populations of Amblyomma ticks, as compared with other genera (Labruna et al 2002, Keskin et al 2012, Keskin et al 2016, Muñoz-Leal et al 2018).…”

“…Tick anomalies were first described over 100 years ago (Neumann 1899), and have since been reported in species belonging to the genera Argas , Ornithodoros , Amblyomma , Dermacentor , Haemaphysalis , Hyalomma , Ixodes , and Rhipicephalus (Siuda 1981; Taylor et al 1991a, b; Guglielmone et al 1999; Labruna et al 2000; Labruna et al 2002; Keskin et al 2012; Kar et al 2015; Keskin et al 2016). Gynandromorphism, defined as an individual possessing both male and female phenotypic characters (Eritja 1996), is described and reported for a series of hard tick species (Campana-Rouget 1959a,b; Keskin et al 2012; Nowak-Chmura 2012; Larson and Paskewitz 2016), and represents the most documented abnormality in ticks (Labruna et al 2000, Labruna et al 2002, Keskin et al 2012, Prusinski et al 2015, Keskin et al 2016, Chitimia-Dobler et al 2017, Chitimia-Dobler and Pfeffer 2017, Muñoz-Leal et al 2018). In addition, other anomalies such as body asymmetry, atrophy, ectromely, fusion of adanal plates and festoons, have also been reported (Campana-Rouget 1959a, Guglielmone et al 1999, Dergousoff and Chilton 2007, Kar et al 2015, Keskin et al 2016, Chitimia-Dobler et al 2017).…”

Abnormal Development of Hyalomma Marginatum Ticks (Acari: Ixodidae) Induced by Plant Cytotoxic Substances

“…Not only prolonged feeding, reduced body weight, and reduced reproductive potential [70,71,72], but also morphological changes were detected in subsequent developmental stages in ticks [71,73]. Most often, however, the causes of anomalies in ticks in laboratory cultures [74,75,76,77,78,79] and in nature [37,38,39,80,81,82,83,84,85,86,87,88,89] are still undetermined.…”

Türkiye’den Yeni Teratolojik Kene (Acari: Ixodidae) Örnekleri

“…This remarkable phenomenon occurs at relatively low frequencies in nature (Balazuc 1948;Campana-Rouget 1959a,b). Many authors have documented teratological specimens of various arthropods including insects, ticks and other arthropods (Balazuc, 1948;Keskin et al, 2016;Popovici et al, 2014). However, there is still a gap in the literature concerning teratological changes in ticks specifically in Turkey.…”