Teratological abnormalities in hard ticks (Acari: Ixodidae) from Pakistan

Studying teratological abnormalities in ticks are taxonomically important because this poorly understood biological phenomenon causes difficulties in tick's identification. Globally, reports regarding these abnormalities in ticks, reasons of their causes and their impacts are scarce. According to the available published data, there are no studies regarding teratological abnormalities in ticks from Pakistan. Herein, ticks examined for these abnormalities were museum deposited, collected from buffalos, cattle, camels, goats and sheep in 17 districts of Pakistan during 2017-2023. The abnormalities were observed in 88 out of 3279 (2.68%) ticks, representing eight ixodid species (Rhipicephalus microplus, Rhipicephalus turanicus, Rhipicephalus haemaphysaloides, Haemaphysalis bispinosa, Haemaphysalis montgomeryi, Hyalomma anatolicum, Hyalomma scupense, Hyalomma dromedarii). Among abnormal ticks, 67 abnormalities were characterized as local, 12 as general and nine as a combination of both. Local abnormalities were observed in the scutum, palpal segments, anal aperture, spiracular plates, ventral plates, caudal appendage, festoons and posterior grooves. Also, the constrictions and excavations of body parts were observed. General abnormalities included irregular idiosoma and lateral idiosomal bifurcation. This study, for the first time, highlights the diversity of teratological abnormalities in Pakistani ticks, and are reported in in Hy. anatolicum, Ha. bispinosa and Ha. montgomeryi for the first time.