27. Culex (Culex) torrentium Martini, 1925 (Fig. 4H) Published sources: Remm (1057: 157, as Culex exilis Dyar, 1924), Burtin (2014: 40), Kirik et al. (2021: 11, as Cx. (Cux.) pipiens / torrentium). Voucher material: 1♀, Tartu (58° 22′ 17″ N, 26° 41′ 58″ E), 27.IX.2016, H. Kirik leg., H. Kirik det., sweep net, IZBE0210228, GenBank: OK465178; 1♀, Tartu (58° 23′ 40″ N, 26° 44′ 05″ E), 08.IX.2016, H. Kirik leg., H. Kirik det., sweep net, IZBE0210229, GenBank: OK465179; 1♂, Tartu (58° 23′ 44″ N, 26° 43′ 44″ E), 27.IX.2016, H. Kirik leg., H. Kirik det., sweep net, IZBE0210245. Comment: The adult females of Cx. torrentium are difficult to distinguish from Cx. pipiens based on only morphological characteristics. Of 12 females subjected to DNA barcoding, seven (58.3%) were identified as Cx. torrentium. Adult males of the two species can be distinguished based on structures of their genitalia. In 2013, 68 (51.5%) among 132 males were identified as Cx. torrentium. In 2017, only 54 (39.1%) males were determined to be Cx. torrentium compared to 84 (60.9%) of individuals identified as Cx. pipiens. All things considered, it is reasonable to assume that Cx. torrentium makes up about half of the 1,236 (5.1% of all collected mosquitoes collected) identified as Cx. pipiens / torrentium during in this study. However, the true relative abundance of these mosquitoes may have been underestimated in this study due to collection bias. Culex torrentium and Cx. pipiens are most active at the end of summer, when they become dominant. Seven Cx. torrentium caught in Estonia were analyzed for Wolbachia pipientis using the wsp gene for detection. The results were negative, which is in line with the findings of Bergman & Hesson (2021).

Published as part of Kirik, Heli, Tummeleht, Lea & Kurina, Olavi, 2022, Rediscovering the mosquito fauna (Diptera: Culicidae) of Estonia: an annotated checklist with distribution maps and DNA evidence, pp. 261-287 in Zootaxa 5094 (2) on page 272, DOI: 10.11646/zootaxa.5094.2.3, http://zenodo.org/record/5965149