Overview of the Caucasian Perla Geoffroy, 1762 (Plecoptera: Perlidae) based on morphological and molecular data with description of two new species Author Teslenko, Valentina A. Federal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch, Russian Academy of Sciences (FSC EATB FEB RAS), 690022, Vladivostok, Russia. Author Palatov, Dmitry M. Severtsov A. N. Institute of Ecology and Evolution of RAS, 33 Leninsky prospect, 119071 Moscow, Russia. Author Semenchenko, Alexander A. 0000-0001-7207-9529 Federal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch, Russian Academy of Sciences (FSC EATB FEB RAS), 690022, Vladivostok, Russia. semenchenko_alexander@mail.ru text Zootaxa 2024 2024-09-11 5507 1 1 56 http://dx.doi.org/10.11646/zootaxa.5507.1.1 journal article 10.11646/zootaxa.5507.1.1 1175-5326 13747718 065ECECA-5F0B-47BE-82FC-6C1F68B316FD Key to Caucasian Perla species based on male penial setae patterns 1 Sac of the penis dorsomedial bears a tongue-shaped lobe covered with a relatively wide apical brush; the spines of the brush along the lateral edges of the sac are absent ( Figs. 77−79 , 108−111 )..............................................2 − Sac bears a narrow apical brush ( Figs. 9−10 ).................................................................3 2 Tube of the penis with constriction in the distal 1/3 before the sac; the sac is large, 1/3 wider than the tube, and covered with a loose triangular apical brush ( Figs. 108−111 ). North Caucasus. Russia , Krasnodar Kray . Armenia , Georgia , Azerbaijan , and Turkey . Up to 2000 m . Adult presence: May–August............................... P. pallida Guérin-Méneville, 1843 − Tube of the penis without constriction; the sac width is the same as the tube width; ventrally, the sac is deeply depressed ( Figs. 77−79 ). Russia , Krasnodar Kray the Black Sea coast of the Caucasus from Tuapse to Sochi. Up to 200 m . Adult presence: July............................................................................ Perla schapsugica sp. nov . 3 Sac is membranous, without tiny setae ( Figs. 34−35 )......................................................... 4 − Sac is membranous and covered with tiny setae ( Figs. 139−140 , B, D).............................................5 4 Sac bears a narrow apical brush; additional ventral brush is absent ( Figs. 33−35 ). Caucasus. Russia , North Ossetia-Alania. Iran , Alborz Mountains . 1770−1900 m . Adult presence: June−July.................................. Р. persica Zwick, 1975 − Sac bears a narrow apical brush and an additional small ventral brush ( Figs. 10 , C). North Caucasus. Russia : Adygea, KarachayCherkessia, North Ossetia-Alania, Krasnodar Kray. Abkhazia . Georgia . Adult presence: late May–August...................................................................................... P. caucasica Guérin-Méneville, 1843 5 Sac covered with tufts of tiny setae associated with patches and arranged in concentric lines, following the shape of the lobes ( Figs. 139−140 , B, D). North Caucasus. Russia , Krasnodar Kray . Up to 1800 m . Adult presence: June.................................................................................................... Perla palatovi sp. nov . − Sac covered with dense, tiny setae spaced relatively evenly ( Figs. 58 , D). Armenia , Azerbaijan . 1400–1850 m . Adult presence: latter half of May−first half of July............................................... P. kiritshenkoi Zhiltzova, 1961