Anatolichthys irregularis Common name. Kaklık killifish. Diagnosis. Distinguished from other species of Anatolichthys by: ● male with irregularly set and shaped, dark-brown bars, bars with white spots or vermiculate pattern, some large individuals plain, dark-grey with some yellow blotches / ○ male with yellow or white anal with narrow black margin / ○ female with numerous black, irregularly shaped stripes and vermiculate blotches on flank organised in midlateral rows / ○ body completely covered with overlapping scales. Size up to about 52 mm SL. Distribution. Türkiye: Spring near Kaklık in Büyük Menderes drainage. Habitat. Springs with dense vegetation and associated streams. Biology. Live up to 3 years; biology as described in genus section. Conservation status. CR; known only from a very small spring area, vulnerable to climate change, recreational activities, non-native species and desiccation. Remarks. Anatolichthys irregularis is very closely related to A. maeandricus, but the colour pattern of male and female can easily distinguish both species. It is likely that A. irregularis was recently isolated and has adapted to the gypsum springs where it lives. Further reading. Yoğurtçuoğlu & Freyhof 2018 (description).

Published as part of Freyhof, Jörg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, GmbH, Berlin / Boston :De Gruyter on page 707, DOI: 10.1515/9783111677811, http://zenodo.org/record/17881367