When males and females belong to different genera: an interesting case of Synurella/Pontonyx (Crustacea: Amphipoda: Crangonyctidae) co-occurrence

Abstract

с сильным половым диморфизмом. Однако, используя интегративный подход, мы описываем четыре новых вида, по одному из родов Synurella Wrześniowski, 1877 и Pontonyx Palatov et Marin, 2021 из каждой локации. Обнаруженные виды генетически и морфологически хорошо отличаются от ранее известных видов обоих родов. Несмотря на наличие относительно большого количества материала, он не позволил нам найти особей противоположного пола ни для одного из описанных видов. Мы полагаем, что ряд таких "пар" уже был описан из северной Турции и других районов вокруг Черного моря, где распространен род Pontonyx. Более того, такой пример совместного обитания двух видов крангониктид описан впервые, ранее крангониктиды были найдены вместе с другими стигобионтыми амфиподами, например, нифаргусами (Crustacea: Amphipoda: Niphargidae), но никогда -вместе с другими крангониктидами.

Uralocrangonyx gen.n. (Amphipoda: Crangonyctidae) from the Southern Ural, Russia

“…Such feature is the most striking diagnostic feature of the species and the new genus. A large number of hooks (more than 4) is possibly an ancestral feature [Marin, Palatov, 2021]. However, this new genus can be also separated from Bactrurus by a long (about 3 times as long as wide) outer ramus of uropod III (vs. about 1-1.5 times as long as wide in Bactrurus and Crangonyx s.str.…”

“…Recently, the taxonomic structure of the family Crangonyctidae has undergone a serious revision, mainly due to the possibility of using molecular genetic methods [Kornobis et al, 2011;Copilaș-Ciocianu et al, 2019;Marin, Palatov, 2021]. A number of new genera were erected for previously described species [Sidorov, Holsinger, 2007;Palatov, Marin, 2020;Marin, Palatov, 2021a;Cannizzaro et al, 2021].…”

“…in the Caucasus [Marin, Palatov, 2021b] or Pontonyx spp. in the Colchis Lowland [Marin, Palatov, 2021a]) and genera with a narrow distribution (for example, Volgonyx Marin et Palatov, 2021 in Saratov region [Marin, Palatov, 2021a]), as well as an even larger unexplored territory, it is safe to say that the diversity of the family in the Palaearctic is still far from being completely studied, probably even at the generic level.…”

Diversity of the Caucasian genus Diasynurella Behning, 1940 (Amphipoda: Crangonyctidae) with description of four new species

“…ered as a sister clade of the genus Pontonyx Palatov et Marin, 2021[Marin, Palatov, 2021a. However, the phylogenetic position of both genera is currently not obvious [Copilaș-Ciocianu et al, 2019;Palatov, Marin, 2020;Marin, Palatov, 2021a, b].…”

“…Currently described stygobiotic crangonyctid diversity from the Caucasus is recently increasing, and already includes more than 19 endemic species [Behning, 1940;Derzhavin, 1945;Marin, Palatov, 2021a, b, 2022bPalatov, Marin, 2021;Marin, Palatov, in press], while the actual diversity of the family Crangonyctidae is still far from being completely studied. There are some difficulties of collecting these crustaceans due to their very small size: the body length of adults rarely exceeds 4.5 mm.…”