Russian Journal of ZoologyRussian Journal of ZoologyЗоологический журнал0044-51343034-5456The Russian Academy of Sciences70043310.7868/S3034543X25110026ARTICLESСтатьиResearch ArticleBRYOCAMPTUS (BRYOCAMPTUS) OESCULUS SP. N. (COPEPODA, HARPACTICOIDA) FROM THE HYPORHEIC COMPLEX OF THE ISKAR RIVER, BULGARIABRYOCAMPTUS (BRYOCAMPTUS) OESCULUS SP. N. (COPEPODA, HARPACTICOIDA) ИЗ ГИПОРЕЙНОГО КОМПЛЕКСА РЕКИ ИСКАР, БОЛГАРИЯhttps://orcid.org/0000-0001-8712-9066ApostolovA. MАпостоловА. Мapostolov2003@abv.bg1511202510411VOL 104, NO11 (2025)ТОМ 104, №11 (2025)152908012026Copyright ©; 2025, Russian Academy of SciencesCopyright ©; 2025, Российская академия наук2025Russian Academy of SciencesРоссийская академия наукhttps://rjsvd.com/0044-5134/article/view/700433

Material of a Bryocamptus species, formerly referred to as Bryocamptus (Bryocamptus) aquaeductus Borutsky, 1934 from Bulgaria, is here recognized as a distinct new species. Specimens were recently obtained from a hypotheic zone of Iskar River, near the town of Koynaré, Bulgaria, from the bottom substrate represented by gravels of alluvial origin. Among the species in the subgenus Bryocamptus, the new species Bryocamptus (Bryocamptus) oesculus sp.n. most closely resembles Bryocamptus (Br.) aquaeductus, but it clearly differs from the type population from Ciscaucasia by the setal formula of P1–P4 and differences at the level of microcharacters, integumental sensilla and pores, and pores on the swimming legs. Similarity to other species of the pygmaeus–typhlops group is discussed, along with brief comments on the morphological similarities and differences between the new species and other species of this group. A brief ecological description and notes of the variability of the species are given.

Материал вида Bryocamptus, ранее описанного как Bryocamptus (Rheocamptus) aquaeductus Borutsky, 1934 из Болгарии, здесь рассматривается как отдельный новый вид. Образцы были недавно получены из гипорейной зоны реки Искар, недалеко от города Койнаре, Болгария, из донного субстрата, представленного гравием аллювиального происхождения. Среди видов подрода Bryocamptus новый вид Bryocamptus (Br.) oesculus sp. n. наиболее близок к Bryocamptus (Br.) aquaeductus, но имеет отчетливые отличия от типовой популяции из Предкавказья по формуле щетинок P1 – P4 и отличия на уровне микропризнаков, интегументальных сенсилл и пор, а также пор на плавательных ногах. Обсуждается сходство нового вида с другими представителями группы pygmaeus–typhlops, даются краткие комментарии о его отличиях от видов этой группы. Приводятся краткая экологическая характеристика и данные об изменчивости вида.

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