Although the nymph and subimaginal genitalia of Chinese caenid species Brachoculis acutalis (Zhou, Sun, and McCafferty, ) have been reported, the imago of this species is unknown. Here the reared imagines and photographed nymphs show that this species has a long series of apomorphies and mixed characters between Brachycercinae and Caeninae. Specifically, in nymph, it has three-segmented maxillary and labial palpi, spiny robust body and triangular prosternum. In imago, it has deep brown body, wing base pigmented grey to brown, two independent intercalaries between CuA and CuP, vestigial projections of terga III-IX, forceps with flat base but tapered apex and egg without cap. These features show this species may represent the prototype of the Caenidae.
A new species of the genus Acroneuria Pictet, 1841 of the tribe Acroneuriini, namely Acroneuria lashihaiensis sp. n., is described and illustrated from Yunnan Province of China. Morphological differences between the new species and known congeners are indicated. A key of Acroneuria is provided for males of the 19 known Asian species.http://zoobank.org/urn:lsid:zoobank.org:pub:1DD2532C-9C6B-4469-BD3A-27A69A8DC684
Our study provides new records and a holistic view on distribution and habitats of Prosopistoma pennigerum (M & uuml;ller, 1785) and P. cf. pennigerum in the European part of Russia. In this region, according to the literature data, P. pennigerum has been reported from Tverskaya Oblast' and the Republic of North Ossetia-Alania. Between 2006 and 2022 the authors collected about 3390 macrozoobenthos samples from the European part of Russia, and the genus Prosopistoma Latreille, 1833 was found in less than 0.5% of the samples, which reflects the scarcity of this mayfly. Herein, we publish first records of P. pennigerum from Smolenskaya Oblast' (Western Dvina) and of P. cf. pennigerum from Krasnodarskiy Kray and Republic of Adygea based on the material from the Kuban' River basin. Further, we provide additional records of P. pennigerum from Tverskaya Oblast' (Volga River). Therefore, at present in the European part of Russia, the genus Prosopistoma is known from catchments of the Caspian Sea (Volga, Terek), the Baltic Sea (Western Dvina) and the Azov Sea (Kuban'). The problems of species identification of the material collected in Southern Russia are briefly discussed.
A new stonefly species, Neoperla tumidospina sp. n., is described from the Guangxi Zhuang Autonomous Region in southern China, placed in the subgenus Neoperla (Formosita), and compared to similar taxa. Neoperla (F.) diehli Sivec, 1985 is recorded from Guangxi for the first time. Neoperla (F.) furcostyla Li and Qin, 2013, described from the Mt. Damingshan, Guangxi, is rediscovered in its type locality 13 years after its description. Colour photographs are provided for these species, as well as data on their habitat areas and distributions.http://zoobank.org/urn:lsid:zoobank.org:pub:DAFC8C5C-1732-4A51-94E9-A7A909315C4E
The movement of organisms within river ecosystems has been understood mainly in terms of three dimensions: longitudinal, lateral, and vertical within the water column. However, little is known about the vertical extent of the aerosphere, which is utilised by adult aquatic insects. In this study, vertical adhesive traps were installed on a 59 m-high bridge spanning a mountain stream to investigate a community consisting of adult mayflies, stoneflies, and caddisflies that utilised the aerial zone directly above the river. The results showed that a single female Stenopsyche marmorata Nav & aacute;s, 1920 was captured at a height of 55 m, however, adult insects were concentrated within the zone up to 25 m above the water surface. These observations make a significant contribution to knowledge regarding the flight altitude of adult Ephemeroptera, Plecoptera, and Trichoptera in river ecosystems. Our findings thus indicate that the functional boundaries of river ecosystems can extend to aerosphere. Our article aims to provide new perspectives for re-evaluating conservation strategies for riverine ecosystems, including in relation to the dispersal ecology of aquatic insects and the fragmentation of 'aerial corridors' by artificial structures such as dams.
