Sandracottus vijayakumari (Coleoptera: Dytiscidae), a new aquatic beetle species from landslide hit area of Nelliyampathy Forest Range, Western Ghats, Kerala, India

The present study deals with the description of a new species Sandracottus vijayakumari from Nelliyampathy forest range, southern Western Ghats, Kerala, India with a comparative key of closely related species S. dejeani Aube, 1838. Only one species is known from the genus Sandracottus Sharp, 1882, from southern Western Ghats, Kerala. The Nelliyampathy forest areas are hilly and the altitude of the hills range 40–1,530 m. The region experiences several types of landslides especially during the monsoon (August to September 2018). The new species was discovered in one of the worst landslide hits area in Nelliyampathy forest, Kundrachola region. The new aquatic beetle species is moderately large in size and often very attractively marked dorsally with complex maculations. Additionally, the new species shows a strong synapomorphy along with Eretini, Hydaticini, and Aubehydrini tribes.

Review of the New World Notomicrus Sharp (Coleoptera, Noteridae) I: Circumscription of species groups and review of the josiahi group with description of a new species from Brazil

The New World species of the minute aquatic beetle genus Notomicrus Sharp compose a much greater diversity than their Old World congeners, with 14 of the 17 known Notomicrus species occurring in the Neotropics. A recent phylogenetic study recovered four primary New World species groups and found that there are a number of undescribed species across all of these main lineages. Here, we provide a taxonomic key to these New World species groups, including two described species that we currently do not place in any group (“incertae sedis” species), complete with images and illustrations of diagnostic characters and taxonomic notes including a list of known species in each group. This work provides a scaffold for further planned taxonomic revisions within the genus. In addition, we review the first of the four New World groups, the josiahi species group and describe one new taxon, N. interstinctussp. nov. from northern Brazil. Provided are descriptions, habitus images and illustrations of diagnostic characters.

New records of water beetles (Coleoptera) in the territories of Udmurtiya and Bashkiriya

This publication serves as a continuation of the inventory of aquatic beetle faunas in the Udmurtiya and Bashkortostan, a summary of which was published in 2020. The known composition of the faunas of the republics at the time of the study consisted of 230 (for Udmurtiya) and 120 (for Bashkiriya) species of aquatic beetles (including Donaciinae and Bagoiinae). The material for the article was the collections carried out in the framework of the study of the macrozoobenthos of rivers, oxbow lakes and temporary waterbidies from 2019 to 2020. Sampling of adults and beetle larvae from substrates submerged in water (stones and wood) was carried out manually. When collecting aquatic organisms in overgrown water bodies and rivers, a hydrobiological scraper was used. Data on the first finds of 5 species from 5 families in the territory of Udmurtiya and 6 species from 4 families in Bashkiriya are given. They are respectively as following: Orectochilus villosus (Gyrinidae), Haliplus confinis (Haliplidae), Rhantus bistriatus (Dytiscidae), Helophorus redtenbacheri (Helophoridae), Limnebius crinifer (Hydraenidae) in Udmurtiya, and Haliplus varius (Haliplidae), Ilybius fenestratus, Hydroporus palustris, Graptodytes bilineatus (Dytiscidae), Helophorus brevipalpis (Helophoridae), Limnebius cf. parvulus (Hydraenidae) in Bashkiriya.

Model of disharmonic succession of dystrophic lakes based on aquatic beetle fauna (Coleoptera)

Directional changes in environmental conditions during individual stages of the succession of lakes should determine the character of the aquatic beetle fauna inhabiting them. Can changes in environmental conditions lead to degradation of fauna and to a deterioration of the ecological quality of lakes? We analysed this problem in 40 lakes. The fauna of the lakes proved to be rich and diverse in terms of species. Deterioration of species richness along successional stages was not observed, but distinct changes were noted in faunal composition. The eurytopic component proved stable, whereas changes in specialised components (i.e. lake and river species and tyrphophiles) were of key importance. The formation of beetle communities in the lakes was influenced to a greater extent by environmental factors, namely substrate, macrophyte structure and Sphagnum mat cover, than by the physical parameters of the water (pH, saturation or conductivity). The lakes proved to be of considerable ecological value. Regardless of the stage of succession, they are a habitat for numerous species, including rare and endangered ones. Hence, on the one hand humic lakes play an important role in local biodiversity, whereas on the other hand they may be perceived as refuges for species in environments that could be restored as a result of beneficial measures.

Factors affecting aquatic beetle communities of Northern Western Ghats of India (Arthropoda: Insecta: Coleoptera)

We studied faunistic and ecological factors influencing distributions of aquatic beetles in the Northern Western Ghats (NWG) of India. In the period 2013–2017, we collected 213 samples from 105 localities within the area and obtained 66 species, the majority of which belong to Dytiscidae. Relative occurrence based on incidence data revealed that dytiscid water beetleLaccophilus inefficiensas the most widespread species. Non-parametric richness estimators Chao2, Jackknife1 and Bootstrap showed that 70–80% of the fauna was covered in the sampling efforts from different types of freshwater habitats. Sample-based rarefaction suggested that more sampling efforts within the region can yield additional species. Canonical correspondence analysis (CCA) revealed that altitude, salinity, hydroperiod and depth influenced the distribution of aquatic beetles. Further, CCA also revealed habitat preference and co-occurrence of various aquatic beetle species. For instance, while co-occurring species under Laccophilinae and Hydroporinae were eurytopic, other co-occurring speciesClypeodytes hemani,Microdytes sabitaeandLacconectus lambaiwere restricted to temporary habitats. Multiple correspondence analysis (MCA) showed a strong association between altitudinal classes and species distribution where many species were restricted within a particular altitudinal gradient. For example,M. sabitae,C. hemani,Hygrotus nilghiricus,L. lambaiandRhantus taprobanicuswith classes 900–1199 and 1200–1499 whileHyphydrus flavicans,Laccophilus ceylonicus,Lacconectus andrewesi,Sternolophus inconspicuusandCanthydrus laetabiliswith the class 300–599. The present work on aquatic beetles is the first attempt to study the influence of environmental factors on species diversity and distribution in the Northern Western Ghats of India.