The life cycle of the cladoceran Simocephalus acutirostratus has been studied in the laboratory with reference to its total life span, duration of instars, egg production and growth. It has four pre-adult and eighteen adult instars and produces about 248 eggs during a mean life span of 44 days within a temperature range of 28°C-30°C. Egg production was found to be bimodal, with a sharp decline towards the end of the life cycle. The present results are compared and discussed with those of other tropical and temperate daphnids. It has been shown that while this species resembles most other daphnids {D. middendorffiana, D. pulex, D. carinata) in the growth pattern of pre-adult instars, it resembles the temperate D. pulex in having a relatively long life span, relatively high egg production and slow rate of growth.While studies on embryonic development of S. acutirostratus resemble the growth stages of the temperate Daphnia magna, there are differences in the total period of development between the two species. In the latter aspect, however, the present species closely resembles other tropical daphnids.

Two new genera and five new species of teloganodid mayflies (Ephemeroptera: Pannota: Ephemerelloidea) are described based on larvae from south India: Janohyphella indica, n. gen., n. sp., Indoganodes jobini, n. gen., n. sp., Teloganodes sartorii, n. sp., Dudgeodes palnius, n. sp., and Derlethina tamiraparaniae, n. sp.  Janohyphella, n. gen., is distinguished from the larvae of other teloganodid genera by having a combination of three subequal caudal filaments, lamellate gills on abdominal segments II through V and posterolateral processes well-developed on abdominal segments II through IX, except III. Indoganodes, n. gen., is distinguished from the larvae of other teloganodid genera by having three subequal caudal filaments, lamellate gills on abdominal segments II through VI, posterolateral projections weakly developed on abdominal segments I through V, but distinct on segments VI through IX. Our new species of Dudgeodes Sartori, 2008 and Derlethina Sartori, 2008 represent the first discoveries of these genera outside Southeast Asia, with the latter genus previously considered endemic to Borneo. Emendations to the larval species key of known Oriental Teloganodidae are provided. We hypothesize that the occurrence of the new taxa in southern India is a result of the tectonic events associated with the split-up of Gondwana. This illustrates the profound biogeographical significance of how vicariance led to the establishment of some distinct oriental lineages initially on the rafting Indian Deccan Plate, which might have triggered dispersal events for subsequent species diversification in Southeast Asia.

The impact of riparian land use on the stream insect communities was studied at Kudremukh National Park located within Western Ghats, a tropical biodiversity hotspot in India. The diversity and community composition of stream insects varied across streams with different riparian land use types. The rarefied family and generic richness was highest in streams with natural semi evergreen forests as riparian vegetation. However, when the streams had human habitations and areca nut plantations as riparian land use type, the rarefied richness was higher than that of streams with natural evergreen forests and grasslands. The streams with scrub lands and iron ore mining as the riparian land use had the lowest rarefied richness. Within a landscape, the streams with the natural riparian vegetation had similar community composition. However, streams with natural grasslands as the riparian vegetation, had low diversity and the community composition was similar to those of paddy fields. We discuss how stream insect assemblages differ due to varied riparian land use patterns, reflecting fundamental alterations in the functioning of stream ecosystems. This understanding is vital to conserve, manage and restore tropical riverine ecosystems.

The Cincticostella insolta complex (Ephemeroptera: Ephemerellidae) is reviewed based on new and historic material, as well as new field observations. Three new species are described viz., C. richardi Martynov & Palatov, sp. nov. and C. ranga Selvakumar & Subramanian, sp. nov. from India, and C. sivaramakrishnani Martynov & Palatov, sp. nov. from Nepal. A correction of the original description and some additional distinguishing features are given for C. braaschi Jacobus & McCafferty, 2008. Cincticostella insolta (Allen, 1971), C. braaschi and C. bifurcata Xie, Jia, Chen, Jacobus & Zhou, 2009 are recorded from the Indian subregion for the first time. Summaries of known distribution data and habitat preferences, as well as larval diagnoses, are presented for all seven species of the complex.

The concept of the Cincticostella nigra (Uéno, 1928) (Ephemeroptera: Ephemerellidae) complex is clarified and Indian and Nepali representatives of the complex are reviewed. Four new species are described viz. Cincticostella changfai Martynov & Palatov, sp. nov., Cincticostella funki Martynov, Selvakumar, Palatov & Vasanth, sp. nov., Cincticostella shinichii Martynov & Palatov, sp. nov. and Cincticostella wangi Selvakumar, Martynov & Subramanian, sp. nov. The larva of C. corpulenta (Braasch, 1981) is re-described, based on the holotype and paratypes. Cincticostella gosei (Allen, 1975) is recorded from India for the first time. Morphological differences of the species complexes of Cincticostella Allen, 1971 are analysed. A new species complex, Cincticostella gosei complex, is proposed. Summaries of distribution data and habitat preferences, as well as new larval diagnoses, are presented for all species of the Cincticostella nigra complex.