The katydid country: bioacoustics and ecology of tettigoniid communities from the Indian subcontinent

ABSTRACT

The study provides the first description of acoustic communities from a subtropical rainforest in Northeast India and a previously unexplored site from the Western Ghats. We describe call structures of 15 katydid species from the Indian subcontinent. The habitat and seasonal variations of the communities were investigated at both sites. Most species observed produced ultrasonic broadband calls (bandwidth: 11.07–42.5 kHz); only two Pseudophyllinae members produced pure tone calls. The study includes calls of two previously undescribed species of the genus Ducetia (subfamily: Phaneropterinae) from the subcontinent. We observed diverse acoustic communities at both sites represented by five major subfamilies: Conocephalinae, Hexacentriane, Mecopodinae, Phaneropterinae and Pseudophyllinae. The acoustic communities at each site exhibited seasonal variations and habitat preferences. The post-monsoon season had a richer community composition than the dry season. We compared differences in the community compositions between habitats using a presence–absence matrix based on 526 individuals from the two sites. Species composition was found to be different among habitats (stress = .06, dimension: 2), with ANOSIM indicating separation of species among understorey, shrubland and grassland habitats.

KEYWORDS:

• Acoustic community
• Northeast India
• pure tone calls
• Tettigoniidae
• Western Ghats

Acknowledgements

We thank the anonymous referees for suggestions that greatly improved the manuscript. We would like to thank KG Heller for providing the research articles not accessible previously and for the insights in identification of Ducetia and Mecopoda specimen. We thank State Forest Department, Goa and Assam for permissions to conduct field work in protected areas. We thank Chandrakant Gaonkar & Kamlakant Naik for assistance in the field. We thank Dr. Manisha Tomar and Sunil Kumar for help in field and data collection. SD acknowledges University of Delhi R&D grant and IoE (IoE/FRP/LS/2020/27) grant for funding. CT thanks the Orthopterist Society for a OSF Grant. CT was supported by a fellowship from the University Grants Commission and University of Delhi. We would like to thank Prof. Suman Lakhanpaul, Prof. R.K Tandon and the Department of Botany and University Scientific Instrumentation Centre (USIC), University of Delhi, for their assistance with electron microscope imaging of the stridulatory files.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

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Additional information

Funding

The work was supported by the Orthopterists’ Society [OSF grant], University of Delhi [IoE/FRP/LS/2020/27].