Myrmecaelurus, A.Costa, 1855

Kaur, Simarjit, Rajmohana, K. & Pandher, Manpreet Singh, 2019, Morphological studies on male and female genitalia of Myrmecaelurus acerbus (Walker, 1853) (Neuroptera: Myrmeleontidae), Records of the Zoological Survey of India 119 (4) : -

Genus Myrmecaelurus Costa, 1855 belongs to tribe Myrmecaelurini of family Myrmeleontidae and is represented by four species namely Myrmecaelurus acerbus ( Walker, 1853) , Myrmecaelurus afghanus Kimmins, 1950 , Myrmecaelurus implexus ( Walker, 1853) and Myrmecaelurus zigan Aspöck, H. et al., 1980 in the Indian subcontinent ( Chandra & Sharma, 2009; Oswald, 2019). In general, Myrmecaelurus larvae are facultative pit-builders, performing both characters of pit-builders and non-pit-builders (Devetak et al., 2013) whereas the adults like other Myrmeleontids, could be encountered in vegetation during early morning or in dusk.

M. acerbus is the most common species found in India. This species was described by Walker in 1853, under genus Myrmeleon Linnaeus from North India without mentioning any type locality. However, MacLachlan (1868) included this under the genus Myrmecaelurus . According to Krivokhatsky et al. (2015) M. acerbus is a variable species which varies in size and is polymorphous in the intensity of the mottling of the wing venation even within local population. They synonymized variable forms of this species viz., M. varians Navás 1913 , M. aequans Navás, 1913 and M. nematicus Navás, 1932 with M. acerbus . This species has been reported from various localities in India i.e. Bihar, Punjab and Western Himalayas ( Needham, 1909) and different parts of Rajasthan ( Ghosh, 1977).

Although many workers ( Walker, 1853; Navás, 1913; Esben-Petersen, 1918 -19; Asana & Makino, 1937; Holzel, 1968) have dealt with this species, the present manuscript provides for the first time, a detailed description of both male and female genitalia based on scanning electron microscopic studies. The different types of the sensilla and their possible role have been discussed.

Material and Methods

The adult specimens were collected from different localities of Rajasthan as a part of studies on faunal diversity of Rajasthan Survey programme of ZSI.

The field collected specimens were separated up to species level with the help of keys by Ghosh (2000). The terminology of various structures has been adopted from Badano et al. (2017) and Nowińska and Brożek (2017). The morphology of male and female genitalia was studied under stereoscopic microscope as well as Scanning Electron Microscope (SEM). For the preparation of male and female genitalia, the terminal abdominal segments were removed and put in 10% KOH solution overnight. These were then washed in water and kept in solution of 80% alcohol with a drop of glycerol for observation. They were then either processed for SEM or photography under microscope.

Samples used for SEM were dehydrated in graded series of alcohol and mounted on SEM specimen stubs using a small strip of double-sided adhesive tape. They were then sputter coated with gold and scanned under Zeiss EVO 18 special edition.

Photographs were taken under a stereoscopic zoom microscope Leica M250A with a mounted digital camera Leica DFC 500 and processed with LAS v3.7 software. Finally photographic plates were prepared in Adobe© Photoshop© 10.