Journal of Threatened Taxa | www.threatenedtaxa.org | 26 November 2019 | 11(14): 14906–14907
A new distribution record of the gall midge Octodiplosis bispina Sharma (Diptera: Cecidomyiidae) from the Western Ghats of Tamil Nadu, India
Duraikannu Vasanthakumar 1, Radheshyam Murlidhar Sharma 2 & Palanisamy Senthilkumar 3
1,2 Zoological Survey of India, Western Regional Centre, Akurdi, Pune, Maharashtra 411044, India.
3 Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamilnadu 603203, India.
1 firstname.lastname@example.org (corresponding author), 2 email@example.com, 3 firstname.lastname@example.org
Gall midges are small, inconspicuous flies, but they may be very important in both forest and agro ecosystems. The body of the adult gall midges generally varies from 0.5–3 mm in length but occasionally may be as long as 8mm or less than 0.5mm. They usually have long antennae. The wing veins are reduced in number with only three or four veins normally present. Tibial spurs are absent. The larvae vary somewhat in their habits but most species are either phytophagous, producing galls on various plants, mycophagous, feeding on fungi, or zoophagous, feeding on invertebrates, especially insects (Skuhrava et al. 1984). While identifying the collections of gall midges of Tamil Nadu State, we came across a gall midge species identified as Octodiplosis bispina Sharma, 1987. Perusal of published works on the gall midges of Tamil Nadu and the Western Ghats (Sharma 2009) revealed that this species has not been reported from these areas earlier and hence the present collection forms a new distribution records (Figure 1). The adults were dissected and mounted on microscope slides in Canada balsam and the specimens were deposited in the National Zoological Collection of WRC, Zoological Survey of India, Entomology Section, Pune, India.
Material examined: Ent 10/179, 2 males, 17.i.2018, collected at light, near Maruthamalai, Coimbatore, Tamil Nadu, coll. D. Vasanthakumar. Ent 10/214, 2 males, 23.v.2018, collected at light, near Courtallam, Tirunelveli District, Tamil Nadu, coll. P. Senthilkumar.
Distribution: Aurangabad (Maharashtra), the Andaman Islands, and Tamil Nadu (this study).
Diagnostic Characters: Palpi quadriarticulate. Antenna with 2+12 segments, the flagellate antennal segments binodose in male (Image 1A), with long apical stems, enlargements with two whorls of long setae, one on each enlargement, with three whorls of regular circumfila, one on basal and two on apical enlargements; middle whorl shortest; wing, narrow, three times as long as broad (Image 1B); vein R1 joining costa a little before the basal ¼ of the wing; vein Rs present, vein R5 reaching wing margin well beyond the apex and interrupting costa at its union, vein Cu forked. Claw, simple on all legs, curved, empodium rudimentary. Genitalia (Image 1C), Gonocoxite, with a median bilobed obtuse lobe, length 2.33 x its maximum thickness; gonostylus slender, curved, gradually tapering towards the tip, ending in tooth. Dorsal plate deeply bilobed, lobes triangular, rounded apically, narrowed medially, aedeagus slender, narrowed medially with a pair of strong, lateral upwardly or downwardly directed spines beyond middle, tip capitate (Sharma 1987).
Skuhrava, M., V. Skuhravy & J.W. Brewer (1984). Biology of Gall midges, pp. 169–222. In: Ananthakrishnan, T.N. (ed.). Biology of Gall Insects. Oxford & IBH Publishing Co. India, 362pp.
Sharma, R.M. (1987). On a new species of genus Octodiplosis Giard (Diptera: Cecidomyiidae) from India. Geobios new reports 6: 2–4.
Sharma, R.M. (2009). Insecta: Diptera: Cecidomyiidae. Zoological Survey of India, Fauna of Tamil Nadu, State Fauna Series 17: 111–113.