Journal of Threatened Taxa | www.threatenedtaxa.org | 26 August 2018 | 10(9): 12282–12285
A record after 52 years, and additional description of the emesine assassin bug Emesopsis nubila (Hemiptera: Reduviidae: Emesinae) from western India
Balasaheb V. Sarode 1, Nikhil U. Joshi 2, Pratik P. Pansare 3 & Hemant V. Ghate 4
1,2,3,4 Post-Graduate Research Centre, Department of Zoology, Modern College of Arts Science and Commerce, Shivajinagar, Pune, Maharashtra 411005, India
1 firstname.lastname@example.org, 2 email@example.com, 3 firstname.lastname@example.org, 4 email@example.com (corresponding author)
A small, 5mm long, hairy female bug with long legs, till date not recognized by the authors, was collected near a source of light in Katraj area of Pune City, Maharashtra, the western part of India. Subsequently, a similar male specimen was collected in Shirur, near Pune, in a grassy patch. One dead male was also found trapped in a spider’s web at Daund, near Pune. All the three specimens were identified using keys in Wygodzinsky (1966) as Emesopsis nubila Uhler, 1893, which is an emesine assassin bug species belonging to the tribe Ploiariolini and is widely distributed in tropical and subtropical zones all around the world. These specimens represent the first record of E. nubila from Maharashtra State as well as western part of India. An earlier record of this species (as Calphurnia reticulata) was from Calcutta (now Kolkata) (Distant 1910); the checklist of Reduviidae by Ambrose (2006) also states Kolkata as a locality based on Distant’s work and not on the basis of any fresh collections. Thus, this finding is a rediscovery of this bug after a prolonged period and also extends the range of its distribution considerably westwards as far as India is concerned. Although widespread, this bug has not been recorded from India in many years, except perhaps the record by Wygodzinsky (1966) of a specimen from Coimbatore, southern India.
In this note, we provide many images of the morphological characters of this species as we strongly support the idea of Ang et al. (2013) who state in the context of taxonomic papers, “We propose that descriptions should become more data-rich by presenting large amounts of images and illustrations to cover as much morphology as possible”.
Material and Methods
Material examined: one female from Katraj, Pune (coll. M. Joshi; October 2016); one male from Shirur, Pune (coll. B. Sarode, June 2017); one male from Daund, Pune (coll. P. Pansare, November 2017). Bugs were studied under a Leica stereozoom (MZ6) microscope and also photographed with an attached Canon Powershot S50 camera. Several images were stacked using Combine ZM software and the images were processed with Adobe Photoshop CS5. Measurements were done with Erma stage and ocular micrometer and an accurate scale. The pygophore was dissected after treating the last three abdominal segments with hot 10% KOH, the phallic complex was dissected and the parameres and phallus were separated and mounted in polyvinyl lactophenol (PVLP) with lignin pink dye, and photographed. All specimens and slides of genitalia are preserved in Modern College of Arts, Science and Commerce, Shivajinagar, Pune.
Measurements: All measurements (based on one male (MCZH 132, June 2017) and one female (MCZH 131, October 2016) given below are in mm and they are separated as male / female.
Total length 4.5 / 5.125, total length of head 0.625 / 0.625, anteocular length 0.1 / 0.125, postocular length 0.25 / 0.25, head width dorsally at eye 0.5 / 0.5; antenna: length of first segment 1.75 / 1.875, second segment 1 / 1.125, third segment 1 / mutilated, fourth segment 0.375 / mutilated; labium: length of first visible segment 0.3 / 0.275, second visible (globular) segment 0.15 / 0.18, third visible segment 0.2 / 0.18; thorax length 1.125 / 0.8, pronotum length 0.625 / 0.75, width at anterior angles of pronotum 0.45 / 0.375, pronotum widdth at humeral angles 0.675 / 0.625; fore leg: length of coxa 0.625 / 0.75, femur 1.125 / 1.375, tibia 0.8 / 1.05, tarsus with claw 0.25 / 0.25; mid leg: length of coxa 0.2 / 0.2, femur 1.875 / 1.9, tibia 2.45 / 2.5, tarsus with claw 0.125 / 0.15; hind leg: length of coxa 0.25 / 0.25, femur 2.875 / 3, tibia 3.875 / 3.95, tarsus with claw 0.125 / 0.125; length of fore wing: 3.75 / 3.75, maximum width of fore wing 1.125 / 1.125; male pygophore: length measured laterally up to the tip 1.25; length of paramere excluding curved portion 0.625; length of extended phallus 1.65; length of phallobase in extended phallus 0.5; length of articulatory apparatus in extended phallus 0.4.
Heteroptera, Reduviidae, Emesinae, Ploiariolini
Emesopsis nubila Uhler, 1893
Ishikawa & Okajima (2006) have recently given generic diagnosis, synonyms, additional description and illustrations of E. nubila. Synonyms are therefore omitted here.
Diagnosis: The diagnostic characters for E. nubila are, in brief: head and pronotum yellowish-brown with long erect setae, posterior pronotal lobe about twice as long as anterior pronotal lobe, mid and hind legs with long setae, forewing with typical markings, endosoma of male genitalia with a pair of vesica arms only, and vesica arm thickened in basal half and slender in apical half.
Additional description: Small, delicate, thread-legged bug, with very hairy body. Overall color brown to reddish-brown, ventrally partly dark brown; antennae partly dark brown; membrane of fore wing with a few pale brown spots, veins slightly darker; legs with brown annulations (Image 1A,B). Male darker ventrally than female (at least in the examples before us).
Head small, anteocular part much shorter than sub-globose postocular part; eyes comparatively large; pronotum with short and narrow anterior lobe and long and broad posterior lobe (nearly twice as long as anterior lobe), covered with long colorless wooly setae, these setae densest on posterior lobe of pronotum; female slightly more hairy than male (Image 1C,D). Second visible segment of labium swollen, as seen in lateral view (Image 1E). Pronotum completely covering mesonotum; metanotum with vertical spine (Image 1F).
Fore wing showing typical venation, especially reticulate pattern at base, with brownish spots on membrane (Image 1G).
Fore legs with long coxae; femur with anteroventral and posteroventral series of very small spiniform setae; tibia slightly shorter than femur; tarsus two-segmented; brownish annulation visible on coxa, femur and tibia (Image 1H); mid and hind legs long, slender, with brown annulations; long setae covering on all legs.
Pro-, meso- and metasterna reddish-brown; pleural regions slightly darker (Image 1I,J). Prosternum furrowed in median region; mesosternum with smooth and glabrous patch laterally. Abdomen slender and darker in male (Image 2A), and broad, pale yellow brown but darker at base and apex ventrally in female (Image 2B).
Pygophore elongate, laterally slightly compressed, ventrally convex, setose, moderately sclerotized, with arrow like spiny posterosuperior process projecting above parameres (Image 2C-E). Parameres slightly curved, setose (Image 2F,G). Phallotheca moderately sclerotized; articulatory apparatus short but stout, basal plates fused in apical half; conjunctiva membaranous; vesica with paired processes that are broad at base and narrowed distally (Image 2H–J). Female terminalia (stained with eosin) densely covered with setae (Image 2K).
The above-mentioned characters match with those described by earlier workers. To confirm the species further, we compared the images of pygophore and phallus with the figures given by Wygodzinsky (1966), Villiers (1979) and photos given by Ishikawa & Yasunaga (2004), as well as Ishikawa & Okajima (2006).
The checklist of the Indian species of Reduviidae (Ambrose 2006) includes E. nubila and another species, namely Emesopsis bimedia Ravichandran & Livingstone, 1989 from ‘Coimbatore, Tamil Nadu’. This latter species has been never recorded again. Wygodzinsky (1966) studied a specimen of E. nubila from Coimbatore and what has been described as E. bimedia may also be E. nubila. From the description given by the authors (and one line drawing of dorsal habitus in unpublished thesis, Ravichandran 1988), it is difficult to compare E. bimedia and E. nubila; the authors state the difference to be the absence of setae on mid and hind legs and absence of piceous spot near antennae in E. bimedia (Ravichandran & Livingstone 1989). Efforts to collect material in Coimbatore and comparison with actual type (if available) are essential to settle this problem.
We believe this to be the first photographically illustrated documentation and brief description of Emesopsis nubila found in India. After Distant’s original description of Calphurnia reticulata Distant, 1909, currently a junior synonym of E. nubila, there is no subsequent record from India. Lack of extensive surveys and lack of expertise in taxonomy of this subfamily in India are probably the main reasons for the poor state of our knowledge about Emesinae of India.
In a brief two-year survey of Emesinae near Pune, Maharashtra State, we have come across several such bugs which will be the subject of separate papers; Kulkarni & Ghate (2016a) have already reported the presence of Myiophanes greeni Distant (type locality Sri Lanka) from India for the first time. Subsequently, a new emesine species, namely Bagauda ernstmyeri Kulkarni & Ghate, 2016 was also added to the Indian fauna (Kulkarni & Ghate 2016b). This indicates that these small and delicate emesine bugs need more attention as we hardly know about their distribution in India.
Ambrose, D.P. (2006). A checklist of Indian assassin bugs (Insecta: Hemiptera: Reduviidae) with taxonomic status, distribution and diagnostic morphological characteristics. Zoos’ Print Journal 21(9): 2388–2406; http://doi.org/10.11609/JoTT.ZPJ.871.2388-406
Ang, Y., L.J. Wong & R. Meier (2013). Using seemingly unnecessary illustrations to improve the diagnostic usefulness of descriptions in taxonomy - a case study on Perochaeta orientalis (Diptera, Sepsidae). ZooKeys (355): 9.
Distant, W.L. (1910). The Fauna of British India, including Ceylon and Burma. Rhynchota, 5 (Heteroptera: Appendix). Taylor & Francis, London, 174pp.
Ishikawa, T. & T. Yasunaga (2004). The emesine assassin bug genus Emesopsis (Heteroptera: Reduviidae) from Japan. Tijdschrift voor Entomologie 147(2): 221–228.
Ishikawa, T. & S. Okajima (2006). The assassin bug genus Emesopsis (Heteroptera, Reduviidae, Emesinae) in Thailand. Denisia 19, zugleich Kataloge der OÖ. Landesmuseen, Neue Serie 50: 457–474.
Kulkarni, S. & H.V. Ghate (2016a). First record of the thread-legged assassin bug Myiophanes greeni Distant, 1903 (Heteroptera: Reduviidae: Emesinae) from India. Biodiversity Data Journal 10(4): e7949; http://doi.org/10.3897/BDJ.4.e7949
Kulkarni, S. & H.V. Ghate (2016b). A new cavernicolous assassin bug of the genus Bagauda Bergroth (Heteroptera: Reduviidae: Emesinae) from the Western Ghats, India. Zootaxa 4127(2): 365–375.
Ravichandran, G. (1988). Biosystematics and ecophysiology of the non tibiaroliate assassin bugs Heteroptera Reduviidae of southern India. Unpublished PhD Thesis, Bharathiar University, Coimbatore, 422pp.
Ravichandran, G. & D. Livingstone (1989). Two new species of Emesinae from Western Ghats. Journal of Entomological Research 13 (2): 125–127.
Villiers, A. (1979). Faune de Madagascar 49 Insectes Hémiptères Reduviidae (2e partie). C.N.R.S., Paris, 202pp.--
Wygodzinsky, P.W. (1966). A Monograph of the Emesinae (Reduviidae, Hemiptera). Bulletin of the American Museum of Natural History 133: 1–614.