First records of four species of webspinners ( Insecta : Embioptera ) from Chhattisgarh , India

The present paper deals with the first taxonomic account on webspinners (Embioptera) of Chhattisgarh, India. Out of 32 species or subspecies known from India, four species, namely Oligotoma humbertiana (Saussure, 1896), Oligotoma saundersii (Westwood, 1837) and Oligotoma annandalei Kapur & Kripalani, 1957 (family Oligotomidae) and Pseudembia setosa Ross, 1950 (family Embiidae) are reported for the first time from Chhattisgarh. DOI: 10.15560/10.6.1565 N o t e s o N G e o G r a p h ic D is t r ib u t io N

In connection with the project "Faunal Diversity of Protected Areas of Chhattisgarh", field surveys were conducted from June 2011 to August 2012. During the surveys, embioptera specimens were collected from different localities in Chhattisgarh (Figure 3). Most of the winged male specimens were collected in a light trap by using a high-power mercury lamp (2700 lumen). Some specimens were collected by swiping a butterfly net over leaf litter. All specimens were placed in 70% Ethanol. Specimens were examined first under a stereoscopic binocular microscope and the body form, dimensions, colour and other characteristics noted. For further study, specimens were treated with 10% KOH for varying lengths of time depending upon the sclerotization, and then cleared in distilled water. After the usual dehydration by up-gradation of alcohol, specimens were kept in clove oil and temporary slides were prepared with clove oil or alcohol. Identification of the specimens was done using keys by Kapur & Kripalani (1957) and Ross (1950). Identified specimens were deposited in National Zoological Collections, ZSI, Kolkata, India.
Photographs were taken with a Leica Stereo Zoom Microscope (Leica M205A) using the Leica Application Suit software (LAS V3.8).

Family Oligotomidae Genus Oligotoma Westwood, 1837
Oligotoma humbertiana (Saussure, 1896) ( Figure 1A) Diagnostic characters: Process of left hemitergite (10LP) small, very narrow, its apex abruptly hooked to the left and minutely bifurcated [Figure2A.i]. The spine of the Among the small insect orders, Embioptera is a distinct, monophyletic group with representatives distributed throughout warmer regions of the world (Miller et al. 2012). Less than 400 valid species of this group are currently recorded but there are as many as undocumented species (Miller 2009).
Webspinners are medium sized (5 to 25 mm) insects with a slender and campodeiform body. Mouth parts are prognathus and of the chewing type. Antennae are filiform. Protarsomere I or the foreleg basitarsi possesses a multinucleated silk gland that is responsible for these insects' ability to spin silk (Mukerji 1927). The insects make nests by spinning web tunnels over dry leaves, under barks and stones. These nests serve as protection from predators or parasites, for regulating the humidity, and for laying eggs. Males are generally winged but females are apterous (Ross 2000;Edgerly et al. 2002).
The work on Indian Embioptera is limited. The first record of this group from India was made by Imms (1913) who described from the Himalayas Embia major Imms, 1913, which was later synonymised with Parembia valida (Hagen, 1885). Another species, Embia minor Mukerji, 1927 was described from Kolkata with a brief note on its biology (Mukerji 1927). Pseudembia paradoxa Davis, 1939 and Pseudembia truncata Davis, 1939 were described from Bihar and Karnataka respectively (Davis 1939). Metembia flava Ross, 1943 and Oligotoma falcis Ross, 1943 were described from South India (Ross 1943). Later, Ross (1950) listed twelve species of Embioptera from India. Some species were also studied by Ananthakrishnan and Ananthasubramanian (1956) from South India. Kapoor and Kripalani (1957) studied fifteen species with six new species of the family Oligotomidae from India. Two species, Oligotoma dharwariana Bradoo, 1971 and Aposthonia josephi Bradoo, 1971 were described from Karnataka by Bradoo (1971). Chandra (1999) reported two species of Embioptera from South Andaman and Barren Islands in Andaman and Nicobar Islands. Recently, Ross (2007)  Abstract: The present paper deals with the first taxonomic account on webspinners (Embioptera) of Chhattisgarh, India. Out of 32 species or subspecies known from India, four species, namely Oligotoma humbertiana (Saussure, 1896), Oligotoma saundersii (Westwood, 1837) and Oligotoma annandalei Kapur & Kripalani, 1957 (family Oligotomidae) and Pseudembia setosa Ross, 1950 (family Embiidae) are reported for the first time from Chhattisgarh. Oligotoma saundersii (Westwood, 1837) ( Figure 1B) Diagnostic characters: Process of right hemitergite (10RP 1 ) without a sub-apical spine, 10LP broad spatulate, with curved sides. Left circus basipodite (LCB) well developed, curved outwards, ending obtusely. LPPT spine broad, sickle shaped. A slender, heavily chitinized spine arises sub-terminally from the margin of the ninth sternite, with two minute teeth at its base and the spine curves to the right under the end of the sternite projecting upwards and backwards terminally ( Figure 2C-D).  Kapur & Kripalani, 1957 [Figure 1C] Diagnostic characters: 10LP elongated slightly constricted at the base, rather club-shaped with rounded apex and bearing two well separated spines on the left side [Figure1E.i]. Ninth sternite (H) broad basally but gradually narrowed towards the left cercus to a process (HP) bearing a number of short, conical spines [ Figure 1F]. Distinct LPPT is present and broad, hooked inwards and upwards terminally and acutely pointed beneath HP [ Figure 1E]. Remark: Description of the holotype male indicates the body color of this brown with some parts darker, but the collected specimens were dark black-brown throughout the body.

Oligotoma annandalei
Family Embiidae Genus Pseudembia Davis, 1939 Pseudembia setosa Ross, 1950 (Figure 1D) Diagnostic characters: Hind basitarsi elongate, densely setose with two bare bladders. Medial flap of right hemitergite, small, sub-dorsal, bearing a very dense cluster of long caudally directed setae, the basal sockets of which is so close that they touch one another at the apices ( Figure 2E-F   Among the 32 species or subspecies of Embioptera reported from India, four species included in the present paper are recorded for the first time from Chhattisgarh. Of these four species, two are endemic Indian species (Oligotoma annandalei and Pseudembia setosa), earlier recorded from Orissa and Tamil Nadu respectively. The other two species are widely distributed in India and other countries. Most of the specimens were winged male and collected using a light trap. The ability of embiopterans to run backwards very fast was a remarkable behaviour that was observed in the field. It is clear that further taxonomic and ecological study of embiopteran insects from Chhattisgarh, India may reveal more species and additional interesting information about their habit and habitats.