SCIENTIFIC CORRESPONDENCE

First report of the brown widow , geometricus C. L. Koch (Araneae: ) from India

The Theridiids or comb-footed com- and Manora (near Karachi, in ) than females and the female genitalia has prise a large and diverse family. They are were the only two locations in the Indian dumb-bell-shaped seminal receptacles12,15. nocturnal and web-living. Spiders of the subcontinent where L. geometricus was The body measurements of the single Theridiidae family build irregular snares, known to occur. Later Levi12 and Garb adult female of L. geometricus are given from the threads of which they suspend et al.6 too included India in the species in Table 1. The specimen is described as themselves in an inverted position wait- distribution range, citing Pocock10 and follows. Carapace is brown, covered with ing for their prey. They are distinguished Cambridge11. However, the reports of fine hair. Eyes in two distinct rows, both from other spiders by the presence of a Pocock and Cambridge pertain to Paki- slightly recurved. Eyes of anterior lines distinct comb on the tarsus of the fourth stan. No subsequent reports of this spe- subsequently spaced, and the median a pair of legs, consisting of a row of strong cies were found from present-day Indian little larger than laterals. Abdomen is curved and toothed setae, bristles of which territory, including Tikader1 and Siliwal globular, slightly compressed laterally, are longer than those on the dorsal side et al.9. Thus, this report is the first for- light to golden brown. Dorsally, symmet- of tarsus IV, and their labium is not rebor- mal record of occurrence of the species rical markings consisting of dark brown dered1,2. The family is best known due to L. geometricus C. L. Koch, 1841 from spots with brown loop-like markings on the notoriety of its genus Latrodectus, also India3. the sides (Figure 1). Each marking con- called widow spider. L. geometricus has a cosmopolitan dis- The widow spider genus Latrodectus tribution ranging from United States, South Walckenaer, 1805, shows a worldwide America, South , and other parts of Table 1. Body measurement of an adult distribution, occurring across multiple Africa3,12. L. geometricus is considered female Latrodectus geometricus 3 continents and oceanic islands . Several to have been introduced to many parts of Character Measurement (in mm) species of Latrodectus are found across America, and , as it was the world. These include Latrodectus geo- detected relatively recently in each of Total body length 8.6 metricus (brown widow) and L. indisti- these locations and in association with Carapace length 3.1 nctus in Africa, L. mactans (black widow) urban environments. Despite its broad Carapace width 2.7 in the West Indies and North America, L. distributional range, L. geometricus may Abdomen length 5.5 tredecimguttatus (Karakurt or black wolf) be native to parts of Africa, as it appears to Leg I 17.8 in South Europe, L. bishopi (red widow be extremely widespread there, but in Leg II 10.8 Leg III 9.0 spider), L. variolus (northern widow spi- isolated and narrow ranges elsewhere6,12. Leg IV 14.6 der) in the United States and L. hasselti We collected the specimen (single adult (red-back spider) in the Australian conti- female) of L. geometricus on the forest nent, Japan and India4–6. floor. Therefore, details of the spider’s Members of this genus are notorious web structure and microhabitat preference due to the highly potent neurotoxin. The could not be recorded. However, the black widow venom, which contains webbing has been reported to be dirty α-latrotoxin, triggers massive neurotrans- and unkempt, and egg sacs are covered mitter release upon injection in verte- with little pulpules on their outer surface, brates, and is known to form pores in cell often in well-illuminated places13. The membranes7. Latrodectus species are gen- web consists of a small retreat (approx eralist in their predation and are known 1.5 m above the ground) which opens to to feed on a wide array of organisms a dome-shaped sheet that leads down such as insects, crustaceans, other arach- close to the ground. The sheet then turns nids, and on small vertebrates, including into a characteristic cobweb mesh, with lizards and geckos8. This broad diet may gumfoot lines leading to the ground14. in part explain the presence of toxins in We confirmed the genus of our specimen their venom that are known to affect by comparing the following characters vertebrates. Latrodectus species are from Levi12, and Levi and Randolph15. known to have an affinity for disturbed The following diagnostic characters char- habitats Latrodectus6. hasselti is the only re- acterize the genus Latrodectus. Carapace, ported species of the genus Latrodectus normal in form, with clypeus equal in from India so far1,9. In 1900, Pocock10 height to the ocular area, and the lateral reported L. geometricus from what was eyes being widely separated. The cheli- then British India. His specimen was col- cerae are without teeth. Legs are long, lected from only one location: Karachi first pair of legs longer than the fourth

(below 10 m asl), which is now in Pakistan. pair, superior claws are toothed almost to 11 In 1902, Cambridge revised the genus apex, have a large globular abdomen, and Figure 1. Latrodectus geometricus, dorsal Latrodectus, according to which Karachi a large cololus; males are much smaller view.

CURRENT SCIENCE, VOL. 93, NO. 6, 25 SEPTEMBER 2007 775 SCIENTIFIC CORRESPONDENCE sists of a brown centre and a light brown The site is a part of one of the Westerly more venomous and intensity of the bite to yellow periphery that is bordered dark spurs of the Western Ghats, having a may depend on the size of the spider in- brown. Longitudinally, dorsum with 3–4 maximum altitude of about 1300 m and flicting the bite17,19. Though non-aggressive, similar markings in the centre, anterior- an average annual rainfall of 1050 mm. these spiders bite only when handled or most being circular, proceeding ones some- The vegetation in the region is dominated trapped, preferring to retreat most of the what triangular. Spinnerets clustered in a by Tectona grandis, Terminalia crenulata times when simply threatened17. striated ring-like form, slightly on the and Anogeisus latifolia. The valley has In captivity, the spider maintained an ventral side. Distinct bright orange hour- many seasonal streams flowing only dur- inverted position in the container. It glass marking on the ventral surface pre- ing the monsoons, when it harbours rich mostly maintained a constricted position sent (Figure 2 a). Laterally, abdomen shows seasonal herbs. The area has a dry period with its legs pulled inwards, and spun a loop-like markings extending towards the length of seven to eight months. The vege- few irregular strands on the lower sur- hourglass markings (Figure 2 b). All legs tation is degraded, secondary deciduous face of the lid that extended down up to faint, with patella and tip of their tibia type, with planted teak and poor under- the inner walls of the container. Cock- darker. growth. The forest composition consisted roaches of Blatella sp., measuring 1 cm in Epigynum with lower lip projecting on mainly of fire-resistant species, with length, were placed as food in the con- the sides beyond the upper lip of the mature trees observed rarely. Grazing tainer. The spider preferred to eat in pri- opening. Spermathecae paired, copulatory and human settlements were observed, vacy. The intact remains of the cockroach’s ducts coiled (Figure 2 c). The species-level with agriculture at the periphery. exoskeleton were always observed after identity of the specimen was established Compared to other Latrodectus species feeding. The spider was often seen put- by comparing its genital structure to that like the American black widow spiders, ting her first pair of legs near her fangs, described by Levi12, and Levy and Amitai16. whose envenomation is often referred to especially before feeding and when ag- D. B. Bastawade (Zoological Survey of as ‘latrodectism’, similar effects are less gravated. India, Pune) confirmed the species identity. common from L. geometricus bites17. L. geometricus is among those spiders The spider was collected by S.S. in a However, according to a study in South that have been reported from Pakistan, patch of deciduous forest (18°22′N, Africa, L. geometricus bites in humans but have not yet been reported from India. 73°46′E), at an elevation of 800 m amsl, cause localized pain and cramps with The distribution of many species from approximately 20 km southwest of Pune profuse sweating and increased blood Pakistan may extend up to India9. Further city on 29 August 2004 in the afternoon. pressure18. In addition, females may be studies are needed to discover such spe-

Figure 2. Identification characters of L. geometricus. a, Ventral view of abdomen of L. geomet- ricus showing orange hourglass marking. b, Lateral view. c, Dorsal view of spermathecae.

776 CURRENT SCIENCE, VOL. 93, NO. 6, 25 SEPTEMBER 2007 SCIENTIFIC CORRESPONDENCE cies. Also, further studies are needed to 7. Orlova, E. V. et al., Nature Struct. Biol., ACKNOWLEDGEMENTS. We thank Dr D. B. explore the spider diversity of the West- 2000, 7, 48–53. Bastawade, for critically reading the manu- ern Ghats and other parts of India. Since 8. Hódar, J. A. and Sánchez-3LHUR ) J. script and helping with microscopic prepara- this spider species has medical signi- Zool. (London), 2002, 257, 101–109. tions and observations; Prof. Herbert Levi for 9. Siliwal, M., Molur, S. and Biswas, B. K., ficance, a study on the effect of spider comments and Prof. R. Gadagkar, IISc, Ban- Zoos’ Print J., 2005, 20, 1999–2049. galore for support and guidance, Mr Milind bites and their antidote, pertaining to the 10. Pocock, R. I., Fauna of British India, Kolatkar for figures. We also thank Dr Shonil Indian context is necessary. Arachnida, Taylor and Francis, London, Bhagwat and Mr Neelesh Dahanukar and Dr 1900, pp. 237–238. Thresi for help, and Dr M. G. Watve for en- 11. Cambridge, F. O. P., Proc. Zool. Soc. couragement and support. London, 1902, 1, 247–261. 1. Tikader, B. K., Handbook of Indian Spi- 12. Levi, H. W., Trans. Am. Microsc. Soc., ders, Zoological Survey of India, Cal- 1959, 78, 7–43. Received 13 March 2006; revised accepted cutta, 1987, pp. 210–213. 13. McCrone, J. D. and Stone, K. J., Arthro- 24 July 2007 2. Kaston, B. J., How to Know the Spiders, pods Fla. Neighboring Land Areas, 1965, W.M.C. Brown Company Publishers, Du- 2, 5–9. 1, buque, 1972, pp. 97–98. 14. Agnarsson, I., Zool. J. Linn. Soc., 2004, SHANTANU SHUKLA * 2 3. Platnick, N. I., The world spider catalog, 141, 447–626. VIVEK GOUR BROOME version 7.5. American Museum of Natural 15. Levi, H. W. and Randolph, D. E., J. History, 2007; http://research.amnh.org/ Arachnol., 1975, 3, 31–51. 1Centre for Ecological Sciences, entomology/spiders/catalog/index.html. 16. Levy, G. and Amitai, P., Zool. J. Linn. Indian Institute of Science, 4. Daniel, J. C. and Soman, P. W., J. Bom- Soc., 1983, 77, 39–63. Bangalore 560 012, India bay Nat. Hist. Soc., 1961, 58, 823–826. 17. Diaz, J. H., Am. J. Trop. Med. Hyg., 2J.E. Farm, Marunji PO, 5. Siliwal, M. and Kumar Dolly, Curr. Sci., 2004, 71, 239–250. 2001, 81, 1170–1171. 18. Muller, G. J., S. Afr. Med. J., 1993, 83, Mulshi Taluka, 6. Garb, J. E., Gonzalez, A. and Gillespie, 399–405. Pune 411 057, India R. G., Mol. Phylogenet. Evol., 2004, 31, 19. Timms, P. K. and Gibbons, R. B., West *For correspondence. 1127–1142. J. Med., 1986, 144, 315–317. e-mail: [email protected]

CURRENT SCIENCE, VOL. 93, NO. 6, 25 SEPTEMBER 2007 777