Introduction

The Blepharida-group of genera consists of robust and brightly colored flea beetles (Figs 1–10). Furth (1998) lists 16 genera in the Blepharida-group, which are united by characters of the eye shape, metatibial, aedeagal, and spermathecal morphology. Medvedev (1999) added three new genera, Asiophrida Medvedev, Blepharella Medvedev, and Furthia Medvedev from the Oriental region, making 19 genera in total. The Blepharida-group has a primarily Old World tropical distribution, with the exception of Euplectroscelis Crotch being endemic to Mexico (Furth 1992; Furth and Lee 2000). We follow Furth and Lee (2000: 27, Table 1) on the composition of the Blepharida-group genera as this is the most recent discussion of these genera, building from his morphological and classificatory discussions (Furth 1992, 1998) and pointing out the limitations of catalogue phylogenies. A modern phylogenetic analysis of relationships among these taxa and with other flea beetles is badly needed.

Species in the Blepharida-group are documented most commonly on host plants in the Anacardiaceae, Bignoniaceae, Burseraceae, and Sapindaceae (Table 1). However, there are several single species records from Apocynaceae, Caesalpiniaceae, Elaeocarpaceae, Fabaceae, Lythraceae, Meliaceae, Moraceae, and Verbenaceae, which raise interesting questions about diet evolution as well as the distinct possibility of questionable host reports. Additionally, Furth (1998) indicated how the lack of reference sources in Jolivet and Hawkeswood (1995) could mislead about true chrysomelid-plant associations. Host chemistry may likely have played an important role in the co-evolution of Blepharida Chevrolat (73 species; Figs 2–3) with their hosts in Bursera Jacq. ex L. (Burseraceae) (Becerra 1997, 2003, 2004a, b, 2007; Becerra and Venable 1999; Becerra et al. 2001). Host acquired secondary metabolites also appear to contribute to the effectiveness of an unusual larval fecal defense in Blepharida (Morton 1997; Morton and Vencl 1998; Vencl and Morton 1998, 1999).

Furth and Lee (2000) provided a morphological synthesis of the Blepharida-group, and reported that morphological data for immature stages were available for only nine species in Blepharida Chevrolat, Diamphidia Gerstaecker, Euplectroscelis Crotch, Ophrida Chapuis, and Podontia Dalman. Within this broader group, Takizawa (2005) recognized a Podontia-genus group comprised of Blepharida (Figs 2–3), Ophrida (Fig. 6), and Podontia (Figs 7–9), based on larval setal patterns and deposition of eggs in rows. Chaboo et al. (2007) added data for three more species in the southern African genera Diamphidia and Polyclada Chevrolat and Lee and Cheng (2007) added data for two Taiwanese species—Ophrida spectabilis (Baly) and Podontia lutea (Olivier) (Figs 6 and 8 respectively).

In Blepharida, Diamphidia, Podontia, and Polyclada, larvae retain their feces directly on the dorsum. This coating acts as a deterrent to attacking enemies such as ants (Vencl and Morton 1998, 1999). The fecal coat may also serve to moderate body temperature or to reduce water loss but the functions have not been tested. Fecal retention and the dorsally-positioned anus represent complex characters supporting the monophyly of the Blepharida-group (Paterson 1943).

The genus Podontia Dalman 1824 (Figs 7–9) comprises 14 Asian species ranging from Indonesia to Indo-China, with one species occurring in northern Australia (Baly 1865; Heikertinger and Csiki 1940). Podontia adults are distinguished from other Blepharida-group species by bifurcate prosternum, saddle-shaped mesosternum and strongly inwardly curved bifid tarsal claws (Medvedev 1999; Becerra 2004a). Podontia larvae vary in the presence and shapes of meso and metathoracic tubercles (Kimoto and Takizawa 1997). Immature stages are known for only Podontia affinis (Gröndal) (Fig. 7; Takizawa 1978; Furth and Lee 2000), Podontia dalmani Baly (Furth and Lee 2000), and Podontia lutea (Olivier) (Fig. 8; Takizawa 1978; Jolivet and Hawkeswood 1995; Kimoto and Takizawa 1997; Lee 1999; Furth and Lee 2000). With adults at ~2 cm long, Podontia lutea, the golden leaf beetle, is reputedly the largest flea beetle in the world (Fig. 8; Furth 1999).

Here, we review the biology of Podontia and other Blepharida-group genera and provide the first natural history account of Podontia congregata Baly, 1865. An endemic to the southern Western Ghats and adjoining areas, Podontia congregata is the largest flea beetle in southern India, ranging from 11.5 to 14.7 mm in length. Our study is based on both field and laboratory observations.

Natural History of Podontia Dalman, 1824

The biology for most Podontia species is unknown; however, host data on Podontia affinis, Podontia lutea, and Podontia quatuordecimpunctata (Linnaeus) indicate that these species severely defoliate anacardiaceous trees. For example, Podontia affinis (kedongdong spring-beetle) ranges from Indonesia to China and is a pest in Indonesia, where its larvae attack the foliage of Spondias dulcis Forster (Anacardiaceae; =Spondias cytherea Sonn., ambarella or kedongdong tree; Daulmerie 1994; Morton 1987). Female Podontia affinis live about 3 months, lay loose groups of eggs on the undersides of leaves and coat them with some substance (Kalshoven 1951). The larvae are parasitised by an encyrtid wasp, Ooencyrtus podontiae (Gahan) (Table 2; Gahan 1922; Kalshoven 1951).

The golden leaf beetle, Podontia lutea is large sized (~2 cm, Fig. 8) and its attractive coloration promotes its use in cheap Lucite jewelry. The limited available data indicates biology like other Blepharida-group members (Hsu 1934a, b; Lee 1999; Furth and Lee 2000). This beetle is a pest of the anacardiaceous shrub, Toxicodendron vernicifluum (Stokes) F. Barkley (=Rhus verniciflua Stokes) which is the source of the lacquer used in Asian furniture manufacturing (Li and Wang 1984a, b). The coccinellid beetle, Aiolocaria mirabilis (Motschulsky), has been studied as a biocontrol agent (Li and Wang 1984a, b).

Podontia quatuordecimpunctata is the best-known Podontia species because both adults and larvae defoliate the tree Spondias dulcis. This tree, commonly known as the mak-ok, hog plum, or golden apple tree, is cultivated for its edible fruits in Indonesia, Malaysia, India, Thailand, and the Caribbean (Figs 11–15; Table 1 and references therein). Pramanik and Basu (1973) first described the Podontia quatuordecimpunctata life cycle (See also Singh and Misra 1989). Like Podontia affinis, this species' pest status has led to the use of a vernacular name, “kadondong beetle"(alternate spelling “kedongdong”; Corbett and Yusope 1921), which resembles that for Podontia affinis (Morton 1987). The colorful orange-pink adults are active from June to October, and form pairs that copulate multiple times (Fig. 12). [Additional images of live stages can be viewed at: http://greeneyesth.multiply.com/photos/album/33/Podontia_quatuordecimpunctata]. Females oviposit 20–60 eggs in clusters on the leaf surface; eggs are bright yellow, naked and are arranged in multiple layers, usually two. Hatching occurs within 7–8 days and the yellow-brown larval instars feed gregariously and prefer younger leaves (Singh and Misra 1989). Barlow (1900) indicated that all five larval stages retain a fecal coat (Figs 13–14), possibly mimicing bird droppings (Barlow 1900; Stebbing 1914; Baksha 1997). The final instar descends the plant, enters the soil, and forms an earthen cell in which it pupates. The yellow-brown pupae last 14–29 days. Adults hibernate in soil or under leaves. Insect (e.g., Fig. 15), nematode, and fungal enemies are documented (Table 2; Singh and Misra 1989). Foliar sprays of cypermethrin (Baksha 1997), metathion (Sardar and Mondal 1983), and carbaryl (Singh and Misra 1989) have been recommended as effective controls.

Natural history of other Blepharida-group genera

Asiophrida Medvedev comprises 20 species in three subgenera (Medvedev 1999; Zhang and Yang 2008; Mohammedsaid 2004). One of us (KDP) recently discovered populations of Asiophrida marmorea (Wiedemann) on one known host, Garuga pinnata Roxb. (Burseraceae; Table 1) at Vellanikkara, Kerala, southern India (Fig. 1). Larvae are naked, not retaining fecal coverings; field study is underway.

The biology of Blepharida, with 55 species, is currently the best known among Blepharida-group genera. Life cycle data have been published for Blepharida rhois (Forster) (as Blepharida dorothea Mignot) (Frost 1972). Blepharida evanida (Baly) is reported as a source of arrow poison used by Kalahari San Bushmen (Lewin 1912, 1923). Furth (1982, 1985) summarized the biology of Blepharida sacra (Weise), the sacred sumac flea beetle. Generally, Blepharida adults lay clusters of eggs on branches and cover them with fecal material. The slug-like larvae retain soft feces, or long fecal threads or pellets under drier conditions. The prepupal and pupal phases are underground in earthen cells and can last over 7 months. Eggs are parasitized by the eulophid wasp, Tetrastichus sp., while larvae are attacked by the fly parasitoid, Meigenia mutabilis Fallen (Diptera: Tachninidae; Furth 1985).

Crimissa cruralis Stål, the red cashew beetle, is a major pest of cultivated cashew in Brazil, Anacardium occidentale L. (Fig. 4; Pereira et al. 1975; Bastos 1975, 1977a; Bastos and Vieira 1977a, b; Bastos et al. 1979). Eggs are deposited on the trees, larvae eat from leaves, and adults rasp and leave characteristic lesions on leaf surfaces (Pereira et al. 1975). Pupation is underground in soil-based cocoons near the base of the trunk (Santos 1972; Bastos 1977b; Santos and Vieira 1977; Sales and Pereira 1978). Morphology of the immature stages is apparently undescribed. Various chemicals (Bastos 1975; Bastos and Veira 1977a, b; Bastos et al. 1979) and cashew gum exudates (Marques et al. 1992) have been tested to control this pest.

The nine known species of Diamphidia are distributed along the eastern coast from Ethiopia to South Africa and into Namibia (Fig. 5; Baly 1865; Heikertinger and Csiki 1940). Several species of Diamphidia are implicated as sources of the Kalahari San arrow poison (Lewin 1923; Roodt 1993; Neuwinger 1996). Diamphidia biology is similar to that of other Blepharida-group members with the exception that most species have woody hosts in Burseraceae (Commiphora Jacq.) or Anacardiaceae (Sclerocarya Hochst.) (Table 1; Chaboo et al. 2007).

The austral-oriental genus Ophrida Chapuis consists of four or five species (Medvedev 1999; Zhang and Yang 2008). Immature biology is known for Ophrida scaphoides (Baly) (Kimoto and Takizawa 1997), Ophrida spectabilis (Baly) (Bilun 1998a; Park and Lee 2001; Lee and Cheng 2007), and Ophrida xanthospilota (Baly) (Bai and Zhang 1990; Zhang and Yang 2008). There appears to be one generation per year, with eggs overwintering in slits of host twigs (Park and Lee 2001) or on host trunks (Bilun 1998a, b). The three larval instars are gregarious and retain fecal coverings. Mature larvae descend the plant and construct earthen cocoons underground, at about 20 cm deep; pupation takes about two months (Bilun 1998a). Ophrida spectabilis specializes on Rhus Linnaeus (Park and Lee 2001) and is a pest of Rhus chinensis Mill. (Bilun 1998a; Yang et al. 1997) and Rhus punjabensis J. L. Stewart (Wang et al. 1998). Rhus chinensis, or Chinese sumac, is the source of gallnuts (or nutgalls); these “nuts"are extruded tannins that harden and are used in traditional Chinese medicine (Bilun 1998a, b). The plant's medical value has led to the development of chemical and biocontrol measures that include egg and larval removal from the host (Bilun 1998b), powder applications containing Beauveria bassiana (Bals.-Criv.) Vuill. (Fungi: Clavicipitaceae) (Yang et al. 1997; Wu et al. 1999), and propagation of an egg-parasitoid wasp, Trichogramma Westwood (Hymenoptera: Trichogrammatidae; Yang et al. 1997; Bilun 1998a, b; Wang et al. 1998). In China, Ophrida xanthospilota is a pest of the anacard Cotinus coggygria Scop. (Bai and Zhang 1990).

The 12 species of Polyclada Chevrolat are distributed along east Africa, from South Africa to the Arabian Peninsula (Heikertinger and Csiki 1940; Bryant 1942; Chaboo in review). Oddly, some species are also reported from Senegal, which suggests a wider distribution of species, misidentifications, or possibly an inaccurate application of generic concepts. So far as is known, all larvae retain feces (Chaboo et al. 2007). Late 4th instar larvae of some species are dug up, crushed, and their hemolymph is applied to hunting arrows by the San (Bushmen) in Namibia and Botswana (Neuwinger and Scherer 1976; Roodt 1993; Chaboo et al. 2007; Chaboo 2011).

The South American genus Procalus Clark comprises nine species that are associated with Anacardiaceae (Table 1; Jerez 1992, 1995, 1999). Two species are significant defoliators of economically important plants in the sub-Andean “matorral"habitat (Mediterranean shrubland) (Fuentes et al. 1987). In Hawaii, Podontia mutans (Blanchard) was introduced as a biocontrol agent for Christmas berry, the weed Schinus terebinthifolius Raddi (Anacardiaceae) (Krauss 1962, 1963). Viviane Jerez has described the biology of Podontia artigasi Jerez (Jerez 2003), Podontia mutans (Jerez 1999, 2003), Podontia ortizi Jerez (Jerez 2003), Podontia reduplicatus Bechyné (Jerez 2003), Podontia viridis (Philippi and Philippi) (Jerez 1985, 1988), and Podontia silvai Jerez (Jerez 1995, 2003). Adults become active in early spring; by late spring (October) the females attach groups of cylindrical eggs to leaves and cover them with a secretion. The life cycle includes three larval instars. Third instar larvae construct underground cocoons of sand grains and overwinter for up to nine months. Cocoons are found about 3 cm underground at the base of the host plant. Larvae of Podontia viridis and Podontia mutans retain fecal shields (Jerez 1985, 1999). Mermithid nematodes are known to be larval parasites (Jerez and Centella 1996).

Immature stages of Euplectroscelis Crotch, Furthia Medvedev, Neoblepharella (Medvedev) [=Blepharella Medvedev, which was previously occupied as a genus of tachinid flies (Özdikmen 2008)], and Notozona Chevrolat are unknown (Medvedev 1999).

Materials and Methods

One of us (KDP) studied natural populations of Podontia congregata on its host tree, Garcinia gummi-gutta, under field conditions during several visits in 2008–2010 in Vallamkulam, Pathanamthitta, Kerala, India. We also reared beetles in cages for laboratory observations. We examined beetle specimens obtained from the Department of Entomology, College of Horticulture, Mudigere, India (see Fig. 16).

Cage-reared beetle populations were maintained under ambient conditions at Vellayani, Trivandrum, Kerala, India. Individuals from these cage-reared populations were introduced onto field plants of the host for observations. Although Podontia congregata is absent in Vellayani, the host tree grows naturally on the banks of Vellayani Lake.

Habitat 1. India: Kerala State: Pathanamthitta District, Vallamkulum (76°36'18.4"E, 9°22'29.5"N; 12 - 20 m above msl). This is a typical urbanized village in Kerala, where the majority of the agricultural holdings are below 0.5 ha. Homestead farming, a hallmark of the settlement pattern in Kerala, comprises a diverse assortment of crop trees (e.g., Garcinia gummi-gutta), shrubs and herbs, which enhances biodiversity conservation in this densely populated village. This rather hot and humid locality is endowed with a few rivulets to the extent that rice fields can remain submerged during the rainy season. Mature Garcinia gummi-gutta trees are common on the banks of paddy fields and rivulets.

Habitat 2. India: Kerala State: Trivandrum District, Vellayani (76°59'8.3"E, 8°25'47.5"N; 18 m above msl). This is a watershed bordered by small hillocks that drain into Vellayani Lake, which is the second largest freshwater lake in Kerala. Banana and vegetable cultivation dominate the low-lying paddy fields, while a coconut-based cropping system is practiced on the hillocks. Perhaps because it is not preferred for culinary purposes in southern Kerala, Garcinia gummi-gutta is generally uncommon in southern Kerala homesteads and particularly so in Trivandrum. A local preference for dried tamarind fruit (Fabaceae: Tamarindus indica Linnaeus) may explain the low abundance of the host plant here.

Habitat 3. India: Kerala State: Alappuzha District: Pandanad (76°35'0.7"E, 9°19'15.1"N; 12 m above msl), located ~8 km south of Vallamkulam. This is an urbanized village similar to Habitat 1.

Habitat 4. India: Kerala State: Trivandrum District: Ponmudi (77°06'43.7"E, 8°45' 19.9"N; 872 m above msl), a hill station, near the southern end of the Western Ghats mountains. A century ago Ponmudi was covered with pristine wet ever green forests and is a hot spot of biodiversity in peninsular India. However, agricultural plantations, tourism, and commercial tree felling has altered the landscape significantly.

Laboratory conditions. Laboratory culture of Podontia congregata was started at Vellayani from nearly half a dozen adults and several larvae collected at Vallamkulam. Adults were confined in a cage of 30 cm3. We offered food and oviposition sites by supplying branches of the host plant, with the cut end placed in water in a glass bottle. Leaves with eggs were transferred to Petri dishes. Larvae were reared on branches in cages or plastic containers, as well as in Petri dishes. Wet soil was provided for pupation. Rearing was carried out at an ambient temperature of about 22–32°C. About two dozen laboratory reared adults and larvae were introduced onto a naturally growing Garcinia gummi-gutta tree at Vellayani during October–December, 2008, and the different life stages were observed.

Natural history of the host plant. Garcinia gummi-gutta (Figs 17–19) grows well in the high rainfall areas of the southern Western Ghats Mountains, India. This medium-sized tree (Fig. 17), locally known as kodampuli, is found naturally along banks of rivers, lakes and inundated paddy fields, and is common in Kerala's homestead gardens, as the fruits (Fig. 19) are used in various ways (Manomohandas et al. 2001). The rind is sun-dried for 3–5 days and smoked, and is used as a prized condiment, for curing fish, and as medicine for humans and cattle (Gupta 2002). The acidic pulp covering the seeds is also edible. The thick fleshy rind of ripe fruits is a rich source of hydroxy citric acid (HCA); its derivatives are unique metabolic regulators of obesity (George 2005). Other uses include coagulating rubber latex and polishing gold and silver (Manomohandas et al. 2001). The wood is used as firewood but not valued as timber (Verghese 1991; Geetha 1994; Manomohandas et al. 2001). The tree yields a translucent yellow resin, which does not form an emulsion with water. It is soluble in turpentine and gives a yellow varnish (Sastri 1956).

Study of fecal coat formation. Nine laboratory-reared second and third instar larvae were washed under a very light stream of tap water and lightly brushed with a soft camel-hair brush to remove the fecal cover. Larvae thus cleaned were observed for the formation of a new fecal cover. The fecal thread was removed from the live animal and immersed in water on a slide for microscopic examination.

Tables 1 and 2. For host plants of the Blepharida-group taxa (Table 1) we incorporated many little-known articles from Indian journals and assembled host records from an extensive primary literature to collate a list that could be most valuable to the widest community of users. We assembled data on enemies for Podontia only, to aid agriculturists dealing with the defoliating effects of these species in Asia. We suspect that there may be obscure agricultural records for other Blepharida-group taxa where they are pests (e.g., Crimissa is a pest of cashew in Brazil) but such a literature survey will need collaborators involved at the local level.

Specimens. The identity of Podontia congregata was determined by examining the holotype deposited in the Natural History Museum, London, UK, with four labels: Type HT, Baly coll., Podontia congregata Baly, examined K. Prathapan, 2005. Specimen vouchers of our study are deposited in the Travancore Insect Collection, Kerala Agricultural University, Vellayani, India, and in the Snow Entomology Collection (SEMC), University of Kansas, Lawrence, U.S.A. (Voucher codes IMcsc00385–IMcsc00390). Vouchers of the bug predator, Eucanthecona parva (Distant) (Heteroptera: Pentatomidae), are deposited in the University of Agricultural Sciences, Bangalore, India, and in SEMC. Vouchers of Ooencyrtus are deposited in the Aligarh Muslim University, India, and in SEMC. Plant vouchers are deposited in the Calicut University Herbarium, Calicut, India (Accession no. 6394).

Results

Eggs of Podontia congregata are deposited in masses (Fig. 20), usually laid in two layers at Vellayani, egg masses were observed in the field on both abaxial and adaxial surfaces of leaves. In the laboratory, the egg masses comprise 4–20 eggs, and were attached mostly on the adaxial surface. Each orange-yellow egg is oriented vertically. Eggs measure 1.82–1.92 mm long and 0.94–1.03 mm wide. About 6–7 days after oviposition, the egg coloration changes to grey brown just before hatching.

The neonate larva (Fig. 21) is lemon yellow with a dark head. Young larvae feed by scraping on the adaxial surface of the lamina (Fig. 21). Older larvae feed by cutting the leaf lamina while positioning themselves on the abaxial side of the leaf. Older larvae were observed singly on leaves, indicating a solitary nature (Figs 22–24). Larvae that are old enough to cut the leaf tend to remain on the abaxial side of the leaf. The larva with its fecal coat resembles bird droppings (Figs 22–23). The larval period varied from 18–25 days.

The larval fecal coat is formed with feces being excreted as a single thread, which is then transversely folded over the back to cover the dorsum of each larva (Fig. 25). Convulsive movements of the dorsum move it forward. The fecal thread is extruded with a glue-like, transparent material that binds the particles together (Fig. 25). When the fecal coats were removed, larvae took about 6–8.5 hours to refurbish a new coat. The coat color depends on the maturity of the leaf eaten by the larva; larvae feeding on tender leaves have a light colored, wet fecal cover, while those feeding on mature leaves have a rather dark green, apparently drier fecal coat.

Formation of pupae (Figs 27–29) was observed in the laboratory. Full fed final instar larvae shed the fecal coat and remained motionless for about 1–2 days and then assumed a C-shape with concave venter. Prior to pupation, they wriggle on wet soil that was provided in the rearing cage, creating a small depression on the surface and then gathering soil particles from around the body and manipulating these with the legs and mouthparts to form a layer covering the body. Ultimately this layer becomes an earthen cocoon roughly globular in shape (Figs 27–28). The larva never dug into soil, but always constructed the cocoon on the surface.

The adult emerged through a nearly circular exit hole. Construction of the cocoon to adult emergence took 21–24 days. The total life cycle was completed in 49–53 days. Adults (Fig. 30) lived in captivity for about 3–4 months. They feed by cutting the leaf lamina. Adults feign death and fall down (= thanatosis) or reluctantly jump when disturbed. Laboratory-reared adults released on naturally growing host plants at Vellayani were found to be less mobile. Some adults remained on the same branch for weeks and oviposited. The color pattern of adults appears to mimic bird droppings. Like larvae, adults too preferred to remain on the abaxial side of leaves.

At Vallamkulam, the insect was active throughout the year except during the dry summer months. Adult and larval presence was noticed after the onset of monsoon rains in May-June in 2008, and larvae were observed until early January 2009. Neither larvae nor adults were observed during the harsh, dry, summer months. Vellayani received the first summer rain of 9.8 mm on 13 March in 2009, and a single newly emerged adult was noticed on 15 March in the field. Two third instar larvae were observed on 11 April indicating sustenance and possible establishment of Podontia congregata at Vellayani where it was newly introduced. Six adults and several larvae were noticed on this tree during the last week of May, 2009. Two adults and three final instar larvae could be spotted after thorough checking of 14 host trees on 14 April at two spots in Vallamkulam. This indicates a similar seasonality and pre-monsoon buildup of the population in both the localities. Interestingly, the introduced Podontia congregata at Vellayani was confined to the single tree on which it was introduced, till the last quarter of 2009. There are 11 other host trees in its vicinity, with the nearest one at a distance of 19 m. Grown-up larvae were observed during December, 2009 on a second tree about 22 m away from the tree on which the beetle was first introduced. This indicates extremely slow dispersal of the insect.

At Vellayani, in 2010, the host trees put forth new flushes during the harsh summer, and all stages of the insect were active throughout the summer, without a break in activity. Diapause in Podontia congregata is probably correlated with flushing of the host tree rather than the harsh dry summer. However, the entire population mysteriously disappeared in May, indicating a probable local extinction of the species.

Nymphs of a pentatomid, Eucanthecona parva (Distant) (Heteroptera), were observed feeding on the larvae of Podontia congregata. A parasitoid was reared from the beetle eggs at Vellayani and is described as a new species, Ooencyrtus keralensis Hayat and Prathapan (Hymenoptera: Encyrtidae; Hayat and Prathapan 2010).

Discussion

The occurrence of Podontia congregata at Vallamkulam and Pandanad extends its range beyond the Western Ghats Mountains to the southwest plains. The absence of Podontia congregata at Vellayani in Trivandrum District, in spite of the presence of the host plant, is curious. Vellayani is only at a linear distance of about 37 km away from Ponmudi, the nearest locality where Podontia congregata was collected. There is no significant difference in altitude, vegetation, or climate between Vellayani and Pandanad or Vallamkulam, except that the rainfall is low at Vellayani (average annual rainfall of about 1833 mm) compared to Vallamkulam (average annual rainfall recorded at Thiruvalla, about 4 km north of Vallamkulam, is 2912 mm) (M. C. Kiran, pers. comm.). Low rainfall, low abundance of the host plant population, competition or poor rate of dispersal could probably explain its past absence in Vellayani.

Members of the Blepharida-group have been reported on many plant families (Table 1), but some records are questionable as they are singleton reports lacking further confirmation. For example, Stebbing's (1914) report of Podontia quatuordecimpunctata on Ficus elastica Roxb. ex Hornem is that of adult feeding; this may be accidental, as is common in flea beetles, and does not necessarily indicate true trophic relationships. Anacardiaceae and Burseraceae are the unequivocally proven host plant families of Blepharida-group species. This has been confirmed by multiple observations and reports of natural history. These two plant families are closely related; Anacardiaceae, Burseraceae, and Sapindaceae belong to the Order Sapindales of Malvids, but Clusiaceae is phylogenetically distant from Malvids, being situated within the Order Malpighiales of Fabids (Judd et al. 2008). Our novel discovery of a Clusiaceae as host for a Blepharida-group taxon is intriguing. Other chrysomelid genera on Clusiaceae include Nodina Motschulsky, Homoschema Blake, and Megistops Boheman (Jolivet and Hawkeswood 1995). There is also a report of larvae of an unnamed beetle defoliating Garcinia gummi-gutta from India (Anonymous 2003), which is probably Podontia congregata. Despite being phylogenetically distant, it is possible that Garcinia gummi-gutta is chemically similar to Anacardiaceae and Burseraceae and it produces resinous gum like most Anacardiaceae. Interestingly, a similar pattern of host selection exists with leafhoppers (Hemiptera: Cicadellidae); Anacardiaceae are common host plants of Oriental Idiocerinae leafhoppers with ten species documented on mango, Mangifera indica L., alone (Viraktamath and Viraktamath 1985). Two species of the idiocerine genus Busoniomimus Maldonado Capriles occur in India (Viraktamath and Murphy 1980; Viraktamath and Viraktamath 1985); Busoniomimus mudigarensis (Viraktamath) feeds on Buchanania angustifolia Roxb. (Anacardiaceae) in south India (Viraktamath and Murphy 1980). The second species, Busoniomimus manjunathi Viraktamath and Viraktamath, feeds on mango (Viraktamath and Viraktamath 1985) and Garcinia gummi-gutta in Kerala (Mathew et al. 2002; KDP personal observations), showing a similar host plant selection to Podontia congregata.

At least three Podontia species are regarded as serious pests— Podontia affinis on Spondias dulcis in Indonesia, Podontia lutea on Toxicodendron vernicifluum in China, and Podontia quatuordecimpunctata on Spondias spp. At this time, Podontia congregata is a minor pest of Garcinia gummi-gutta, causing damage of little economic significance. The large size and fecundity of these species may contribute to their defoliating impacts. Documenting natural enemies as in Table 2 may be useful in finding biocontrol agents.

Species in six Blepharida-group genera are now documented with fecal retention—Blepharida (Becerra et al. 2001), Diamphidia and Polyclada (Chaboo et al. 2007), Ophrida (Lee and Cheng 2007), and Podontia (Barlow 1900; Corbett and Yusope 1921; Pramanik and Basu 1973; Takizawa 1978; Singh and Misra 1989). Both Pramanik and Basu (1973) and Singh and Misra (1989) mention an exudate covering the feces of Podontia quatuordecimpunctata. No such exudate was observed in Podontia congregata. Cast exuvial skins are retained in the larval fecal covering of Podontia lutea and Blepharida nigrotesselata Baly, but such inclusions have not been reported in other Blepharida-group species (Paterson 1943; Takizawa 1978). Among chrysomelids that retain a fecal covering, exuvial skin inclusions in larval and pupal fecal shields is a widespread and significant structural feature only in Cassidinae (Chaboo 2007 and citations therein). The gum-like substance covering the fecal thread, revealed through microscopic examination, probably acts as a binding material to create a single, unbroken thread that forms the fecal shield (Fig. 25).

Larvae may reduce enemy attack in several ways. Larvae which are large enough to feed by cutting the lamina position themselves on the abaxial side of the leaf and thus probably evade pouring rains as well as secure some cover from natural enemies. Young larvae prefer to feed on young, tender leaves. Older larvae feed on both light green tender leaves as well as tougher, darker green mature leaves. Fecal cover of larvae feeding on tender leaves is light green while that of those feeding on tougher mature leaves is dark green-grey, which may enhance any background camouflage effect. The fecal coats may further act as physical barriers against some predators and parasitoids. However, bugs may be specialist predators by virtue of their propensity to insert their beaks into the vulnerable ventro-lateral area of the body not covered by the fecal coat (Figs 15, 23). Host specific parasitoids, like Ooencyrtus podontiae, are also known to attack Podontia affinis (Gahan 1922).

Pupation within hard earthen cocoons is widespread among flea beetles and may reduce vulnerability to predators and parasites. Bose (1953) reported leaf inclusions in these cocoons. Such constructions may minimize desiccation, particularly in the drier habitats where many Blepharida-group species occur. Most pupation is underground which further enhances protection, but surface pupation occurs in Podontia congregata. Reports for Podontia quatuordecimpunctata are contradictory, indicating underground pupation (Corbett and Yusope 1921; Pramanik and Basu 1973; Sardar and Mondal 1983; Singh and Misra 1989; Baksha 1997; Deka and Kalita 1999) and surface pupation (Bose 1953; Singh and Misra 1989; Baksha 1997).

Podontia adults escape by thanatosis, whereby they fall from the foliage, remain motionless and thus disappear into the undergrowth. This defensive tactic is a widespread escape response among Chrysomelidae. Larvae appear to use an “anal extremity"to adhere to leaves (Pramanik and Basu 1973); this may be referring to the adhesive anal disc of the pygopods in some chrysomelids which acts as a holdfast organ, minimizing the risk of falling off hosts (Gustafson and Chaboo 2009).

Chrysomelids are well known for their chemical defenses (e.g., Pasteels et al. 1989, 1994) and Blepharida-group species have intimate ecological and evolutionary relationships with their host plants, and which appear to be chiefly driven by a chemical arms race based on host secondary metabolites (e.g., Becerra 2003). Blepharida-group species present two different strategies of chemical defense: (1) the sequestration of host plant chemicals for incorporation into their fecal defenses, and (2) an apparent synthesis of toxins by the beetle itself like in southern African taxa. As an example of the first strategy, chemical analyses of the feces of Blepharida rhois larvae (Morton 1997; Vencl and Morton 1998, 1999) revealed a mix of fatty acids, tannins, and phytol derived from its host plant, Rhus glabra Linnaeus, which function as deterrents to ant attack. As an example of the second strategy, diamphotoxin, a relatively small hemolytic and neurotoxic protein, has been isolated from larvae of Diamphidia nigroornata, one of the beetles used by southern African Kalahari San as a source of their arrow poisons (Koch 1958; Mebs et al. 1982; Woollard et al. 1984). It is unclear if this protein occurs in other species of Diamphidia, Polyclada, and Blepharida which are also suspected sources of arrow poison.

The monophyly of the Blepharida-group is supported by characters from host plants, beetle morphology, and behavior of all life stages (Takizawa 1978; Furth and Lee 2000; Chaboo et al. 2007). Takizawa's (2005) Podontia-group was based on eggs being deposited in rows; however Hsu (1934b) illustrates eggs of Podontia lutea clustered at the apex of a leaf. Farrell (1998) identified the relationship Podontia + (Orthocrepsis + Nisotra) based on = 18S ribosomal sequence (entire). Becerra (2004a, and subsequent studies) has focused on Blepharida and its co-evolutionary association with Bursera, but the similar host plant choices of Blepharida-group species suggest that Becerrra's coevolutionary model may be extrapolated to the entire Blepharida-group.

The host plant choices of Blepharida-group species are interesting to agriculturists, foresters, anthropologists, and chemists. In Brazil, India and Thailand, the pest species on economically important plants attract agricultural interests. In China, forestry officials are concerned about damage to forests and trees used in traditional medicine. Southern African species are the source of the San's indigenous arrow poisons. The Blepharida-group is a model for research on diverse questions.