Leptoglossus gonagra (Fabricius)

Synonyms. Leptoglossus australis (Fabricius), Leptoglossus membranaceus (Fabricius)

Family. Coreidae

Order. Hemiptera

Common name. Squash bug, kepik labu (Indonesia)

Distribution. Leptoglossus gonagra is found in Africa, the Caribbean, Central America, North America, Southern Asia, Micronesia, and the tropical and subtropical regions of Australia.

Host plants. Leptoglossus gonagra is a polyphagous insect known to feed on various plants, including snake gourd, melon, cucumber, pumpkin, and other cucurbits. Additionally, it has been reported to feed on citrus, eggplant, guava, legumes, passionfruit, and tomato. 

Description and biology. Adults of this species are typically 18-24 mm long and have a black or dark brown coloration. They can be recognized by a curved orange line behind their head, as well as their long, banded antennae that feature black and orange stripes (Figure 1). 

Figure 1. Leaf-footed bug Leptoglossus gonagra (Photo: © Aunu Rauf)

Additionally, the underside of their thorax and abdomen have small orange spots, while their rear legs are enlarged and flattened, and each of the two tibiae has a pair of orange spots (Figure 2).

Figure 2. Leptoglossus gonagra (Photo: © Aunu Rauf)

The female insects lay their eggs in batches of approximately 30 on the leaves, stems, and even the tendrils of the plant. After 6-7 days, the eggs hatch into nymphs. The nymphs go through five stages over 40-50 days. Initially, the young nymphs are reddish in color, but as they progress from one molt to the next, they become darker. They tend to cluster together in the beginning but gradually disperse more widely around the plant.

Nature of damage. Damage is caused by both nymphs and adult sucking sap from stems and tender fruits. Stems turn yellow-brown and they may die if infestations are high. Feeding on fruits causes them to shrivel, rot and drop. Secondary fungal infection by Nematospora may occur on citrus fruits. The bugs are not considered major pests, and only occasionally reach numbers that cause economic damage. 

Natural enemies. Little is known about its natural enemies.

References

Butani DK. 1979. Insects and Fruits. Delhi: Periodical Expert Book Agency.

Fondio D, Yeboue NL, Soro S, Tano DKC. 2020. Biological parameters of Leptoglossus membranaceus Fabricius. 1781 (Heteroptera: Coreidae) cucumber pest (Tokyo F1 and poinsett varieties) in the rainy season in Daloa (Cote d'Ivoire). J Entomol Zool Studies 8(2): 1618-1624.

Kalshoven LGE. 1981. Pests of crops in Indonesia, (Revised and translated by PA van der Laan). Jakarta: PT Ichtiar Baru.

Shepard BM, Carner GR, Barrion AT, Ooi PAC, van den Berg H. 1999. Insects and their natural enemies associated with vegetables and soybean in Southeast Asia. Orangeburg (SC), USA: Quality Printing Company.

van Reenen JA. 1973. Behaviour and biology of Leptoglossus membranaceus (Fabricius) in the Transvaal, with description of the genitalia (Heteroptera: Coreidae). Annals of The Transvaal Museum 28(14): 257-286.

Author: Aunu Rauf.

Citation: https://indoagriinsecta.blogspot.com/2024/02/leptoglossus-gonagra.html

Vatiga illudens (Drake)

Family. Tingidae.

Order. Hemiptera.

Common name. Cassava lace bug, kepik renda singkong (Indonesia).

Distribution. The native ranges of V. illudens include the Carribean, Guyana, Brazil, Colombia, Ecuador, Cuba, Peru, Paraguay, Argentina, and Venezuela. Recently, well-established populations of V. illudens have been reported from Florida (USA) and Reunion Island (Africa). The presence of the insect in Indonesia was first reported from East Java by Puspitarini et al. (2021). It has now spread widely throughout Java and Sumatera.

Host plants. Cassava (Manihot esculenta Crantz).

Description and biology. Adults of V. illudens are ash gray and measure about 3 mm long by 1 mm wide (Figure 1). The average life cycle of V. illudens lasts 22.0 days. Adult females live about 64.5 days with a preoviposition period of 7.0 days; while males live 17.7 days. The adults do not normally fly when on the plant, but do so over several meters when provoked.

Figure 1. Adult of Vatiga illudens (Photo: © Aunu Rauf)

The female can lay, on average, 145.3 eggs, which she inserts into leaf tissue, preferably next to central nerves where they converge near the petiole. They thus become unnoticeable. The egg stage lasts approximately 10.1 days. Nymphs are off-white in color, with numerous spinules over their body (Figure 2). These nymphs undergo five instars whose average duration is 11.9 days.

Figure 2. Nymph of Vatiga illudens (Photo: © Aunu Rauf)

Both adults and nymphs are found in large quantities on the undersides of leaves (Figure 3), and show preference for the basal and middle leaves of plants. Lace bug attacks occur mainly during the dry season.

Figure 3. The colony of Vatiga illudens on the underside of cassava leaf (Photo: © Wawan Yuandi)

Nature of damage. Adults and nymphs feed on the undersurface of the lower plant leaves. Damaged leaves have small yellow spots that later turn reddish brown, resembling mite damage. This damage can reduce plant photosynthesis. In severe cases, the affected leaves have an almost white appearance (Figure 4). Potential yield losses caused by this insect is not known. 

Figure 4. Cassava leaf damaged by Vatiga illudens (Photo: © Aunu Rauf)

Natural enemies. A hemipteran of the family Miridae (Stethoconus sp.) (Figure 5) was observed preying on the nymphs and adults of V. illudens in the field.

Figure 5. Predatory mirid Stethoconus sp. (Photo: © Aunu Rauf)

Additionally, several lace bugs were infected by an entomopathogenic fungus (Figure 6).

Figure 6. Adult of Vatiga illudens infected by entomopathogenic fungus (Photo: © Aunu Rauf)

References

Halbert S. 2010. The cassava lace bug, Vatiga illudens (Drake) (Hemiptera: Tingidae), a new wxotic lace bug in Florida. Pest Alert. FDACS-P-01727. Florida Department of Agriculture and Consumer Services.

Puspitarini RD, Fernando I, Setiawan Y, Anggraini D, Rizqi HA. 2021. First record of the cassava lace bug Vatiga illudens (Drake, 1922) (Hemiptera: Tingidae) from East Java, Indonesia. Biodiversitas 22(7): 2870-2876.

Streito J-C, Guilbert E, Merion S, Minatchy J, Pastou D. 2012. Premier signalement de Vatiga illudens (Drake, 1922), nouveau ravageur du Manioc dans les Mascareignes (Hemiptera: Tingidae). L'Entomologiste, tome 68 (6): 357-360.

Yasunaga T, Takai M, Nakatani Y. 1997. Species of the genus Stethoconus of Japan (Heteroptera, Miridae): Predaceous Deraecorine plant bugs associated with lace bugs (Tingidae). Appl Entomol Zool 32(1): 261-264.

Wengrat APGS, Rondon C, Barilli DR, Uemura-Lima DH, Fredrich JE, Pratis SBQ, Pietrowski V. 2015. Biologia de Vatiga illudens (Drake) (Hemiptera: Tingidae) em mandioca (Manihot esculenta Crantz). XVI Congresso Brasileiro de Mandioca.

Author: Aunu Rauf.
Citation: https://indoagriinsecta.blogspot.com/2024/01/vatiga-illudens.html