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HEMIPTERA, Gelastocoridae -- <Images>
& <Juveniles> Please refer also to the following link for
details on this group: Gelastocoridae = Link 1 The Gelastocoridae or
toad bugs contain about 105 species. They resemble toads by their warty
appearance and movements. These riparian insects occur at the margins of
streams and ponds, where they are predators of other insects. The family has
a worldwide distribution, with most species occurring in the tropics. The following discussion
is derived primarily from Cassis et
al. (2002): Toad bugs average 6.1–11 mm long and have an ovoid body
with roughened surface, frequently with a warty appearance. The eyes are
large, and protruding with ocelli usually being present. The short antennae
have four segments. The labium is 4-segmented and does not extend beyond the
forecoxae. The pronotum is large, transverse and wider than the head. The
scutellum is triangular and large. The metathoracic scent glands are well
developed in the Gelastocorinae, and absent in the Nerthrinae. The larvae lack
dorsal abdominal gland openings. The forewings are mostly divided into
clavus, corium and membrane. Menke (1979) reported wing polymorphism as
common, with flight rare, particularly in Nerthra Say species. In some
species the hemelytra are fused along the midline (Todd 1960). Parsons (1960)
records a reduction in hind wings and wing musculature in Gelastocoris Kirkaldy.
The mid and hind legs are slenderand the forefemora are incrassate. The
foretarsi are diagnostic at the subfamily level, the Gelastocorinae having a
fully articulated, 1-segmented tarsus, with the foretarsus and tibiae fused
and a single claw on the pretarsus. The pretarsi of the forelegs are
asymmetrical, with the inner claw reduced. The hind tarsus is 3-segmented.
The abdominal sternites are asymmetrical, particularly in the males. The male
genitalia are asymmetrical with the left paramere reduced or absent. The
females lack a laciniated ovipositor (Parsons 1959, 1960; Slater 1982). Gelastocoris species
are found on the muddy banks of streams, ponds, lakes, swamps and roadside
ditches. Hungerford (1922) gave an account of the biology of the North
American species, Gelastocoris oculatus (Fabricius). Nerthra species
are found in a wide variety of habitats, including semiaquatic habitats, but
are sometimes found far from water. Todd (1955) reported Nerthra species
from leaf litter, under debris, in soil, and sometimes in decomposing plant
material, or cow dung. He reported the Neotropical species, Nerthra
nepaeformis (Fabricius), from banana plantations. Burrowing has been
given as a common behaviour of toad bugs, in both wet and dry conditions
(Bennett & Cook 1981). Both larvae and adults of the widespread species Nerthra
macrothorax (Montrouzier) are found in and under decaying vegetation of Pandanus
Parkinson and Erythrina indica Lam. (Todd 1960). The habitats of
other Australian species are poorly known. Carver et al. (1991) report
that most Australian species are found near water; a few species are
collected away from water, particularly in rainforest habitats, and N.
plauta Todd is found in association with spinifex. Toad bugs are
considered to be opportunistic predators and scavengers (Bennett & Cook
1981). Hungerford (1922) recorded them feeding on a variety of arthropods including
leafhoppers, various flies and a locust species. Checklist of the Gelastocoridae.
= = = = = = = = = = = References: Please refer to <biology.ref.htm>, [Additional references
may be found at: MELVYL
Library] Bennett, D.V.
& Cook, E.F. 1981. The semiaquatic Hemiptera of Minnesota
(Hemiptera: Heteroptera). Technical Bulletin. Agricultural Experiment
Station, University of Minnesota 332: 1-59 Carver, M.,
Gross, G.F. & Woodward, T.E. 1991. Hemiptera (bugs, leafhoppers, cicadas,
aphids, scale insects, etc.) [with contributions by Cassis, G.,
Evans, J.W., Fletcher, M.J., Hill, L., Lansbury, I., Malipatil, M.B., Monteith,
G.B., Moulds, M.S., Polhemus, J.T., Slater, J.A., Štys, P., Taylor, K.L.,
Weir, T.A. & Williams, D.J.].
2002. pp. 429-509 in
CSIRO (ed.). The Insects of Australia. A textbook for students and
research workers. Melbourne : Melbourne University Press
Vol. 1 xiii 542 pp. Family Gelastocoridae in Australian Faunal
Directory. Australian Government, Department of the Environment, Water,
Heritage and the Arts. URL consultato il 04-03-2009. Hungerford,
H.B. 1922. The life history of the toad bug. University of Kansas Science
Bulletin 24: 145-171 Menke, A.S.
1979. Family Gelastocoridae. pp. 126-130 in
Menke, A.S. (ed.). The Semiaquatic and Aquatic Hemiptera of California
(Heteroptera: Hemiptera). Berkeley : University of California Press Moreira da Costa
Lima, A. 1938. XXII. Ordem Hemiptera
in Insetos do Brasil. Tomo 2°, (in (PT)) Escola Nacional de Agronomia, pp.
312-314 Parsons, M.C.
1959. Skeleton and musculature of the head of Gelastocoris oculatus (Fabricius).
Bulletin of the Museum of Comparative Zoology, Harvard 122:
1-53 Parsons, M.C.
1960. Skeleton and musculature of the thorax of Gelastocoris oculatus (Fabricius).
Bulletin of the Museum of Comparative Zoology, Harvard 122:
299-357 Popov, Y.A.
1971. [Historical development of the hemipterous infraorder Nepomorpha.]. Trudy Paleontologicheskogo Instituta. Akademiya Nauk SSSR 129:
1-228 [In Russian] Rieger, C.
1976. Skelett und Muskulatur des Kopfes und Prothorax von Ochterus
marginatus Latreille. Beitrag zur Klärung der phylogenetischen der
Ochteridae (Insecta, Heteroptera). Zoomorphology
(Berlin) 83: 109-191 Slater, J.A.
1982. Hemiptera. pp. 417-447 in Parker, S.P. (ed.). Synopsis and
Classification of Living Organisms. New York : McGraw Hill Book Co Štys, P. &
Jansson, A. 1988. Check-list of recent family-group and genus-group names of
Nepomorpha (Heteroptera) of the world. Acta
Entomologica Fennica 50: 1-44 Todd, E.L.
1955. A taxonomic revision of the family Gelastocoridae (Hemiptera). Kansas
University Science Bulletin 37: 277-475 Todd, E.L.
1959. The Gelastocoridae of Melanesia (Hemiptera). Results of the Archbold
Expeditions. Nova Guinea ns 10: 61-94 Todd, E.L.
1960. The Gelastocoridae of Australia (Hemiptera). Pacific Insects 2:
171-194 Todd, E.L. 1961.
A checklist of the Gelastocoridae (Hemiptera). Proceedings of the
Hawaiian Entomological Society 17: 461-476 |