FNZ 19 - Mantodea (Insecta) - Suborder Mantodea
Ramsay, GW 1990. Mantodea (Insecta), with a review of aspects of functional morphology and biology. Fauna of New Zealand 19, 96 pages.
(
ISSN 0111-5383 (print),
;
no.
19.
ISBN 0-477-02581-1 (print),
).
Published 13 Jun 1990
ZooBank: http://zoobank.org/References/9BB875C2-A2DF-4BCE-9CAF-985FFC0FCAB2
Suborder Mantodea
Praying mantids are exopterygote insects, that is, their wings develop as external buds on the thorax of the nymph and increase in size at each moult. The wings are hinged through a series of sclerites and so can be folded along the body - a characteristic of the insect infraclass Neoptera. Mantids are moderate-sized to large insects with typical orthopteroid mouthparts (i.e., mandibles, maxillae, etc., developed for biting and chewing) and with large raptorial forelegs which have elongate, mobile coxae. All species are predaceous, capturing insects or spiders.
The head, which is not covered by the pronotum as it is in the Blattodea, is freely movable with large, globose or conical compound eyes and three ocelli; the ocelli are sometimes larger in males, and occasionally are lost in females. The antennae are slender and filiform, with numerous segments. The maxilla has five-segmented palps and the labium three-segmented palps.
The pronotum is usually elongate, narrow, and movably attached to the mesothorax. The femora and tibiae of the raptorial forelegs have rows of spines on their opposing surfaces, and the tibia terminates in a sharp, curved spur. The middle and hind legs are normal walking legs with no special modifications. All tarsi are five-segmented. There are two pairs of wings, which may be reduced or absent in females. At rest the wings are folded along the abdomen. The forewing is narrow and leathery, with a small anal lobe, and the hind wing is membranous with a narrow anterior blade and broad, fan-like anal lobe. The venation of both wings is characteristic in mantids, and is discussed in detail on pp. 36-41.
The dorsoventrally flattened abdomen comprises eleven segments including one or more reduced terminal segments. There is a pair of segmented cerci in both sexes. The male genitalia are asymmetrical, the ninth stemum (subgenital plate) usually bearing a pair of styli. In the female the seventh stemum forms a cleft subgenital plate which surrounds the three pairs of small valves of the ovipositor.
The alimentary canal is relatively short and straight, with a large crop, a six-toothed or six-ribbed proventriculus, and eight mid-gut caeca. There are more than a hundred fine Malpighian tubules.
The diploid chromosome number ranges from 15 to 39, and the males are mostly XO, although in some genera the sex determination system is X, X2 Y.
The egg -case (ootheca) of mantids is unique. From 10 to 400 or more eggs are laid in a homy ootheca which may be enveloped in a lighter, spongy envelope also produced by the female's accessory glands. The ootheca, which has a characteristic form in each genus or species, is usually attached to surfaces such as stems, bark, or rocks, but is placed in the soil by members of some genera. The embryos form a pair of chitinous hatching threads (unique amongst arthropods) from which the newly emerged nymph is suspended during its first moult. The nymphs (miniature adults) increase in size at each moult, of which there are from five to nine, and the wing-pads, genitalia, and antennal segments increase proportionately at each stage. The wing pads do not reverse their orientation in the later nymphal stages, as they do in other orthopteroid insects such as the Gryllacridoidea, Tettigonioidea, Grylloidea, and Acridoidea.
The coloration of mantids tends to be cryptic, matching that of their preferred habitat - foliage, or bark, or the soil surface, and so on. Sometimes leaf-like expansions of the body and limbs are developed. Many species have bold, striking markings on the wings and forelegs which may serve to visually startle or warn would-be predators, but which may also attract prey in some instances.
The specialised raptorial forelegs of the Mantodea are not unique amongst insects. They occur in similar form amongst such diverse groups as the Mantispidae (Neuroptera), Emesinae (Reduviidae, Hemiptera), and Hemerodromiinae (Empididae, Diptera). Some of these are confused with mantids by the uninformed.
Other characters also distinguish the Mantodea: the possession by many species, if not all, of a forewing pterostigma or incipient pterostigma; the presence of a tympanate auditory organ in the mid-ventral longitudinal rnetathoracic groove of many species (Yager 1989); the presence of a femoral brush on the inner distal aspect of the fore femur; the articulation of the antenna with the head capsule comprising a long, rod-like mid-ventral projection of the antennal selerite; the presence of anastomosing ridges alternating with teeth in the proventriculus; in the forewing, the presence of a proximal lobe bounded by the peripheral vein leading to a weak cubital furrow; and in the hind wing the absence of the first vannal vein, except in primitive species, and the presence of an r-cu1 cross-vein.
The distribution of Mantodea is essentially tropical to subtropical, with a few species in temperate regions (Beier 1939). The order comprises approximately 1800 species, organised into more than 320 genera and eight families.
General accounts of the Mantodea have been given by Sharp (1895), Chopard (1949), Beier (1964, 1968), Key (1970), Kaltenbach (1976), Richards & Davies (1977), and Brown (1982).
The close relationship and common origin of the Mantodea and Blattodea has long been acknowledged, and has been briefly summarised by Judd (1948). Characters in common are: presence of unpaired abdominal ganglia in the nervous system; similar external morphology, abdominal musculature, and abdominal appendages; scape articulation with the head capsule comprising a mid-ventral extension of the antennal sclerite; proventriculus conical, with eight tubular gastric caeca at its junction with the midgut; internal structure of the proventriculus almost identical; forewing Cu2 characteristically curved, and branching of Cu1 similar (Ragge 1955); arrangement of vannal veins of hind wing identical, except that IV is lost in mantids (Ragge 1955).