Neuroptera (Alder Flies, Snake Flies, Lacewings, Ant Lions, Etc.)
Small to rather large soft-bodied insects with usually elongate antennae. Mouthparts adapted for biting: ligula undivided or bilobed or often atrophied. Two pairs of very similar membranous wings, generally disposed in a roof-like manner over the abdomen
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NEUROPTERA (ALDER FLIES, SNAKE FLIES, LACEWINGS, ANT LIONS, ETC.) Small to rather large soft-bodied insects with usually elongate antennae. Mouthparts adaptedfor biting: ligula undivided or bilobed or often atrophied. Two pairs of very similar membranous wings, generally disposed in a roof-like manner over the abdomen when at rest. Venation primitive but with many accessory veins: costal veinlets numerous: Rs often pectinately branched. Abdomen without cerci. Larvae carnivorous, ofa modified campodeiform type with biting or suctorial mouthparts: the aquatic forms usually with abdominalgills. Pupae exarate, decticous: wings with complete tracheation. The heterogeneous group which formed the Neuroptera of Linnaeus is now divided into at least eight or nine well-defined orders, the original name being confined to the Megaloptera and Planipennia as enumerated below. The group thus restricted is still further dismembered by some authorities into two or three separate orders. Although it is evident that the Neuroptera exhibit at least three lines of evolution including marked divergence in their metamorphoses these several lines appear to be derivable from a common ancestral type. The species are rarely abundant in individuals, and most have weak powers of flight. They feed upon soft-bodied insects and liquid matter, such as honey-dew. With the exception of the Coniopterygidae, the Neuroptera are separable from the Mecoptera by the venational features enumerated above. The mouthparts are well developed with biting mandibles, the maxillary palps are s-segmented, the labial palps 3-segmented, and the ligula is reduced to the condition of a median and sometimes slightly bilobed process, or is totally atrophied. The wing-coupling apparatus is of the jugo-frenate type, though small, usually reduced and with distinct bristles; a frenulum, however, is present in Hemerobiidae. The tarsi have five segments and the abdomen ten. The morphology of the male genitalia (Killington, 1936; Tjeder in Tuxen O. W. Richards et al., Imms’ General Textbook of Entomology © O. W. Richards and R. G. Davies 1977
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GENERAL TEXTBOOK OF ENTOMOLOGY
(1970); Acker, 1960; Adams, 1969). An aedeagus may be present (Hemerobiidae), absent (Osmylidae), or even present or absent within one family (Coniopterygidae). In the first-named family it is associated with sternite 10. Gonocoxites probably occur in most groups (though not in Sialis) and may be articulated to the 9th tergite or to a structure, the 'gonarcus', formed of the fused parameres. In both sexes, tergite 10 commonly bears a group of trichobothria on each side. In the female, the genital aperture is behind sternite 8 which is rather reduced and may bear a pair of gonapophyses. Sternite 9 is more or less divided and may function as an ovipositor and its lobes may, indeed, be the coxites of an appendage. This seems more probable in Dilar and Raphidia which have long ovipositors (Tjeder, 1937; but cf. Ferris and Pennebaker, 1939). The egg-pore and the copulatory pore are independent in the M
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