LIBRARY

560 COLLEGE ENTOMOLOGY
(Net-winged Beetles.) . LYCIDlE
Middle coxre in contact; epipleura distinct; elytra not reticulate 3
3. Episterna of metathorax sinuate on inner side; head nearly or quite
covered by thorax; epipleura usually wide at base of elytra: phosphorescent
organs usually present. (Fireflies.) . LAMPYRlDlE
Episterna of metathorax not sinuate on inner side; head fully exposed;
epipleura narrow at base; anterior coxre with distinct trochantins;
elytra soft; no phosphorescent organs. Medium-sized predacious
beetles. (Leather-winged Beetles.) . CANTHARIDlE
4. Hind coxre prominent, at least internally 5
Hind coxre fiat, not prominent . 6
5. Body with extensible vesicles . MALACHIIDlE
Body without extensible vesicles MELYRIDlE
6. Fourth segment of tarsus small; pronotum separated from propleura
CORYNETIDlE
Fourth segment of tarsus normal; pronotum not separated from propleura
. . CLERIDlE
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Family LAMPYRIDJE Leach 1817 (Lam-pyr'i-dre, from the Greek XafJ,7rvpts,
a glowworm; referring to the luminous larviform females). German,
Leuchtkiifer. Fireflies, Glowworms.
Small to medium-sized, flat soft-bodied elongated nocturnal beetles, which
are usually smooth or slightly pubescent; black, brown, yellow, or red in color
and luminous 1 in many species. The adults are either beetle-like in form or the
females of a number of genera are larviform and totally different from the
males. Head small, free or wholly or partly covered beneath the pronotum;
rarely somewhat prolonged into a snout. Antennre inserted on the frons. 11segmented,
pectinate or flabellate in the males. Eyes may be very large in the
males. Thorax large. pronotum covering head in some forms. Legs normal.
Fore coxre subconical, middle contiguous, hind transverse. Tarsal formula
5-5-5 or rarely 4-5-5 in males. Elytra leathery. long or reduced, and not always
meeting in a straight line at the apices. Wings well developed except in the
larviform females. Abdomen with six to seven visible sternites, the first immovable.
Luminous organs on segments VI and VII and also on others. The
light is variable and may be present only in the female glowworms; in other
species it may be stronger in either sex; in color the light varies from yellowishgreen
to green, orange, or red. The eggs,2 larvre, and pupre of certain forms
may also be luminous. The larvre are flat, elongated, distinctly segmented;
head small with sickle-shaped mandibles; legs well developed; thoracic and abdominal
tergites sclerotized; photogenic organs may be present on a pair of
round patches on abdominal segment VIII.
1 Luminosity occurs in a number of widely separated groups of insects in the families
ELATERIDJE. LAMPYRIDJE. and PHENGODIDJE in the order COLEOPTERA and in
the family.MYCETOPHILIDlE of the order DIPTERA. The luminous organs are composed
of cells whIch are developed from the fat body but have many more nerves and tracheal capillariell
which are thought to aid in oxidation and combustion which produce the light. (See
Baldur, Bionomics oj Enlomophagus Coleoptera. pp. 87-94, 1935.)
2 In realit.y the embryonic larv.e become luminous before hatching from the eggs.