455
Anthribidae (fungus weevils) consist of about 360 genera and 4000 species, a
few of which, particularly species of Araecerus and Anthribus, are cleptoparasitoids
of soft scales such as Lecanium (Ülgentürk 2001; Ülgentürk and Toros 1996;
Valentine 2002). The female weevil oviposits her eggs under a soft scale insect and
the weevil larvae develop at the expense of the host’s eggs (Valentine 2002;
Mermudes and Leschen 2014). The earliest fossil record of Anthribidae is mid Early
Cretaceous, about 132 million years ago (Gratshev and Zherikhin 2003), although it
remains unknown when the cleptoparasitoid habit commenced in this lineage.
Coleoptera parasitoids, compared to the two other major parasitoid offenders,
Diptera and Hymenoptera, have a relatively narrow range of hosts, attacking eight
orders within the single phylum Arthropoda (Eggleton and Belshaw 1992). Host
searching is overwhelmingly accomplished by the larva in Coleoptera, as in Diptera,
but unlike Hymenoptera in which the host-searching stage is an adult. Among the
ten families of Coleoptera, the parasitoid condition originated at least 14 times
(Eggleton and Belshaw 1992), and likely several more times once a reliable phylogeny of Scarabaeidae has been established. These originations have arisen from two
major ancestral strategies (Eggleton and Belshaw 1992; Morris 1998), although the
transitions to parasitoidism involve mycophagy, nest provisioning, saprophagy and
phytophagy (Fig. 11.4a). The first strategy is from mycophagy, often associated
with nest provisioning, typical of Bothrideridae, Meloidae, Rhipiceridae and
Ripiphoridae. In this pathway, the candidate parasitoid larva is transported via
phoresy. It then first feeds on fungi in bark-beetle wood borings, followed by parasitism, or parasitoidizing or killing the existing beetle occupant (Morris 1998).
Cleptoparasitoidism originated in blister beetles that feed on pollen in bee nests, and
among weevils that feed in the wood borings of bark and ambrosia beetles. A modification of this strategy is found in scarabaeid parasitoids that may have originated
ancestrally as saprophages or mycophages associated with nest provisioning
(Eggleton and Belshaw 1992). The second strategy is exemplified by aleocharine
parasitoids that originated from predaceous precursors. Both strategies have resulted
in a greater number of cleptoparasitoids than ectoparasitoids plus endoparasitoids,
amounting to a majority of all beetle parasitoids. This cleptoparasitoid to ectoparasitoid and endoparasitoid ratios are unlike analogous proportions in all other parasitoid containing insect orders. Shifts away from the parasitoid life habit have been
rare among Coleoptera, involving egg predation and cleptoparasitic provisioning.
11.5.2.3 Strepsiptera (Twisted-Wing Parasites)
Strepsiptera are (controversially) internal parasites or parasitoids; they consist of
two suborders, 17 extinct and extant families and about 610 species (Table 11.1).
Males resemble normal, adult, winged insects, but have vestigial mandibulate
mouthparts, distinctive compound eyes and halteres as forewings (Cook 2014).
Female strepsipterans are larviform, live in the host wedged within the intersegmental membrane between abdominal sclerites but have a projecting orifice, the brood
canal that is used for mating. Strepsipteran triungulin larvae are structurally
11 The History of Insect Parasitism and the Mid-Mesozoic Parasitoid Revolution
Anthribidae (fungus weevils) consist of about 360 genera and 4000 species, a
few of which, particularly species of Araecerus and Anthribus, are cleptoparasitoids
of soft scales such as Lecanium (Ülgentürk 2001; Ülgentürk and Toros 1996;
Valentine 2002). The female weevil oviposits her eggs under a soft scale insect and
the weevil larvae develop at the expense of the host’s eggs (Valentine 2002;
Mermudes and Leschen 2014). The earliest fossil record of Anthribidae is mid Early
Cretaceous, about 132 million years ago (Gratshev and Zherikhin 2003), although it
remains unknown when the cleptoparasitoid habit commenced in this lineage.
Coleoptera parasitoids, compared to the two other major parasitoid offenders,
Diptera and Hymenoptera, have a relatively narrow range of hosts, attacking eight
orders within the single phylum Arthropoda (Eggleton and Belshaw 1992). Host
searching is overwhelmingly accomplished by the larva in Coleoptera, as in Diptera,
but unlike Hymenoptera in which the host-searching stage is an adult. Among the
ten families of Coleoptera, the parasitoid condition originated at least 14 times
(Eggleton and Belshaw 1992), and likely several more times once a reliable phylogeny of Scarabaeidae has been established. These originations have arisen from two
major ancestral strategies (Eggleton and Belshaw 1992; Morris 1998), although the
transitions to parasitoidism involve mycophagy, nest provisioning, saprophagy and
phytophagy (Fig. 11.4a). The first strategy is from mycophagy, often associated
with nest provisioning, typical of Bothrideridae, Meloidae, Rhipiceridae and
Ripiphoridae. In this pathway, the candidate parasitoid larva is transported via
phoresy. It then first feeds on fungi in bark-beetle wood borings, followed by parasitism, or parasitoidizing or killing the existing beetle occupant (Morris 1998).
Cleptoparasitoidism originated in blister beetles that feed on pollen in bee nests, and
among weevils that feed in the wood borings of bark and ambrosia beetles. A modification of this strategy is found in scarabaeid parasitoids that may have originated
ancestrally as saprophages or mycophages associated with nest provisioning
(Eggleton and Belshaw 1992). The second strategy is exemplified by aleocharine
parasitoids that originated from predaceous precursors. Both strategies have resulted
in a greater number of cleptoparasitoids than ectoparasitoids plus endoparasitoids,
amounting to a majority of all beetle parasitoids. This cleptoparasitoid to ectoparasitoid and endoparasitoid ratios are unlike analogous proportions in all other parasitoid containing insect orders. Shifts away from the parasitoid life habit have been
rare among Coleoptera, involving egg predation and cleptoparasitic provisioning.
11.5.2.3 Strepsiptera (Twisted-Wing Parasites)
Strepsiptera are (controversially) internal parasites or parasitoids; they consist of
two suborders, 17 extinct and extant families and about 610 species (Table 11.1).
Males resemble normal, adult, winged insects, but have vestigial mandibulate
mouthparts, distinctive compound eyes and halteres as forewings (Cook 2014).
Female strepsipterans are larviform, live in the host wedged within the intersegmental membrane between abdominal sclerites but have a projecting orifice, the brood
canal that is used for mating. Strepsipteran triungulin larvae are structurally
11 The History of Insect Parasitism and the Mid-Mesozoic Parasitoid Revolution