Ascalaphidae is a family of in the order Neuroptera, commonly called owlflies; there are some 450 extant species. They are fast-flying crepuscular or Diurnality predators of other flying insects, and have large bulging eyes and strongly knobbed antennae. The larvae are ; some of them make use of self-decoration camouflage.
Description
Owlflies are readily distinguished from the superficially similar
dragonflies by their long, clubbed antennae; dragonflies have short, bristle-like antennae. The closely related antlions (family
Myrmeleontidae) have short, weakly clubbed antennae, smaller eyes, and reticulate
wing venation.
All but one species of Ascalaphidae have long antennae, easily distinguishing them. The sole exception is the Brazilian
Albardia, the only living member of the subfamily
Albardiinae, which has short antennae, but these are strongly clubbed (compared to myrmeleontids), and its wing venation is reticulate, typical of ascalaphids. Most owlflies are about in length, not including antennae.
Adult owlflies of the family
Ululodinae such as
Ululodes have large divided eyes and
crepuscular habits, which is where the common name "owlfly" came from.
Owlflies are worldwide in distribution, occurring in warm temperate and tropical habitats; there are some 450 extant species.
Ecology
Adult owlflies are fast-flying, aerial
, capturing and feeding on other insects in flight.
The larvae too are predatory, making owlflies important in maintaining a natural ecological balance and helping to control pest insects.
Adults of many New World species are most active at sunset, and can often be collected near lights. During the day, adults rest on stems and twigs with the body, legs, and antennae typically pressed to the stem.
Anti-predator defences
When disturbed, some owlflies release a strong,
musk-like chemical to deter enemies.
The abdomen in
Ululodes quadrimaculatus is raised at rest,
mimicry a broken twig.
Some New World species such as Haploglenius luteus are able to suddenly reflex a flap on the pronotum, exposing a strongly-contrasting patch of pale colour (white or cream), either as a deimatic display to startle predators,
Life cycle
Eggs are laid on twigs or plant stems. Owlfly
are
, and sequester themselves at the soil surface, in ground litter, or on vegetation, sometimes covered with debris, and wait for prey, which they seize with their large, toothed mandibles. They resemble
antlion larvae, but have an elongate, sometimes finger-like appendage on the side of each segment called a scolus-like process.
In some genera, larvae actively place sand and debris onto their dorsum as self-decoration camouflage.
occurs in a spheroidal silk cocoon in
leaf litter or soil.
Evolution
Owlflies appear to have evolved from a common ancestor with
Stilbopteryginae.
These, in turn, evolved from a common ancestor with
Palparinae, which evolved from a common ancestor with the true antlions, or
Myrmeleontidae.
Taxonomy and etymology
The family Ascalaphidae was first described by the French entomologist Jules Pierre Rambur in 1842.
The name is from Greek
askalaphos, a kind of owl.
In
Greek mythology, Ascalaphos was the custodian of the orchard of
Hades, god of the underworld; the goddess
Demeter transformed him into an owl.
Fossil history
The owlflies are known from
of adults and larvae, often encased in
Baltic amber. Most of these cannot be placed in a particular subfamily. Most are known from the
Oligocene.
The
Late Jurassic Mesascalaphus was thought to be a more basal member of the family, but it is now believed to be a member of
Mesochrysopidae.
Phylogeny
Total evidence analysis (several genes + morphology) in 2019 recovered Ascalaphidae as
monophyletic and found evidence for five subfamilies: Albardiinae van der Weele, 1909; Ululodinae van der Weele, 1909; Haplogleniinae Newman, 1853; Melambrotinae Tjeder, 1992; and Ascalaphinae Lefèbvre, 1842.
This refuted nuclear
Phylogenetics in 2018, which recovered Ascalaphidae as a
paraphyletic lineage within Myrmeleontidae.
Molecular analysis in 2018 using
Mitochondrion Ribosomal RNA and mitogenomic data also placed the Ascalaphidae as sister to the
Myrmeleontidae as the most advanced groups within the
Neuroptera.
The
fossil record has contributed to an understanding of the group's phylogeny.
[Parker, S. P. (ed.), 1982: Synopsis and classification of living organisms. Vols. 1 & 2. McGrew-Hill Book Company] The phylogeny of the owlflies has remained uncertain, with many of the higher taxa apparently not natural groups (
).
External
Neuropteran subfamilies are described in Winterton and colleagues 2017 and Jones 2019.
Internal
Machado et al 2018 proposes a classification below family level, into tribes (names ending with –ini):
Groups formerly considered part of "Myrmeleontidae" are underscored and marked "Myrm."
Jones 2019 presents a total-evidence phylogeny, preferring to classify only to family level:
External links
