This family comprises 70 species in four genera, all
from the Americas (Mound & Marullo, 1996). They have 9-segmented
antennae, with distinctive sensoria that comprise a continuous porous
band around the apex of segments III and IV. Little is known of their
biology, but they are probably all flower-feeders, and some species
are host specific. Sometimes they are locally common, but none is
known to damage any crop.
Available names: Original name Heterothrips
arisaemae Hood, 1908.
Biology: So far as is known, this species breeds only in the
flowers of the pitcher plant, Arisaema triphyllum, commonly
known as Jack-in-the-Pulpit.
Distribution: Eastern North America.
Recognition: Body brown, tarsi and apices of tibiae yellow;
antennae brown, segment III yellow; forewing brown with sub-basal
white band. Antennal segment III elongate conical, basal stem divided
into 3 sections, apical sensorium continuous around segment with irregular
double row of pores. head with setae small, one pair arising within
ocellar triangle. Pronotal setae all short, surface with little sculpture.
Metanotum with transverse lines of sculpture on anterior half but
concentric lines on posterior half, all bearing microtrichia. Tergites
II to VIII with median pair of setae long and close together medially;
lateral thirds of tergites with many discal microtrichia and posterior
margins with long microtrichia arising from small plates; tergites
VI, VII and VIII with posteromarginal comb complete medially. Sternites
with numerous discal microtrichia and 4 pairs of marginal setae.
Male micropterous with very small wing lobe; sternites III to VIII
with broadly oval glandular area medially.
Related species: More than 60 species are known in this genus.
Mound & Marullo (1996) provided a key to these, but identification
of many is difficult because of the lack of studies on intraspecific
Generic relationships: Four genera are currently recognised
in the Heterothripidae, all from the
New World, but most of the species are placed in the genus Heterothrips.
Species in these genera have 9-segmented antennae that, unlike the
species of Melanthripidae, have the sensoria
on segments III and IV continuous around the apex of these segments.
The wings are slender as in species of Thripidae.