Moths of the Amazon
Superfamily - NOCTUOIDEA
Family - NOTODONTIDAE
subfamily - DIOPTINAE
Tribe - DIOPTINI
Rio Madre de Dios, 400m, Peru ©
Dioptinae comprises of 456 known species arranged into 2 tribes and
43 genera. The moths are almost entirely neotropical in
distribution: only one species Phryganidia
californica being found north of Mexico. All are day-flying,
and most are brightly coloured, typically with aposematic patterns
in yellow, orange or white on a black ground colour. They are
involved in Batesian mimicry rings with various Ithomiine
butterflies, and with moths from the subfamilies Arctiinae (
Erebidae ) and Sterrhinae ( Geometridae ).
Dioptinae, like most other moths have tympanal organs 'ears' at the
base of the thorax. These are generally accepted as having evolved
to allow them to detect the echo-location calls of predatory bats.
These moths however are all day-flying species, and experiments have
shown that they are virtually deaf. This implies that their
ancestors were nocturnal, and that the ability to hear was lost when
they evolved to become day-flying and were no longer exposed to
Euchontha are similar in appearance to
certain species of Sterrhinae and Arctiinae but can easily be
distinguished from them by their distinctive venation and the
presence of prominent orange spots on the thorax. There are 12 known
species, all confined to the Amazonian region.
Euchontha frigida is distributed along
the eastern Andes from Colombia to Peru.
This species occurs in primary rainforest, typically in the vicinity
of small streams, at altitudes between about 200-1000 metres.
The larvae of Dioptinae are cylindrical, usually slightly
translucent greenish in colour and marked with dark bands along the
back and sides. They have a sparse covering of short setae. I have
no information regarding the larval foodplants of
Euchontha, but other species of
Dioptinae typically feed on Passiflora
( Passifloraceae ) or Tumera (
moth is commonly found in two's and three's imbibing mineralised
moisture on sandbanks, dry river beds and urine-soaked ground in
lowland rainforest. It usually feeds at wet ground where water from
streams laps against rocks or gravel.
adults always feed and rest with the wings folded back and held flat
against the substrate.