The Lasiocampidae, together with a few small families, differ from the majority of this group in wanting a frenulum.
Several of the families in this group have lost the frenulum.
Jugatae: that series of Lepidoptera in which there is a jugum instead of a frenulum to unite the wings in flight.
Connected with this organ is a small tough membrane or ligament called the frenum which corresponds to the frenulum of the male.
This process is termed the retinaculum, and serves, in conjunction with the frenulum, to lock the wings together during flight.
In butterflies there is no frenulum, but a costal outgrowth of the 466 hindwing subserves the same function.
The hindwing carries a frenulum and has its sub-costal nervure connected with the radial by a short bar.
The maxillary palps are absent or vestigial, and a frenulum is usually present on the hindwing.
The maxillae are well developed, the hindwing has a frenulum, and its sub-costal nervure touches the radial near the base.
The Notodontidae are stout, hairy moths (figs. 5, 41, 42 a) with maxillae and frenulum developed.
frenulum fren·u·lum (frěn'yə-ləm)
n. pl. fren·u·la (-lə)
A small frenum or band of fibrous material.