La Błeszyński, 1966

La Błeszyński, 1966

This is a small genus with four species described from the south-western United States of America, Colombia, Peru, and Bolivia. The moths of the additional five Galápagos species are often smaller than those from North and South America, the latter reaching between 20 and 29 mm in wingspan for La cerveza Landry, 1995 and La paloma Błeszyński, 1966, the two continental species for which this information is known to us. The general coloration is brown in the species already described whereas two of the Galápagos species are greyish brown. The male genitalia in all species have a pair of costal projections on each valva and the phallus is apically enlarged with pointed projections laterally, the latter having been identified as a synapomorphy for the genus ( Landry, 1995). The larval food and morphology are unknown thus far. A possible synapomorphy for the Galápagos species of La is in the male genitalia, which have the manica adorned dorsally with narrow, pointed scales of medium length (see Figs 45b View Figs 44-46 , 47b, 49b View Figs 47-49 ). This character is not observed in La paloma. The reduced tympanal organs of the Galápagos species may also represent a synapomorphy ( Fig. 44 View Figs 44-46 ). Following the terminology used in Landry (1995), these organs can be described as follows: tympanic ridge thin, straight or broadly v-shaped; tympanic pockets almost inexistant; venulae secundae well developed; tympanic bridge long, almost half as long as venulae primae; tympanic crest not observed, apparently absent; tympanic drums narrow, very short, extending posteriorly only to base of reduced praecinctorium. The forewing length over width ratio is sexually dimorphic, with the female forewing being slightly narrower in all species of the Galápagos.

The grey-brown cluster of species

This group of two species of grey-brown moths is present on the younger islands of the archipelago (less than 1.55 myo, i.e., Fernandina, Floreana, Genovesa, Isabela, Pinta , and Santiago), but missing from the older islands of Española , San Cristóbal, Santa Fé, and Santa Cruz (more than 2.1 myo) (see Schmitz et al., 2007). They clearly form a separate group of species based on the colour of the moths, but also based on male genitalia characters such as the lateral projection of the costal process shorter than the cucullus, apically rounded, and without setae on the median side, the lack of anterior lobe on the lateral extensions on each side of the phallus apical part, and with the phallus broadly rounded apically in contrast to a more narrowly-rounded apex in the brown cluster of species. In female genitalia, the apical margin of the papillae anales is straight while it is medially produced in the brown cluster of species. Two species are recognized: La florenciae sp. nov., a single island endemic on Floreana , and La grisea sp. nov., occurring on Fernandina, Genovesa, Isabela, Marchena, and Pinta.