MICROLEPIDOPTERA OF JUAN FERNANDEZ ISLANDS — CLARKE 33 



very strongly marked white areas between the dark basal area and 

 fii-st transverse Ime. Actually, the white scaling is so dense that the 

 light areas appear as oblique white bands. In one specimen, also, 

 the white scales are mixed with ocherous but only one shows this 

 feature. In other paratypes the white scaling is almost nonexistent 

 and even the dark markings are obscured. On the underside several 

 variations of the dark markings, usually preceded and followed by 

 light scaling, are found. These consist of breaks in the transverse 

 bands, complete replacement of the light terminal areas, with fuscous 

 shading into the lines with the consequent reduction of the transverse 

 line of forewing to an obscured costal spot. Despite all these varia- 

 tions, a series of 10 male and female slides leaves only one conclusion 

 to be drawn — that these represent one species only. 



In genitalia, grisea is nearest abbreviata from which it differs as 

 described under the latter species. 



Juania nitidissima, new species 



Figure 27 



Alar expanse 13 mm. 



Labial palpus creamy white; second segment dark gray on outer 

 side except ventrally; third segment whoUy overlaid with dark gray. 

 Antenna grayish fuscous. Head, thorax, and ground color of fore- 

 wing grayish fuscous with brassy hue; tegula somewhat lighter than 

 center of thorax; in cell and along termen fuscous shading but no 

 distinct, well-defined dark markings; cilia gray with a narrow, dark, 

 basal line. Hindwing grayish fuscous, slightly lighter basally; cilia 

 grayish fuscous with darker basal line. Legs gray, hindtibia and 

 tarsi paler. Abdomen gray, paler beneath. 



Female genitalia (slide 10703) : Ventral lip of ostium very short, 

 broad, strongly sclerotized. Posterior half of ductus bursae broad, 

 flattened, strongly sclerotized, preceded by a short, lightly ribbed, 

 narrower part which gives rise to the ductus seminalis from about 

 middle. 



Type: Masatierra: Cerro Alto, 600 m. (Feb. 1, 1952). 



Described from the unique female type. This smooth-winged, 

 virtually unmarked, species might easily be confused with a rubbed 

 or worn specimen of grisea, but the genitalia of the two are widely 

 different and enable ready identification. The long, stout, ventral 

 lip of the ostium of grisea immediately distinguishes it from nitidis- 

 sima. The dull, brassy luster of nitidissima is also a feature that 

 distinguishes it from grisea. 



75&-910 — 65 3 



