Noctuidae - Psaphidinae - Grotellini

 

 

Grotella citronella Barnes and McDunnough 1916

Grotella citronella Barnes and McDunnough, 1916, Contrib. Nat. Hist. Lep. N. Am., 3(1): 5, pl. 3, figure 13 adult.

Diagnosis: Grotella citronella appears looks like a yellowish version of mcdunnoughi, a species with which it is sympatric in the Mohave Desert regions of southern California. The forewing is yellow cream in color, but the yellow is much stronger and individuals are never dusted with adobe brown as are many individuals of mcdunnoughi. This yellow-cream forewing is often overlain with a slightly grayish film. The antemedial and postmedial forewing lines are almost always present and represented by a series of ill-defined black dots. The reniform mark may be present a a slightly lighter streak. The hindwing is almost always suffused with dull gray-brown. Wing length: mean = 9.20 mm, standard deviation = 0.77 mm, n = 10.

Adults fly in April and May.

Distribution: Grotella citronella is found in the Mohave Desert region of southern California and extreme southwestern Arizona. The species occurs from southeastern Imperial county in the south to Inyo county in the north. Although specimens are relatively rare in collections compared to mcdunnoughi, there appears to be a fair amount of variability among individuals in the amount of gray wash over the forewing. Some individuals are almost bright yellow, while others are considereably darker, particularly along the outer forewing margin.

Identification Quality: Excellent

Larva: Unknown

Foodplants: Unknown

 

Grotella citronella

The best structure to separate this species from mcdunnoughi in addition to the stronger yellowish tinge of citronella is the shape of the central protuberance of the frontal process. The central protuberance is a laterally compressed, blade-shaped structure in mcdunnoughi. The central protuberance is similarly shaped in citronella, but the outer margin clearly retains a circular structure and is not a sharp edge as in mcdunnoughi. The seventh tergum of the male and female abdomens is modified with the caudal margin constricted and heavily sclerotized, forming a knob-like structure. This modification of the seventh tergum can usually be seen by carefully brushing away the scales from the apex of the abdomen. This modification is absent in the two species of the spaldingi species group.

Similar Species

Grotella mcdunnoughi

Grotella spaldingi