Species Microcrambus croesus - Hodges#5426

5426

Microcrambus croesus Bleszynski, 1967

Forewing length: 7.5 mm (1), i.e. large compared to most of the rest of the genus which have FW 5.0 to 6.5 mm.

The FWs are mostly silvery white with a dark brown curved patch on the dorsum, dark brown along the costal margin, and an oblique dark streak off the costa in the postmedian area. The subterminal line consists of a pair of (usually) obscure thin brown lines. The teriminal line is dark and continuous (not a series of dots).

Western, central and southern Texas; Florida; Mexico. (2), (3), (4)

Moth Photographers Group - large map with some distribution data.

The main flight periods appear to be April-May and August-October (MPG, iNaturalist records).

Heppner (2003) reports May; August in Florida. (4)

The larval host is various grass species (Gramineae). (4)

Microcrambus elegans (left) and M. minor (right) both have much more brown shading on the FWs and the terminal line is a series of dots. Both species just barely range into E Texas, probably not overlapping with M. croesus.

Microcrambus kimballi also has the terminal line made up of dots rather than a continuous line.

Microcrambus polingi - AZ, range does not overlap.

Compare pinned specimens on Moth Photographers Group.

Microcrambus croesus Bleszynski, 1967. Studies on the Crambinae (Lepidoptera). Part 44. New Neotropical Genera and Species. Acta Zoologica Cracoviensia. 12:88(1)

[The above-linked pdf of Bleszynski's paper is oddly formatted; it starts with p. 100 part way through his "Preliminary Checklist of Neotropical Crambidae", then has a series of grayscale plates (low quality), then finally back to the beginning of the article (p. 40), thence with the remainder of the article through text p. 99. As noted in the citation above, the description of M. croesus is on p. 88.]

Moth Photographers Group