Synonyms and other taxonomic changes
Diatraea evanescens (Dyar, 1917); Diatraea sobrinalis
Size
10 to 20 mm long. Large in southern U.S., smaller in the north.
Identification
Introduced into Florida from Brazil in 1914. Has spread north. Not cold-hardy but can take light frost.
Head: Large eyes, no hair. Palpi very long, beak-like, 2 to 3 times longer than head.
Antenna: Simple, reaching to mid wing.
Wings:
Forewing: Pale brownish on female; light tannish on male. Rounded discal spot at mid wing in center. Forewing veins are brown, flanked by narrow pale edging; streaks in the middle of the intervenal spaces are brown. (This is the opposite of genera like Eoreuma). Dark dots usually present at base of fringe and are situated at the ends of the brown intervenal streaks. Fringe the same color as wings.
Hindwing: White, slightly more brownish on male.
Legs: The legs are moderately stout, cream.
Abdomen: White. Male has a pair of lateral tufts on second segment. Segments 2 and 3 more reddish-brown on male.
Range
Across southern U.S., also Ohio, Maryland. Canada: Ontario.
Possibly a migrator to north during the summer. Not cold hardy.
Season
April to September in south. Probably June to Aug in north.
Food
Assumed to feed on Slender Paspalum Paspalum setaceum in northern U.S. and southern Canada. It is the only Paspalum species available in Ontario, listed as rare. Common names of Paspalumare Dallisgrass, Sticky Heads or Argentine Bahia grass in southern U.S. Very similar to crabgrass, grows to 40 inches (100 cm) tall. Note: Paspalum is also used by the Clouded Skipper Lerema accius in the south.
Life Cycle
Larva bore inside grass shoots, particularly ones with seed heads. Larva are thin with strong tubercles. Prolegs hooked. Segments 8 and 9 are plated. Pupa cylindrical, top end square. Tongue short.
Internet References
Cornell University Memoirs Agriculture Experimental Station, 1923, #68: The Lepidoptera of New York and Neighboring States by Forbes pg. 590. General information on Diatraea species.
Entomological Americana, 1888, Vol. 4, pg. 119 by Fernald. General information on Diatraea species.
Insecutor Inscitiae Menstruus, 1917, Vol. 5 #4-6: Seven New Crambids from the U.S. by Dyar, pp. 84 to 85 – Diatraea evanescens.
Proceedings of the Entomological Society of Washington, 1922, Vol. 24, #6 by Schaus, pg. 140. Diatraea sobrinalis.
Proceedings of the United States National Museum, 1928, Vol. 71 Article #19: American Moths Diatraea and allies by Dyar and Heinrich.
