Noctuidae - Agaristinae

 

 

Euscirrhopterus cosyra (Druce)

Euthisanotia cosyra Druce, 1896, Biologia Centrali- Americana. Insecta. Lepidoptera-Heterocera, 2:328, pl. 70, fig. 4.

Diagnosis: Eucirrhopterus cosyra is superficially like gloveri, with the same gray-brown forewing coloration with a broad white stripe from the base, through the cell and angled upward to the costal margin. The major superficial difference between the two species is the absence of orbicular and reniform marks in cosyra in contrast to the distinct marks in gloveri. Euscirrhopterus cosyra, as in gloveri, is not sexually dimorphic and both males and females have the basic female coloration of the genus. The white forewing band has a very sharp, inwardly curving, angulation at the position of the reniform (if a reniform were present). The outer margin of the white band from this angulation to the costal margin is accented with black and the margin is not scalloped as in gloveri. Another excellent feature separating the two species is the frontal process. The frontal process is round with an other ring in cosyra, but shaped like a highly protuberant blade-shaped structure with a tridentate outer margin in gloveri. The hindwing of cosyra is similar to that of gloveri, but a discal dot is absent and the yellow spot in the anal angle of gloveri is, instead, a longer, thin line.

Distribution (See Map on Left): Euscirrhopterus cosyra has a slightly more restricted distribution than that of gloveri, but is generally sympatric with it in most of its range. The species has been collected in most of southern and western Texas, southern, New Mexico, and southern and central Texas. Euscirrhopterus cosyra also occurs in most of northern Mexico and has also been collected in Baja California del Sur. There is no discernable geographic variation in the species. Males are slightly smaller than females.

Adults have been collected from May to October, although the majority appear to have been taken in July.

Identification Quality: Excellent

Larva: The larva has been described by Kunze (1906) and Crumb (1956). Euscirrhopterus cosyra lacks the lateral dorsal-ventral stripes and orange patches of gloveri. Instead cosyra has a complicated pattern of gray spots and pale white lines. Each gray spot is the pinaculum of a setae and each is surrounded by a light, dull white ring. The largest gray spots on abdominal segments one through eight are associated with the setae D1 and SD1. An interrupted dull white subspiracular line is present as is a distinct subdorsal line. The dull white regions surrounding the pinacula around the spiracle tend to be irregular and confluent forming irregular patches of dull white. The head is dull yellow with a brown reticulation. The larva pupates in a earthen cell, but the cell is round or ovate, not long and tubular as in gloveri.

Foodplants: Kunze (1906) records the larva from the "young, tender joints" of Opuntia arbuscula (Cactaceae) and Crumb lists "Opuntia" and "giant tarajillo" which he interpets as the saguaro Cereus gigantea (Cactaceae). Some adults from Val Verde County in Texas were reared from Opuntia leptocaulis (Cactaceae).

Euscirrhopterus cosyra

Euscirrhopterus gloveri and poeyi are easily distinguished from cosyra by the absence of a distinct reniform and orbicular in cosyra.

Similar Species

Euscirrhopterus gloveri

Euscirrhopterus poeyi (female)