H. unipunctata is very difficult to differentiate from H. piniata. The range of variation in these two species is extraordinary, making most characters unreliable.
McGuffin (1977) provides the following concise, if rather dubious, key: 1. Wings brownish in subterminal area ............................ unipunctata
-- Wings not brownish in subterminal area ............................... piniata
The best way to differentiate these two species is by the white spot on the FW--unipunctata almost always has a large, roundish spot, whereas piniata usually has a small, irregular-shaped or indistinct spot (Covell 1984).
unipunctata has more color variation than piniata--piniata never has orangish shading, unipunctata can be either way (Covell 1984, McGuffin 1977).
WING SHAPE Supposedly, the HW is more scalloped in unipunctata (McGuffin 1977), though this is not relaible.
FOOD PLANT piniata feeds on conifers, unipunctata on deciduous (McGuffin 1977).
H. esther is always dark purple/orange and much less mottled.
TAXONOMY NOTE: This genus has been moved around between tribes several times: Forbes (1948) placed it in Melanolophiini, but it was moved to Boarmiini by McGuffin (1977). Hodges et al (1983) moved it to Bistonini. Rindge (1985) moved it back to Boarmiini, where it is for now.
Distribution pattern: Eastern?
Reilly pers obs
Reilly pers obs
Forbes WTM. 1948. Lepidoptera of New York and neighboring states: part II. Cornell University Agricultural Experiment Station memoir 274.
McGuffin WC. 1977. Guide to the Geometridae of Canada (Lepidoptera) II. Subfamily Ennominae. 2. Memoirs of the Entomological Society of Canada 101: 1-125.