Synonyms and other taxonomic changes
Plagiometriona is considered a synomyn of
Helocassis in
Cassidinae of the world - an interactive manual Numbers
1 species (
clavata) north of Mexico
(1)
2 subspecies (
clavata, testudinaria) north of Mexico
(1)
the latter is considered a separate species (
Helocassis testudinaria) by Lech Borowiec in Cassidinae of the world - an interactive manual
Identification
most noticeable feature in adult, covering much of the carapace, is a dark brown irregular patch shaped like a teddy bear, with the front and back "legs" of the "bear" extending to the outer margins of the elytra, and the "head" of the "bear" extending onto the pronotum
in
clavata, the "legs" and "head" of the "bear" are as dark as its "body", whereas in
testudinaria, these extremities seem slightly paler than the "body" but I'm not sure whether this is a reliable difference [RM]
Range
P. c. clavata: eastern two-thirds of United States and southeastern Canada
(1)
P. clavata testudinaria: AZ, LA, NM, TX
(1) Season
April to October in North Carolina
(2)Food
larvae and adults feed on plants in the tomato family (Solanaceae) such as nightshade and horse-nettle (
Solanum spp.), ground-cherries (
Physalis spp.), and Jimsonweed (
Datura stramonium)
(3)See Also
Deloyala species of tortoise beetles are superficially similar but the "teddy bear" shape on their carapace is missing "hind legs"
Internet References
species list with links to info on synonyms, host plants, distribution, and images of prserved adults (Lech Borowiec and Jolanta Wietojanska, Cassidinae of the world - an interactive manual)
distribution in Canada - PDF doc (Chrysomelidae, in: Checklist of the Beetles of Canada & Alaska)