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The tribe Hypochrosini derives from the Hypochrosidae of Guenée (1857)
and has priority over the Anagogini of Forbes (1948). The type species for the
Anagogini is Anagoga pulveraria Linnaeus. The tribe was defined by Forbes
(1948) within his group of tribes with a pupal cremaster ending in eight hooked
setae. The characters he referred to are: a pupa with callosity, without flange-
plates; male genitalia with a double furca, the left arm usually longer than the
right; gnathus with a vertically elongate, blade-like tip, usually with a single
series of spines; male antennae pectinate, various. The genus Hypochrosis Guenée,
type genus of the Hypochrosini, shares (not all species, see Hypochrosis
Guenée) the furca
character that provides the most reliable definition for the tribe.
In South-east Asia the tribe is more diverse than in North America,
hence it is possible to survey the validity of these features more widely. The
furca is the most reliable feature, though secondarily lost in some taxa. The
vinculum is slender, without a saccus, but looping down on each side to a
variable extent from a central point of fusion with the valve bases (also fused
together). The loops each contain a single corema, rarely a double one (Mesaster
Warren) or none (Anagoga Hübner). The uncus is usually
dorsolaterally flattened, often apically spatulate; there are digitate, setose
socii associated with it as seen in some other ennomine tribes. The aedeagus
shaft terminates asymmetrically, usually acutely; vesica ornamentation is very
variable. The comb of setae on male sternite 3 is not present.
The female genitalia are typical of the subfamily, with the ductus bursa
often sclerotised and fluted. The signum varies but in many cases is a typical
centrally stalked disc bearing spines.
The moths are often brightly coloured and strikingly patterned, though
without satiny scales as in some other tribes.
The tribe Scardamiini may be related (See
Scardamiini).
Forbes (1948) divided his Anagogini into two subtribes on the basis of
male antennal characters, presence or absence of coremata in combination with
gnathus spines in a row versus diffuse, and presence or absence of pupal
grooves. The combinations of genitalic characters do not hold for the Oriental
fauna, and genera without pectinate antennae in the male occur. Therefore no
attempt has been made to apply these subtribes here.
The Hypochrosini show some indication of host-plant specialisation in
genera where several taxa have been reared. The probable sister-genera Fascellina
Walker and Corymica Walker feed on Lauraceae. Heterolocha Lederer
species are known mainly from Caprifoliaceae. The few records for Achrosis Guenée
are from Rubiaceae. Garaeus Moore species are known to feed on several
plant families.
The tribe is one of three geometrid groups where lachryphagy (mammalian
tear sucking) is extensively recorded, the others being the Macariini (See
Macariini) and the Scopula/Zythos group of genera in the Scopulini (Bänziger,
1973, 1983, 1988). Lachryphagous hypochrosine genera noted by Bänziger are Hypochrosis
Guenée, Achrosis Guenée and Fascellina. These geometrid
groups are also noted to come to carrion bait in Borneo (Holloway, 1989).
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