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Cania Walker
Type species: bilinea Walker
The genus has venation (Fig. 35) and palps as in Narosa but the antennae
of the male are broadly bipectinate over the basal two-thirds. Female forewing
facies usually consists of two subparallel, oblique fasciae on a generally fawn
ground. Males in one lineage, the bilinea group, are patterned as in the
female, but in other lineages there is a greater or lesser degree of sexual
dimorphism. The forewings of both sexes are relatively broad.
Figure 35.
Wing venation of Limacodidae. 35, Cania bandura
In the female genitalia (except minuta sp. n.) the ovipositor
lobes are more densely setose than in other genera; this is most extreme in the bandura
group. The genus is characterised by the presence of a transverse,
sclerotised exterior flap just posterior to the ostium bursae, though this is
reduced and modified in the bandura group, and bifid, setose in minuta.
Most lineages lack a signum in the bursa, but in some of the bilinea group
there is a single, weakly scobinate, disc-like signum; some of the bilinea group
also have a sclerotised, distally spiralled ductus bursae.
In the male genitalia the uncus is generally broad and at least bifid;
the aedeagus vesica contains cornuti. Otherwise the structure is very variable
and provides features diagnostic for the four lineages recognised here; three of
these are represented in Borneo.
The bilinea group has been mentioned already. The uncus has a
central lobe with long setae and lateral socii with finer, shorter ones. The
tegumen is broad. The gnathus is well developed, terminally massive, bifid or
square. The valves are split into a slender dorsal arm and a broader ventral
process that is notched or lobed diagnostically. The juxta or anellus extends in
a complex series of 'brain-like' folds back into the abdomen. The aedeagus
vesica has one distal cornutus (seen basally in the aedeagus when not everted).
The bilinea group is most diverse in China; the taxon robusta Hering
(= pallida Hering syn. )probably represents a good species (C. hatita
Druce, from Hunan, may be a senior synonym of these Hering names but the
type has not been located); in Taiwan a taxon (slides 554, 555) with a most
strongly spiralled bursa that is more extreme than that of robusta (slides
546, 549, 560, 567, 674); the female of bilinea (type  dissected,
slide 552;  slides
558, 559, 562) is the least spiralled of the three. All three have a
longitudinal band of scobination at the apex of the aedeagus. A further taxon (slide 524) has a slender, unangled ventral arm of the valve; no
females have been located. In addition there are three taxa without a spiral in
the ductus bursae. Two are undescribed, one in the N.E. Himalaya (slides 550,
556), one in Java and Bali (slides 525, 544, 545, 548, 563, 564). The latter is
probably the sister species of striola Hering, the representative of the
group found in Borneo. A single male of a species allied to bilinea has
been taken in the Philippines (Mindanao).
Life history data are available for two of the group, bandura and
the undescribed species from Java. The taxon bicarinatus Walker, placed
as synonym of bilinea, was described as a hemipteran in the genus Aspidiotus,
based on a dried specimen of the larva!
A larva attributed to robusta but probably that of bandura was
described and illustrate by Wood (1968). It is medium to dark green, elongate,
somewhat ovate, with complete rows of spined processes, the laterals longer than
the subdorsals; there are rows of pale blue spots and a complex pale blue
‘face and shoulder’ pattern centrally, extending across the width. The
lateral processes are paler, somewhat pinkish buff. The host-plant recorded was Cocos
(Palmae).
The Javan species was described by Horsfield & Moore (1859) and by
Piepers & Snellen (1900) the latter authors casting doubt on the accuracy of
the illustration by the former. The larva is oval in form, surrounded by
prominent lateral rows of tubercles. It is usually dark green. Many little dark
dots, some circled blood red, or completely red dots, or dots the colour of
leather, sometimes also yellow ones, flank and invest a dorsal yellow or yellow
and black band. The host-plant was Musa (Musaceae).
A new species, minuta, is described below and represents a
distinct lineage with characteristics as indicated. Sexual dimorphism is slight
only.
A third lineage, possibly sister group to the fourth, sharing an
elongate saccus in the male genitalia and strong sexual dimorphism, is
restricted to the Indian subregion and consists of the taxa mollis Walker,
sericea Walker, pulligonis Swinhoe and obliquifascia Hampson.
The exact status of these taxa relative to each other requires investigation but
none are subordinate to bilinea or represented in Sundaland; the
literature is confusing due to the hazards of identification in the genus. All
types in this group have been examined.
In the male genitalia the uncus is weakly bifid, the valves oval to
upwardly curved, reniform, unornamented, and the elongate vesica of the aedeagus
has a very long row of cornuti running along it.
Bell (MS) described the larva of pulligonis. It is a flattened
semi-ovoid with a row of very short, circular raised spots as tubercles
dorsolaterally, each with five or six green, white-tipped spines; there is a
lateral row of elongated, conical spined tubercles directed out horizontally.
The colour is grass green with a thin, light yellow, dorsal band. The larva
lives on the under-side of a leaf, an oldish one for preference, eating from the
midrib. The cocoon is often in a rolled leaf, ovoid, hard, dark brown, covered
by a dense tent of greyish silk attached to the surrounding leaves or to the
walls of a crevice wherever it occurs. The host-plants recorded were Ziziphus
(Rhamnaceae), Terminalia (Combretaceae) and Careya (Barringtoniaceae).
The fourth (bandura) group shows the most extreme sexual
dimorphism containing a trio of species with the male forewing a glossy, dark
greenish brown with a narrow fawn margin. Recognition of this extreme sexual
dimorphism was somewhat tentative until the disparate sexes were reared from the
same batch of larvae. The nomenclature for the group is based on both sexes so
the synonymy presented in the accounts of the three species, all Bornean, is
tentative.
Sister to this group, and somewhat transitional in characteristics
between the mollis group and the trio just described, is siamensis Tams.
The species was based on a single female; males associated with it here are also
from Thailand (slide 671) and have forewing fasciae following a similar course,
the curved submarginal being associated with an indistinct row of white dots.
The male has the rather rounded forewings of the bandura group but the
dark zone is replaced by a speckled area delineated distally by a curved,
slightly darker fascia and crossed by an irregular oblique medial fascia similar
to that in mollis group males. The female is much larger, the forewings a
medium ochreous brown, uniform apart from diffuse, slightly darker fasciae in
the same position as those of the male.
In the male genitalia the valves are somewhat reniform as in the
previous group but much deeper, the uncus similarly bifid, the gnathus more
massive, tending towards the bandura trio. A triangular sclerotised
process, possibly a furca, occurs as in the bandura group. The aedeagus
vesica contains an oval group of about a dozen cornuti distally within it, again
perhaps a transition to the condition in the bandura group where there is
one distal cornutus.
The host-plant of one of the male specimens is given as Cocos, and
further material of both sexes recently received from Thailand was also reared
from Cocos.
In the bandura trio the male genitalia have the furca as in siamensis
but it is longer, more slender, ventrally coarsely scobinate. The uncus is
more deeply cleft, consisting of two long slender acute processes opposed by a
similarly long or slightly shorter gnathus. The valves are usually oval but
tending to be downcurved slightly rather than upcurved as in the mollis group.
In the female genitalia the post-ostial sclerotised process is broader,
less sclerotised, more scobinate. The ovipositor lobes are extremely densely
setose.
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