View Image Gallery of Subfamily Plusiinae

The classification of the Plusiinae, particularly the assignment of species to genera, is at present far from stable (e.g. the papers of Dufay; McDunnough, 1942; Eichlin & Cunningham, 1978; Ichinose, 1962, 1973; Chou & Lu, 1979). It is a problem at present being studied by Dr I.J. Kitching at the BMNH and so modifications to the arrangement in the systematic account here are likely in the future. Several species have been included under Plusia sensu lato because a more precise assignment is not possible until a full morphological survey of the subfamily has been undertaken.


The subfamily is almost certainly a natural group as it can be defined by numerous characters not found elsewhere in the Noctuidae.

The forewings are triangular with a characteristic hook or falcation to the dorsum at the tornus. The forewing markings usually include a central pale, often metallic-looking maculation, either a streak or a ‘u’ and dot that can be fused to a ‘y’, sited just posterior to the cell. The ‘u’ appears to be an extension of the orbicular stigma and often grades into the antemedial. There is often a small fleck of similar pale, bright scales at the posterior end of the reniform. The venation is generally as in Fig. 15.

The thorax and anterior of the abdomen have a dorsal crest of tufts of scales that are of a similar colour to the forewings. The males usually have lateral tufts of long scales on abdominal segments 5 and 6 and sometimes on
others; these are lacking in some of the smaller species in Borneo. The counter-tympanal hood has a characteristic double structure as seen in Fig. 312 (Richards 1932). The male eighth abdominal segment is modified, usually to a high degree, but most species have a pair of eversible coremata incorporated in the sternite as in the two subfamilies already dealt with.

The male genitalia have several unique features. The overall build is slender, the valves elongate with marginal setae, sometimes a corona, and usually with a simple, slender harpe at about one third centrally and a clavus basally, lying adjacent to the juxta. The anellus is finely scobinate in most species. The saccus often bears small triangular flaps centrally, ventrally. The aedeagus has the sclerotisation of the shaft restricted to a ventral band and, except for the nigriluna Walker group, all Bornean species have the base bulbous with the ductus ejaculatorius inserted distal to the bulbosity. The vesica is usually extremely long, tubular, invested with rows of large, slender cornuti, though these are often reduced to a single apical one. There may be some correlation between the length of the vesica and the bulbosity of the basal part of the aedeagus: the vesica is relatively short and lobed in nigriluna and Plusiopalpa adrasta Felder, which have minimal bulbosity, and extremely long in ‘Plusia’ megaloba Hampson where the bulbosity is extreme. There is a disc-like or tubular structure basally in the vesica that extends down the aedeagus shaft.

No constant features were observed in the female genitalia of Bornean species and their allies that might serve to define the subfamily. The bursa copulatrix usually lacks a well defined signum but is often generally scobinate.

The antennae of both sexes are filiform in all Oriental taxa.

The larvae of Oriental Plusiinae have been studied by Gardner (1947) and Ichinose (1962, 1973). All those of Bornean species are likely to be of ‘semi-looper’ type with the first and second pairs of abdominal prolegs absent (small ones are sometimes present in early instars). The crochets on the prolegs are biordinal (two distinct sizes alternating) and the body setae are set on distinct pimples. The skin has a covering of points.

Ichinose (1962) divided Japanese species into six groups on the basis of larval chaetotaxy, but his generic assignations were rather unconventional (e.g. in Chrysodeixis Hubner); in his later paper (1973) these were more in line with other treatments in the literature. He drew attention to similarities in larval characters between Chrysodeixis and Argyrogramma Hubner, the latter including Ctenoplusia Dufay and Trichoplusia McDunnough as subgenera. The larvae are characterised by fine setal points. They are generally green with a very pale line just below the spiracles, and on each side dorsolaterally there is a broad, slightly paler band flanked by two finer ones.

Figure 15. Venation of Chrysodeixis eriosoma, showing ‘u’ and dot maculation and the augmentation of the tornal falcation by the marginal cilia on the forewing.

Chrysodeixis eriosoma Doubleday and C. acuta Walker larvae occur in two forms, with and without black dots, these dots usually consisting of two on each side per segment subdorsally, arranged obliquely, and further subspiracular spots.

Thysanoplusia Ichinose larvae have different chaetotaxy, and the skin points are large and hairlike. Though this genus was regarded as distinct from the Chrysodeixis/Argyrogramma complex by Ichinose it has been associated with Trichoplusia in Inoue et al. (1982). The former arrangement will be followed here.

The pupae of Japanese Plusiinae were described by Nakamura (1974). He found their characters homogenous, with peculiarities such as the upper position of the labrum and the rounded projection of the wings and maxillae over the abdomen that may be diagnostic for the subfamily, though the latter character is also seen in some Cuculliinae.

Nakamura described the cremaster as ‘robust, fist-like or somewhat cylindrical and rugose [fluted, grading apically to reticulate, surface ornamentation], with a pair of long hooked and apically anchor-like setae at distal end and three pairs of shorter curled setae at dorso-lateral side’, an arrangement that may also be definitive for the subfamily.

Pupation is in a loose silk cocoon in leaves.


The majority of species are herbaceous feeders; none are recorded from forest trees in Browne (1968), though CIE records show Argyrogramma signata Fabricius to feed on Eucalyptus in New Guinea. The following notes have been collated from Sevastopulo (1941), Mathur (1942), Gardner (1947), Robinson (1975), Holloway (1977), Brun & Chazeau (1980), and unpublished records kept by CIE specialists.

Perhaps the majority of species will prove to be polyphagous but restricted to herbaceous vegetation in disturbed habitats in the tropics, a category which includes agricultural crops. Several species such as Chrysodeixis eriosoma and Thysanoplusia orichalcea Fabricius, are recognised pests and are characteristically widespread geographically, highly dispersive (recorded as migrants) and usually captured in open habitats.

The only strong indication of specificity is for Anadevidia peponis Fabricius, widespread in the Indo-Australian tropics but not taken as yet in Borneo. It appears to be restricted to the family Cucurbitaceae.

Most records of Ctenoplusia albostriata Bremer & Grey are from the family Compositae. Support for regarding C. vittata Wallengren (Africa) as sister-species to albostriata is provided by the record by Pinhey (1975; as transfixa Walker) of a larval host in the Compositae.

Records for other species will be given in the systematic section.


The subfamily shows a fairly even distribution of diversity throughout the world except at very high latitudes.

Just over half the Bornean species are found throughout the Indo-Australian tropics, some extending to the African tropics or having close relatives there.; Many also extend into the subtropics and migrate into temperate zones. These widespread taxa are: Chrysodeixis eriosoma, C. illuminata Robinson, Argyrogramma signata, Thysanoplusia orichalcea, Ctenoplusia albostriata, Plusiopalpa adrasta, Zonoplusia ochreata, ‘Plusia’ lectula Walker and Dactyloplusia impulsa Walker. The last three appear to be rare in Australasia.

‘Plusia’ nigriluna is widespread in the Oriental tropics and is replaced by a sister-species or complex in the Australasian tropics. The minutus Dufay group of Chrysodeixis includes an allopatric array of species extending through the Indo-Australian tropics to New Guinea, but the diehli Dufay/ plesiostes Dufay pair is more or less restricted to Sundaland. Another widespread, largely allopatric complex of species is seen in the Ctenoplusia tarassota Hampson/sigillata Dufay group of species, which also extends to New Guinea.

Thysanoplusia bipartita Snellen is shared between Borneo and Sulawesi and fills a geographical gap between T. intermixta Warren and T. ekeikei Bethune-Baker but is sufficiently different from those two to cast doubts on the hypothesis that the three taxa are vicariant products of a widely distributed ancestral species.

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