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Groupings of genera within the subfamily
Owada (1987) attempted to establish relationships between the Japanese genera. The study here of several further genera from Borneo has tended to support his system, though with recognition of a potential grouping of genera around Bertula Walker, most of which are not present in Japan. This group is treated first in the account following and is perhaps best defined by the presence of an orbicular stigma on the hindwing underside. Other characteristics include an extensively developed labial palp in the male, modification of the male forewing with a fold or flap, loss of modification of the male eighth abdominal segment, and the concentration of scobination in the corpus bursae into a signum. These features serve to associate a number of other genera with the group that show one or other of these secondary features, particularly loss of modification of the male eighth segment. Strongly developed labial palps are seen in Echanella and Oxaenanus Swinhoe outside the main Bertula group. Very many of these genera have a sheathed male foretibia, but this is also seen in the Simplicia group.
Owada (1987) noted that Japanese Bertula and the generic type species had a modification of the first tarsal segment of the male consisting of a small spur-like structure at the distal end that arises more or less at right-angles and is directed towards the tibial sheath. This feature was found to be widespread but not ubiquitous in a sample of Bornean Bertula (p. 27), and it occurs also in Isana Walker, Raphiscopa, Egnasides Hampson and Hepsidera Swinhoe, all genera that have the orbicular spot on the hindwing underside.
Owada (1987) cited Smith (1895: 78) as noting this tarsal feature in the New World herminiine genus Heterogramma Guenée (the species from Sulawesi and New Guinea included in this genus by Poole (1989) are probably all misplaced). Smith also observed it in another New World genus, Palthis Hübner. Both these genera lack an orbicular spot on the hindwing underside, and not all Bornean genera with such an orbicular spot have a tarsal spur, so the occurrence of the two characters does not overlap totally. Additionally, in Heterogramma (Fig 34) the structure of both the sheath and the tarsal spur is significantly different from that seen in the Bertula and Simplicia groups of genera. The tibial structure arises from a base that extends the length of the shortened tibia and initially narrows at an angle of about sixty degrees from the axis of the tibia before curving down towards the first tarsal segment in the form of a process that is slender and digitate rather than sheath-like. It extends to beyond the apex of a long process that is angled backwards at about thirty degrees from the apex of the first tarsal segment. This tarsal process is swollen at about one third, tapering away towards an acute and slightly sinuous apex.
The genera treated between the Bertula group and the Simplicia group in the systematic order following mostly lack a sheathed foreleg and include those regarded by Owada (1987) as primitive, such as Adrapsa and Bocana. Within this intermediate sequence are several genera where the male antennae are noded, superficially resembling several members of the Simplicia group, but these genera have less complex nodes than in the latter, where there are usually robust spines or bristles associated with the node, in addition to the broadening and flattening seen in Adrapsa, and the broadening, flattening and twisting of Hadennia.
The Simplicia group also has a sheath on the male foretibia, but this is accompanied in several genera by reduction of the tarsal segments: to three in Progonia Hampson; to one in Herminia Latreille as treated by Owada (1987), Sinarella Bryk and Hipoepa Walker. The group shows the extreme development of the obtusely angled submarginal to the hindwing and the presence of a horseshoe arrangement of sparse, coarse spines, or a pair of longitudinal fields of the same, in the corpus bursae, though this is weak in Simplicia and Sinarella, and not evident in Nodaria Guenée. In Progonia there is a pair of signa, each resembling a shuttlecock.
Table 1. Character states of the twelve characters considered to be of particular importance for relationships between the genera of Herminiinae as discussed in the text. These are listed at the bottom. ‘?’ indicates that the character state is only weakly present, and ‘±’ indicates that the character state is present in some, but not all, species in the genus. The characters and genera are ordered to indicate more clearly possible generic groupings.
- Sheath (+) or spine (S) present on the male foretibia.
- Spur present (+) at the apex of the male first foretarsal segment.
- Orbicular stigma present (+) on the hindwing underside.
- Male labial palps long, reaching to well over the thorax (+).
- Male eighth abdominal segment unmodified (+).
- Scaled flap on underside of (+) or fold within (F) male forewing.
- A distinct hair-pencil (rather than dense scaling) present (+) at junction of second and third segments of the male labial palps.
- Valves of male genitalia with spherical hair-bearing structure between their bases (+).
- Corpus bursae in female with a signum (S), two signa (2S) or scobination in a horseshoe array (H).
- Male antennae noded (+).
- Male foretarsi reduced in number, usually to one (+).
- Straight, obtusely angled hindwing submarginal present in at least some species (+).
The remaining genera in the order of treatment are included through tradition or as new, but their placement in the subfamily must be regarded as tentative and is discussed under each individually. Holloway (2005: pp. 440, 446-449) suggested that several ‘ophiderine’ genera might be herminiines. Egnasides Hampson is transferred formally on p. 53, but Ilyrgis Walker and allies need further study in this context.
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