Classification of the Superfamily Sesioidea (Lepidoptera

A forthcoming review of the Immidae, as a prelude to a revision of the family, will continue to address these questions (Heppner, in preparation b). The families that make up the Sesioidea are defined and discussed here, along with a definition of the superfamily. All new taxa and new combinations are attributed to the author of the individual family section.

The genera included here in Sesioidea were usually included in different families of the Yponomeutoidea in more recent classifications of Lepidoptera. Niculescu (1964) summarized the past associations of the Sesiidae in relation to phylogenetic aspects. The cohesion of the superfamily, in relation to the various characters available for comparison, appears healthy (see Table 1).

TABLE 1.—Family characters in Sesioidea Character

Choreutidae

Brachodidae

Extent of Evolutionary Divergence

The further divergence of Choreutidae noted above, the tendency for tortricoid wing venation, is found in several genera believed to be the most advanced within Choreutidae. The Sesiidae are so highly specialized, especially in hymenopterous mimicry, that at first it seems that this family should be the most advanced of the superfamily. However, it seems best to place Choreutidae as the overall most advanced family of Sesioidea.

Male genitalia: Variously modified, with tegumen and vinculum present; simple to complex valve; distinct uncus, gnathos, and socius present or absent; socius-like seaceous zone sometimes present; tuba analis ever prominent;. Female genitalia: Ovipositor usually unspecialized, rarely flowered; ostium bursae on the inter-segmental membrane between sternites 7 and 8, or on the sternal plate of segment 7; ductus bursae sclerotized or membranous, long or short; bulla seminalis usually small; bursa copulatrix usually ovate, occasionally modified; Signum often present, sometimes large or absent. DISCUSSION.—Major distinctions of Sesioidea include basic characters of larval and adult morphology and behavior that have been found to be useful in evaluating relationships among higher orders of Ditrysia (Heppner, 1977a).

Key to Families of Sesioidea

Wings with forewing anal margin-hindwing costal margin wing coupling;

Seta L2 directly anterior to LI on abdominal segments 1-6 (prothorax L-

Dorsum of abdominal segments 2-6 always with two rows of spines (also segment 7 in males) 2

Family BRACHODIDAE, new status

Further details of the above were noted by Heppner (1979a); however, the name was already adopted as a subfamily name by Agenjo (1966). The genitalia closely resemble those of the most ancestral sesiid genera Pennisetia (= Bembecia [auctorum]) a n d Zenodoxus. Very little is known about the bionomics of Brachodidae and the larval and pupal descriptions are based on very few species.

Most of the genera are unknown in terms of their biologies or characters of their immature stages. So far, the above information on Sagalassa is all that is known of the detailed larval morphology and chaetotaxy of Brachodidae. From the iridescent forewings of the species of this subfamily, it would appear that they are diurnal fliers as adults.

Key to Subfamilies of Brachodidae

This species has apparently been reared from the published records available (Heinemann, 1870; . Hartmann, 1880), although insufficient, and it is noted that the larvae take two years to complete their development, with pupation in the spring and adult emergence in June. The biennial larvae are interesting in relation to Sesiidae, as some sesids require 2-3 years for larval development. The less specialized sesids (Tinthiinae) are also mostly root feeders and form tubular cocoons similar to those recorded for.

Although most Brachodidae generally come from tropical regions, it is not known which specific habitats they prefer.

PHYCODINAE Heppner, new subfamily

The highly modified structures and behavior of the adults have led various researchers to consider a multitude of superficial similarities to establish relationships with other, often highly divergent, families in Ditrysia. The arrangement of the highest category defined in this paper provides, in the opinion of the authors, the first phylogenetically sound classification for sessids and is based on an apparently close ancestral relationship with the family Brachodidae. During these studies a wide range of characters were used to develop higher categories within the family, and these characters were analyzed in a wide sample of the world's sessid fauna.

As revision studies progress, a tribal classification is developed within each of the three subfamilies. As our knowledge of the world's sesiid fauna increases, it therefore seems reasonable to expect that the number of generic names will be significantly reduced. Since this feature is absent in Tinthiinae, this is clearly an apomorphic development of the more evolved sesiid subfamilies.

Key to Subfamilies of Sesiidae

Scale tuft at tip of antenna absent; forewing with veins R4 and R5 separate, or if stalked then M3 absent; hindwing with Al partially or

The presence of diffuse, linear chaetosemata (Figure 31) along the posterior margin of the head near the ocelli in all higher Sesiidae (Sesinae and Paranthreninae), and the lack of this feature in Tinthiinae, is noted here for the first time. Scanning electron microscope studies confirmed the identity of "setae" that had been suspected to be chaetosemata by conventional examination of several sesiid heads. Sesiid chaetosemata are much reduced compared to the large, conspicuous chaetosemata found in Zygaenidae and other families, but closely resemble the chaetosemata of Tortricidae, only being linear rather than more compact.

Larva with head appendages A2 posterior to A l; prothorax with L3 posterior to LI, sometimes on same pinnacle; abdominal segment 7 with 3 SV setae;. Forewing most commonly with veins R4 and R5 long stalked, stalk generally longer than xh total length of R4 or R5; CuA2 present, almost as long as CuAl. Male genitalia with valva bearing dorsally multiple scales, ventrally and apically setaceous, with open median surface or with thick, dark scales in saccular region; tegumen reduced, short; gnathos small, rounded or forked, often with tooth-like projections on ventral margin; uncus broad, elongate,.

DISTRIBUTION.—Worldwide but declining in species numbers, with most species in the eastern Oriental region. Abdomen of male with anal tuft arising from well-formed, elongate to band-like sclerites on segment 8. Hindwing with vein CuAl arising just basad of crossvein (usually obscured by scale cover); no accessory cell; Already degenerated (only line of scales remains as fold over); A2 and A3 coincide except near base; A4 present.

Female genitalia with ductus bursae long, narrow, usually membranous, sometimes partially sclerotized; ductus seminalis originates midway on ductus bursae or near ostium bursae; bursa copulatrix moderate, elongate-ovate, unmodified.

Generic Synopsis of Sesiidae

Checklist of Sesiidae Subfamily TINTHIINAE

P pemix (Leech, 1889a:592), Bembecia hirayamai Matsumura, 1931a: 1016

NL geliformis (Walker, 1856:46), Aegeria NL germaini Le Cerf, 1916b: 12

NL alboctliata (Engelhardt, 1925c:215), Synanthedon N anthracipenms (Boisduval, [1875]:392), Sesia

NL armasata (Druce, 1892:275), Aegeria [new combination]

NL pallene (Druce, 1889:80), Aegeria [new combination]

NL rubricincta (Beutenmiiller, 1909:84), Sesia

NL paimii^(Beutenmiiller, 1902:126), Sesia

Taxa Excluded from Sesiidae

Genera hereby transferred to Glyphipterigi- dae
Genera hereby transferred to Oecophoridae (Stathmopodini)
Genus excluded to Heliodinidae (transferred by Naumann, 1971)
Genera excluded to Zygaenidae (transferred by Naumann, 1971)
Species hereby excluded to Sphingidae
Species hereby excluded to Arctiidae (Ctenu- chinae)

Species hereby excluded from Sphingidae:. The type of this species has not been located and the current sphingid genus in which it belongs is also not known). DISTRIBUTION.—Of all faunal regions, with the greatest speciation in the Oriental and Australian regions for known species. DISCUSSION.—The Choreutidae are easily distinguished from other sesioid families by the basally scaled haustellum.

Meyrick and earlier workers, in deriving their estimates of phylogenetic relationships among lepidopteran families, generally did not use genital characters, or a number of basic (often internal) morphological characters, or characters of immature stages. Consequently, the combination of coreutids and glyphipterigids occurred and remained stable until recent years when comparative study of basic characters has shown that the two groups are actually unrelated (Brock. The two genera are otherwise isolated within the family and currently are the only genera of the new subfamily Brenthiinae.

Choreutis is related to the former three genera but has CuA2 of the forewing far from the end of the cell and most species lack a scale on the labial palpi. They have largely specified in the Oriental and Australian regions, but also contain a number of species in northern temperate regions. However, head morphology, wing venation and larval characters suggest that the genus is a plesiomorphic member of the Choreutinae.

Melanoxena, Rho-bonda, Tortyra, Zodia a n d Hemerophila have removed the anterior wing vein CuA2 from the distal end of the cell, while this is somewhat less pronounced in Choreutis a n d Saptha. The stems of Carduus, however, are hollow and the larvae appear to feed mainly on the inner surface of the stem. Features shared with Brachodidae and Sesiidae include the L-trisetose group of the prothorax (not Sagalassa in Brachodidae), the 2 ad-frontal setae of the head, and thin spinnerets, to name three main characters.

Several changes in the appearance and ketotaxis of choreutid larvae and juveniles appear to have occurred concurrently with the development of external feeding in the Choreutidae; Traits that may not be as important in exophagous larvae as in endophagous Brachodidae larvae have been lost and others have evolved.

Key to Subfamilies of Choreutidae

Most coreutids form typical double-walled cocoons on the surfaces of host leaves or in the leaf axils, with the cocoon having a winged inner part of white silk and an outer covering web of fine white silk. One species, Tortyra slossonia (Fernald), from Florida, feeds inside the unopened leaf buds of Ficus and forms a cocoon within the separate bud. Some genera of Choreutidae appear to have varied among particular plant families; this is summarized for the New World generation by Heppner (1977b).

The subfamily classification used below is innovative and is useful in separating genera groups now that the family is known to be distinct from the Glyphipterigidae. Larvae with heads of normal size relative to Brenthiinae, normal obliquely hypognathous with setae of medium length; abdominal segments 1–6 with SD2 closer to spiracle than SD1, same on segment 7; Dl setae closer to each other than D2 to each other; D2 in normal length segment 9;. DISTRIBUTION.-Temperate Holarctic and Pantropical areas, with extensive speciation in the Indo-Australian regions.

Generic Synopsis of Choreutidae