The genital segments and internal genitalia of Agathiphaga vitiensis are described. Sternum VIII is anteriorly produced into blunt paired apophyses and posteriorly into a tongue-shaped lobe. Segment IX is a complete ring, very short in the dorsal and ventral midlines; its anterolateral lobes are largely apodemal. The long and curved gonopod ("valva") consists of a single piece. There is no median sclerite between the gonopod bases, but an open, softwalled "subgenital crypt" below the entrance of the phallocrypt may be homologous with the "median plate" in other primitive homoneurous moths. Tergum X bears a pair of broad "superior lobes" and the postgenital complex terminates in a medially intended, sclerotized "terminal lobe" above the eversible perianal area. The roof of the posterior part of the genital chamber bears a median aggregation of cuticular spines (the "spiny plate"), and a pair of smooth lateral sclerotizations ("presocii") tentatively attributed to venter X: a pair of setose sclerites (socii) are tentatively attributed to the paraprocts. The area bearing the spiny plate and presocii may in repose be folded down behind the phallus, thereby closing the phallocrypt. The phallus comprises a tubular phallotheca and an eversible aedeagus; the thick basal margen of the phallotheca is posteriorly expanded and forms the floor of the greater part of the phallocrypt; there is no ventral aedeagal branch. The musculature comprises two IX/X muscles, a segment IX muscle inserting on the subgenital crypt, phallic pro- and retractors (the former originating in the gonopod), intrinsic phallic muscles, a single segment IX muscle (adductor) to the gonopod and five intrinsic muscles of the postgenital complex. Each testis comprises four large, separate follicles. The spermatozoa do not remain grouped in discrete bundles in the vas deferens. Seminal vesicles are located on the vasa deferentia close to the testis and are doubtfully homologous with the vesicles in other Lepidoptera. The unpaired ejaculatory duct is very short. The evidence bearing on a reconstruction of the ground plan of the lepidopteran male genitalia is reviewed. Segment VIII was similar to the preceding segments. It is tentatively suggested that tergum and sternum IX were fused, that the gonopod was undivided and that a tubular, partly sclerotized aedeagus was present; deviations from these states within the order are therefore considered to be autapomorphic. The base of the aedeagus was probably surrounded by a short, collarlike phallotheca. It is suggested that there was a median sclerite between the gonopod bases, but the presence of discrete, paired and muscular "valvellae" in the lepidopteran ground plan is considered doubtful. It is further suggested that dorsum X bore a pair of lobes and that there were paired sclerotizations in venter X. The X/XI boundary is very difficult to trace. Seventeen muscle sets are ascribed to the lepidopteran ground plan; it is considered an autapomorphy of this ground plan that the phallic protractor originates within the gonopod. The testes presumably had large, separate follicles and there may have been two pairs of tubular accessory glands. The testes and the double set of accessory glands of Agathiphaga could be cited in support of a sistergroup relationship to all other Lepidoptera whereas the phallic structure (and possibly the "spiny plate") might support a sister group relationship to the Heterobathmiina. There is no support in male genital structure for a sistergroup relationship to the Heterobathmiina + Glossata; the latter phylogenetic hypothesis may be preferable on other grounds, however.
The skeletomuscular anatomy of the male genital segments of E. pardella is described. The anteroventrally produced segment IX ring and bilobed tergum X are attributed to the ground plan of the Sabatinca group of genera. The gonopod base bears a prominent dorsomedian process. Posterolateral sclerotizations in the anal cone wall are unusually strong, venter X plates are simple and weakly sclerotized. The phallus comprises a double-walled phallobase and a single-walled aedeagus which is divided into a dorsal and a ventral branch; the gonopore opens distally on the latter. Close-set radial folds around the gonopore are a probable micropterigid autapomorphy. Fibres of a VIII/IX dorsolongitudinal muscle sometimes insert in the gonopod base. The phallic protractor originates in the gonopod. No muscles from the segment IX ring insert in the gonopod; a similar condition is found in Paramartyria. Gonopod adduction is apparently effected by a muscle inserting on a median plate between the gonopod bases. A powerful depressor of the postgenital complex originates posterolateral by the segment IX ring. The genital musculature in Epimartyria is compared with that in Micropterix and Eriocrania, and the bearing of genital structure on the systematic placement of Epimartyria is discussed.
The monobasic Colombian genus Osrhoes is redescribed on the basis of the male holotype and a female paratype of O. coronta Druce, 1900. Osrhoes is unique among the exoporian moths so far known in having a long internal duct from the ductus bursae to a chamber adjacent to the ovipore, a functional analogy of the 'ductus seminalis' of ditrysian Lepidoptera; the subgenital plates are very large and completely fused in the midline, i.e., there is no 'intergenital cleft'. Strong reasons for retaining Osrhoes in the non-ditrysian grade are the homoneurous venation and large forewing jugal lobe, while apomorphies supporting its assignment to the Exoporia-Hepialoidea include, e.g. its elongate intercalary sclerite, postapical Rs3, male genitalia with typical hepialoid hinged juxta/trulleum complex and lack of sclerotized phallus. The absence of inter-M crossveins and the extreme reduction of the maxillae are currently considered diagnostic traits of the family Palaeosetidae, which is otherwise represented by three small Australasian genera. The wing proportions and absence of a forewing 'anal loop' in Osrhoes probably also indicate relationships to palaeosetids. Although the status of the crossvein character as an apomorphy is debatable, it is preferred at present to uphold the tentative àssignment of Osrhoes to the Palaeosetidae.
The basic divisions of the family Micropterigidae are discussed. Hypomartyria micropteroides n.gen., n.sp. from Osorno province, Chile, and Squamicornia aequatoriella n.gen., n.sp. from Napo province, Ecuador, are described; they are the first genuine micropterigids recorded from South America. The new taxa are assigned to the Sabatinca-group of genera, and their cladistic relations within the group are tentatively assessed. Hypomartyria appears to be derived from an ancestor closely similar to that of the entire group. Squamicornia exhibits some possible synapomorphies with Old World southern hemisphere taxa. There is no evidence that the two South American genera are each other's closest relatives.
Agathiphaga moths lack microtrichiation on most of the fore-wing upperside (apart from a basal anterior area), while it well developed on the hind-wing upperside and on the underside of both wing pairs. Scales on the fore-wing upperside largely occur in clusters, which then often comprise one larger, notched/truncate and pigmented 'cover' scale, and one or more smaller, weakly pigmented/unpigmented, smoothly rounded 'ground' scale. The former scale type proved to be hollow and have trabeculae in the inner lumen. However, it has no perforations in the abwing lamella; hence the absence of such perforations (ore even vestiges thereof, in the form of small depressions) from a scale is not necessarily indicative that it is of the solid type. The ground scales, like all hind-wing and underside scales, are of the commonplace solid type which is of general occurrence in non-glossatan moths. Evolutionary aspects of scale morphology in basal moths are discussed. The origin of hollow wing-surface scales cannot have been a single, unreversed event, but independent evolution of this scale types in the Agathiphagidae and the Coelolepida (= Acanthopteroctetidae + Lophocoronidae + Myoglossata) remains the most parsimonious assumption.