Epidesmiinae Murillo-Ramos, Brehm & Sihvonen 2019
Creators: name: Murillo-Ramos, Leidys
name: Friedrich, Egbert
name: Williams, Steve
name: Wahlberg, Niklas
name: Brehm, Gunnar
name: Sihvonen, Pasi
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Geometridae

description: GENERAL DESCRIPTION OF EPIDESMIINAE
Head and thorax (Figs 1, 6–15)
Antennae unipectinate in males, shorter towards the apex (bipectinate in 2/5 Adeixis species and Arcina); filiform in females (shortly bipectinate in Systatica and Abraxaphantes). Labial palps elongated, second segment longest (less pronounced in Systatica); vom Raths’s organ an elliptical invagination. Frons elongated in many species. Chaetosemata small. Tegula large. Epiphysis small. Spur formula in male and female tibia 0–2–4 (hind leg with 2 + 2 spurs). Male hindleg hair-pencil absent (present in Phrataria replicataria Walker, 1866). Metathorax furca with well-developed apophyses; anterior and basal ventral laminas separate.
Abdomen (Figs 1, 6–15)
Abdomen slender. Tympanal organs large, almost meeting medially in a few species; tympanal organs approaching 45° angle relative to the abdomen; the posteromedial corner with narrow sclerotizations that extend into second sternite (pronounced in Abraxaphantes and Epidesmia). Ansa shape variable, ranging from evenly tapering and narrow rod to bottle-shaped with pickaxe-shaped apex. Second sternite often distinctly sclerotized, in few species with sternotympanal process with free end curved over tympanum (Figs 6, 14). Abdominal sternites and tergites of both sexes undifferentiated, with few exceptions (e.g. posterior margin of male eighth sternite bilobed and setose in Epidesmia tricolor). Male third sternite with a row of setae in few species (Epidesmia, Dichromodes).
Wings (Figs 1, 2, 4, 5)
Pattern, size and shape variable (Fig. 1). Colour varies from different shades of brown to yellowish, grey and white. Wingspan from 20 to 70 mm. Forewing outer margin distinctly convex (Ecphyas and Systatica), weakly convex or concave. Forewing apex acute or rounded. Forewing venation: two areoles formed by R + Rs1–4; Rs1–Rs3 often stalked; cross-veins between M1 and M3 reduced, weakly tubular. CuA1 not stalked with M3. Hindwing venation: Sc + R1 parallel for long-distance with Rs; cross-veins between M1 and M3 reduced, weakly tubular. M2 tubular. One tubular A vein. Frenulum small. Resting posture of wings varies from planiform (for instance Systatica) to tectiform (for instance Phrixocomes) and potentially veliform (the latter is supported by a distinctly coloured underside and frequent observations of specimens with the wings partly or fully vertically folded over the abdomen in Phrataria) (Fig. 2).
Male genitalia (Figs 6–15)
Uncus long, narrow (short in Ecphyas). Socii minute, setose (reduced, barely recognizable in Adeixis). Gnathos distinct, arms fused, apically granulate, spinose or dentate. Tegumen narrow. Opened valvae upright (but nearly horizontal in Dichromodes), mobile (fused in Ecphyas), setose ventrally, with narrow or round projections (absent in Systatica and Phrataria, and projections present or absent in Dichromodes). Juxta variable, often sclerotized and bifurcate. Vinculum narrow. Transtilla often with two large, sclerotized, triangular lobes laterally, arms weakly sclerotized or membranous medially, barely fused. Saccus round (angled in Systatica). Coremata absent. Aedeagus variable, cornutus single (two cornuti in Dichromodes confluaria, D. euscia and D. stilbiata C. Byrne, pers. comm.) or absent, vesica surface often covered with sclerotized granules. Vesica large, with diverticula.
Female genitalia (Figs 6–15)
Two signa (in 5/9 genera), one stellate or granulate wide plate, another long, granulate or spinose narrow plate, both in mid-part of corpus bursae either ventrally or laterally; or one stellate or irregular-shaped signum (in 4/9 genera) in mid-part of corpus bursae either ventrally or laterally. Corpus bursae pyriform or constricted and narrower before anterior end, posterior part with sclerotized striations (in 5/9 genera). Ductus bursae length and degree of sclerotization variable. Shape and degree of sclerotization of lamella antevaginalis and lamella postvaginalis variable. Papillae anales round or weakly elongated, setose.
Morphology of individual Epidesmiinae genera (Figs 6–15)
Morphology of each genus was studied using the type species, and in species-rich genera other material was studied also. We are aware that as more material is examined, in particular in Dichromodes, we will gain a more accurate understanding of variation within each genus. Therefore, we do not provide detailed descriptions of genera, but instead illustrate relevant morphological structures in the colour plates provided. Selected structures are highlighted with arrows. The highest variation in the morphological structures are found in wing pattern and size; the number, position and shape of signa; shape of corpus bursae and its sclerotizations; tympanal organs; valva shape and its ornamentations; and in labial palps. Variation and similarities in these are useful in diagnosing the Epidesmiinae genera, and other groups within Epidesmiinae, for instance, if a tribelevel classification within the subfamily is needed later. The morphological variation should be compared against the molecular phylogenetic hypothesis of Epidesmiinae (Murillo-Ramos et al., 2019) to see if correlations exist.
Distribution, biology and immature stages (Fig. 3)
Epidesmiinae have an Australasian distribution with species recorded from Australia, New Zealand, New Caledonia and eastern Papua New Guinea. Monotypic Abraxaphantes is the only Indo- Malayan representative, recorded from Thailand and southern China. Dichromodes is the most diverse genus with 67 described species (Scoble & H a u s m a n n, 2 0 0 7), b u t p o t e n t i a l l y o v e r 2 0 0 additional species await description (Marriott, 2012). Several species fly commonly during the day and fly a short distance when disturbed in heath and grassy areas, but are also attracted to light during the night (Marriott, 2012). Little information is available on immature stages. Eggs are laid singly by Phrataria bijugata (Walker, 1863) and Epidesmia hypenaria (Guenée, 1857). Those are turquoise blue when laid and darken as they develop. The first instar larva of P. bijugata is faint pink, and its abdomen is curved when resting. Epidesmia tricolor larvae have been recorded feeding on tea tree (Leptospermum J.R.Forst. & G.Forst.; Myrtaceae) (Scoble, 1999) and Dichromodes have been reared on Eucalyptus L’Hér. (also Myrtaceae). Dichromodes larvae are characteristically long and thin, and camouflaged to resemble small dead twigs of the hosts. Dichromodes anelictis Meyrick, 1890 showed high host specificity and was successfully reared on Eucalyptus viridis R.T.Baker (green mallee). This moth occurs in autumn and can be prevalent at that time in ‘mallee areas’ but is absent in different habitats. In contrast, the larva of Epidesmia chilonaria is polyphagous and was easily raised on Eucalyptus melliodora A.Cunn. ex Schauer and that of Epidesmia hypenaria fed on Eucalyptus camaldulensis Dehnh. (river red gum) and Eucalyptus macrorhyncha F. Muell. ex Benth. (red stringybark). Small and fully grown larvae of Ep. chilonaria are shown in Figure 3E, F. Larvae of P. bijugata, shown in Figure 3B, proved difficult to rear and it took several attempts to identify host preferences. Feeding was eventually observed on Eucalyptus polyanthemos Schauer and Eu. melliodora, where leaves were skeletonized from the edge. These larvae did not survive beyond the second instar, probably indicating that the preferred eucalypt host has yet to be identified. The first instar larvae of Phrixocomes hedrasticha Turner, 1936 showed some interest in a number of the local shrubs of Victoria but did not establish. The larvae of Dichromodes, Epidesmia and Phrixocomes that have been reared, show a propensity to remain rigid, stationary and often in plain sight during the day and actively feed at night.
Adeixis inostentata occurs in herbaceous marsh association in Australia, three Adeixis species were found on Baeckea -sedge maquis on sedimentary rock in New Caledonia and A. griseata occurs in characteristic ‘pakihi’ country, poorly drained acid areas with sedges and scattered low shrubs in New Zealand (Holloway, 1979). Larvae of Adeixis baeckeae Holloway, 1979 have been reared on Myrtaceae: Baeckea ericoides (Holloway, 1979). This species pupates in loosely constructed cocoons in the terminal leaves of Baeckea, and emerges about 25 days after pupation (Holloway, 1979). Structural details of pupa, such as the arrangement of cremaster setae, are not available. The habitus of Ep. chilonaria pupa is shown in Figure 3F. Adults of Epidesmia tricolor fly in or near wet forests in southeastern Australia. For more information on phenology, see Figure 17.
description: Published as part of Murillo-Ramos, Leidys, Friedrich, Egbert, Williams, Steve, Wahlberg, Niklas, Brehm, Gunnar & Sihvonen, Pasi, 2021, A morphological appraisal of the new subfamily Epidesmiinae (Lepidoptera: Geometridae) with an overview of all geometrid subfamilies, pp. 1205-1233 in Zoological Journal of the Linnean Society 193 (4) on pages 1209-1212, DOI: 10.1093/zoolinnean/zlaa189, http://zenodo.org/record/5761594