Metura, Walker, 1855

Beaver, Ethan P., 2020, Revision of the genus Metura (Lepidoptera: Psychidae) with description of two new species, Zootaxa 4861 (2), pp. 188-210 : 189-190

Key to Metura species

This key is built for adult male Metura , and large, late-instar larval bags, as females are undescribed for all but M. elongatus . A potential caveat with larval bags is that young individuals of at least four species incorporate leaves in the bag design before transitioning to the mature larval bag structure. Due to this, young larval bags also bare resemblance to the Australian Hyalarcta huebneri ( Westwood, 1854) and several species of Lomera Walker, 1855 however there are no similarities to mature larval bags, which remain functional in this key.

1. The specimen is an adult male........................................................................... 2

- The specimen is a larval bag............................................................................ 6

2. Thorax covered equally with orange and black scales; anterior orange, posterior black ( Fig. 1 )........................ 5

- Thorax with more black scales than orange, with orange scales confined to the lateral margins of the thorax, around the wing bases and head ( Fig. 2 )................................................................................. 3

3. Dorsal anterior apex of abdomen black with an orange triangular patch of scales ( Fig. 2E ).................. M. oceanica

- Dorsal anterior apex of abdomen black.................................................................... 4

4. Frons yellow ( Fig. 3E ), uncus rounded, saccus very narrow anteriorly, steeply broad towards vinculum, vesica weakly recurved and lightly spined.......................................................................... M. aristocosma

- Frons yellow mixed with brown ( Fig. 3G ), uncus triangular, saccus becoming gradually broader towards vinculum, vesica greatly recurved and heavily spined...................................................... M. phyllosacca sp. n.

5. Frons brown, uncus dorsally rounded ( Fig. 4A ), vesica mushroom-shaped with dorsal aspect less than twice length of ventral, hindwing termen mostly straight, specimen is from mainland Australia.................................. M. elongatus

- Frons yellow, uncus triangular ( Fig. 4C ), vesica with dorsal aspect greater than twice length of ventral, hindwing termen concave, specimen is from Lord Howe Island................................................... M. falcata sp. n.

6. Larval bag adorned primarily with sections of twigs, arranged in loose rows, separated by patches of bare, densely woven silk ................................................................................................... 7

- Larval bag without large patches of bare silk, twigs minimal or absent entirely in design............................. 8

7. Larval bag large, heavily adorned with portions of sticks and foliage at posterior aperture ( Fig. 6B )........... M. elongatus

- Larval bag moderate, posterior aperture bare of foliage or stick adornment ( Fig. 6D ), bag is from Lord Howe Island............................................................................................... M. falcata sp. n.

8. Adorned almost entirely with whole or parts of leaves........................................................ 9

- brush-like bag comprised of fragments of stems and excised leaf veins, approx. 200 mm in length ( Fig. 6A , 7H )................................................................................................... M. aristocosma

9. Bag large, posterior aperture adorned with leaf fragments ( Fig. 6C ), collected in Australia............ M. phyllosacca sp. n.

- Smaller, posterior without leaf fragments ( Fig. 6E , 7B, 7E ), collected in New Caledonia or Vanuatu............ M oceanica

Figures

FIGURE 1. Adult male Metura spp., dorsal and ventral. A–B, M. elongatus (Sydney, NSW, AU), C–D, M. falcata sp. n. holotype (Lorde Howe Isl, AU). Scale bars: 10 mm.

FIGURE 2. Adult male Metura spp., dorsal, ventral. A–B, M. aristocosma holotype (Kuranda, Qld, AU), C–D, M. phyllosacca sp. n. holotype (Caparra, NSW, AU), E, M. oceanica paratype (Malekula, VU), F, M. oceanica holotype (Noumea, NC) ventral. Figure E courtesy of T. Sobczyk (NHM), F courtesy of J. Minet (MNHN). Scale bars: 10 mm.

FIGURE 3. Adult male Metura spp., details of head and thorax of specimens from Figure 1–2. A–B, M. elongatus, C–D, M. falcata sp. n. holotype, E–F, M. aristocosma holotype, G–H, M. phyllosacca sp. n. holotype. Arrowheads indicate areas of diagnostic significance in frons (A, C, E, G) and patagium colour (F). Scale bars 2 mm.

FIGURE 4. Male genitalia of Metura: A–B, M. elongatus dissection ID EPB-017, C–D, M. falcata sp. n. dissection ID EPB- 020, E–F M. oceanica from Viette (1963) with modification, G–H, M. aristocosma dissection ID EPB-021, I–J M. phyllosacca sp. n.; I, dissection ID EPB-022, J, dissection ID EPB-024. K–N: sternite eight, K, M. elongatus dissection ID EPB-017, L, M. oceanica from Viette (1963) with modification, M, M. aristocosma dissection ID EPB-021, N, M. phyllosacca sp. n. dissection ID EPB-024. Abbreviations: aa—anterior apophysis. de—ductus ejaculatorius. sa—saccus. sc—sacculus. tg—tegumen. trtransitellar arm. un—uncus. va—valvae. ve—vesica. vi—vinculum. Scale bars: 1 mm.

FIGURE 6. Larval bags of male Metura spp., A, M. aristocosma, B, M. elongatus (Narara, NSW, AU), C, M. phyllosacca sp. n. (Banyabba, NSW, AU), D, M. falcata sp. n. (Neds Beach, Lord Howe Isl, AU), E, M. oceanica (Duck Isl, NC). Abbreviations: aa—anterior aperture. fa—foliage adornment. pa—posterior aperture. Scale bar: 20 mm.

FIGURE 7. Larvae of Metura spp., A, M. elongatus (Warrumbungles, NSW, AU) approximately fifth instar with intermediate bag structure, B, M. oceanica (Pouembout, NC) active early instar larval bag on Ixora margaretae, C, M. aristocosma (Kuranda, Qld,AU) late instar larva, D, M. elongatus (Brisbane, Qld,AU) close-up of head and pronotal shield, E, M. oceanica (Mt Katépaï, Voh, NC) recently eclosed male larval bag with empty pupal exuvia at anterior aperture, F, M. oceanica (near Paagoumène, NC) late instar larva, G, M. elongatus (Vic, AU) late instar larva close-up of head and thorax, H, M. aristocosma (Julatten, Qld, AU) active mature larval bag. Figure B, E courtesy of J. Barrault, C courtesy of A. Mitchell, D courtesy of J. Thynne, F courtesy of E. Bourguet, G courtesy of V. Dunis, H courtesy of D. Herrington.