Chrysorthenches smaragdina, 2020

Sohn, Jae-Cheon, Kobayashi, Shigeki & Yoshiyasu, Yutaka, 2020, Beyond Wallace: a new lineage of Chrysorthenches (Lepidoptera: Yponomeutoidea: Glyphipterigidae) reveals a journey tracking its host-plants, Podocarpus (Pinopsida: Podocarpaceae), Zoological Journal of the Linnean Society 190, pp. 709-736 : 724-728

CHRYSORTHENCHES SMARAGDINA SOHN , SP. NOV.

( FIGS 1D, 2C, F, H)

lsid: urn:lsid:zoobank.org:act:F6F3149C-CEC9-4378-8A65-D43429E2E7F8

Diagnosis: This new species is similar to C. callibrya in the male genitalia, but differs from the latter in having the subrectangular valva (obovate in C. callibrya ) and the subtriangular apex of the saccus (digitate in C. callibrya ).

Description: Adult ( Fig. 1D). Head – Vertex yellowish green, with greenish orange piliform scales on temporal and occipital areas; frons yellowish green. Antenna with scape yellowish green; flagellum pale greyish green, intermixed with dark brown scales basally and distally. Maxillary palpus with first palpomere dark brown; second and third palpomeres dark brown, tinged with pale greenish grey apically. Labial palpus with first palpomere yellowish green on outer surface, pale orange on inner surface, tinged with dark brown dorsally; second palpomere 2× longer than first palpomere, dark brown, mottled with yellowish green on outer surface, pale orange on apex and inner surface; third palpomere 2.2× longer than second palpomere, dark brown on outer surface, pale orange on inner surface.

Thorax – Patagium dark yellowish green, tinged with dark brownish green medially; tegula dark purplish brown; mesonotum dark greenish grey, intermixed with dark brown scales anterolaterally; mesoscutellum dark brown. Foreleg with coxa dark greyish brown; femur dark brown; tibia and tarsomeres dark brown, with pale orange ring distally. Midleg with coxa and femur pale orange, intermixed with dark greyish brown scales; tibia and tarsomeres dark brown dorsally, pale orange ventrally, with pale orange ring distally. Hindleg with coxa and femur pale greyish orange, sparsely intermixed with brownish grey scales; tibia and tarsomeres dark brownish grey, with pale orange ring distally. Forewing length 5.2 mm (sample number = 1), dark brown, tinged with yellowish green narrowly along costal area and broadly along dorsal area; apical area dark greenish brown; costal strigulae dark brown, irregularly intermixed with small white bars; subbasal and median fascia bar-like, yellowish green, bordered with pale greyish green, and then with black; dorsal margin with dark brown strigulae; fringe pale greyish green. Hindwing greyish brown, paler to base; fringe brownish grey.

Male genitalia ( Fig. 2C, F, H) – Uncus slightly concave apically, gradually broadened basally; setose area of tuba analis one-quarter of its length. Valva subrectangular; costa nearly straight in basal two-thirds, slightly curved in distal third; sacculus narrow, one-third as long as ventral margin of valva; membranous disc obliquely round, half as long as valva. Vinculum U-shaped; saccus as long as uncus, slightly narrowed at middle, narrowly round apically. Anellus densely spinose ( Fig. 2H). Phallus ( Fig. 2F) with broad, needle-like cornutus one-sixth the length of the phallus; spinulate, digitate cornutus twosevenths as long as the needle-like cornutus; elongate, spinose cornutal zone.

Type: Holotype – ‘ HOLO- | TYPE’ (round label with red edges), ‘ HOLOTYPE | Chrysorthenches | smaragdina | Sohn’ (red label with black marginal lines), ‘N. THAILAND: 1640–1685 m | Nan, Doi Phu Kha NP, | km 33.8 to 34.4, | 26–30.xii.1991 ’, ‘B. M. ♂ | Genitalia slide | No. 32892’, deposited in NHMUK.

Distribution: Thailand.

Etymology: The epithet is derived from the Greek σμαράγδι, ‘ smarágdi ’, emerald, referring to the broad green patch on the forewing of this new species.

PHYLOGENETICS

Our cladistic analyses of the morphological characteristics of 13 yponomeutoids resulted in a single most parsimonious tree ( Fig. 15A: tree length = 74, Ci = 67, Ri = 68). The resulting tree recovers strong support ( Fig. 16: JK support = 100, Bremer support = 5) for the monophyly of Chrysorthenches against the outgroup, Orthenches chlorocoma . The backbone of the tree is divided into two clades. One clade corresponds to the C. callibrya species-group (including C. callibrya and C. muraseae ) and is recovered as monophyletic ( Fig. 16: JK support = 95, Bremer support = 4). The monophyly of the C. callibrya species-group is defined by one unambiguous character ( Fig. 15A). The other clade is divided into two subclades, but the supports are weak.

BIOGEOGRAPHY

Optimal reconstruction of our DIVA analysis requires two dispersals ( Fig. 15B). The result shows three possible scenarios for the ancestral distribution of Chrysorthenches : all areas covering (1) New Zealand – Tasmania –eastern Australia – East Asia, (2) New Zealand –eastern Australia – East Asia or (3) Tasmania –eastern Australia – East Asia. The Chrysorthenches callibrya species-group branched off from the ancestors and dispersed to East Asia. Subsequently, the C. porphyritis species-group diverged and occupied New Zealand and Tasmania. The Chrysorthenches argentea species-group radiated within New Zealand.