Agrotis helela Medeiros, 2019

Kirkpatrick, Jessica, Prestes, Andersonn, Eiben, Jesse & Rubinoff, Daniel, 2019, Two new day-flying species of Agrotis Ochsenheimer (Lepidoptera: Noctuidae) from the alpine summit of the Maunakea Volcano, Zootaxa 4545 (2), pp. 277-285 : 278-281

Agrotis helela Medeiros , sp. nov.

Diagnosis. Agrotis helela is superficially most similar to A. microreas Meyrick. The two are conspicuously smaller than all other congeners, with average forewing lengths of approximately 20–25mm. The two species can be distinguished by the configuration of the white forewing bands: horizontal in A. microreas (see Walsingham, 1907b as well as Fig. 1F ) and vertical in A. helela ( Figs. 1A & 1E ). The male and female genitalia of the two are indistinguishable.

Description ( Figs 1A, 1E , & 2A ). Head: Vertex and frontoclypeus greyish-brown, heavily scaled. Ocelli present. Antenna ca. 0.6–0.7x forewing length; flagellomere bipectinate in males, each segment cylindrical and without triangular processes (sensu Zimmerman 1958 pg 216); flagellomere filiform in female. Labial palpus greyish-brown; porrect; third segment drooping; heavily scaled, length ca. 2.5x diameter of eye; proboscis naked.

Thorax: Grey dorsally and ventrally. Legs grey with lighter scales near apex of tarsal segments; all tibiae and tarsal segments heavily spined; midleg with one pair of tibial spurs; hindlegs with two pairs. Forewing expanse 21– 24 mm (n = 8), dorsal ground color dark grey to black with a few lighter scales near base; prominent whitish antemedial and postmedial bands running from costa to anal margin; faint, poorly defined broad medial band running from costa to anal margin, whitish subterminal spots present; fringe grey; grey ventrally. Hindwing greyish-brown, fringe greyish-brown; light grey ventrally.

Male genitalia ( Fig 3C ): Uncus thin, curved basally then straight, with fine setae along nearly entire length except at base. Tegumen truncated at apex. Valva subrectangular, long, narrow, with band of strong setae immediately basad of corona. Sacculus well defined, extending ~0.7x length of valva and terminating in a pointed apex; ampulla not swollen. Saccus narrow, U-shaped, with anterior spine-like projection. Juxta subrectangular. Aedeagus broad, cylindrical, with long internal sac (sensu Zimmerman 1958 pg 216), apex adorned with very short cornuti.

Female genitalia ( Fig 3D ): Posterior apophysis 1.3x as long as anterior apophysis; ductus bursae 5x as long as anterior apophysis; corpus bursae 2.5x as long as anterior apophysis, signum absent; appendix bursae 9x as long as corpus bursae, apex globose; ductus seminalis originating laterally near corpus bursae apex.

Abdomen: dark grey with tufts of scales projecting laterally from each segment.

Larva: Unknown.

Pupa: Unknown.

Holotype: UNITED STATES: HAWAI‘ I: Hawai ‘ i Island: Mauna Kea, Hale Pohaku Region , 9623 ft, N19°45.835’ W155°27.032’: 1 ♂, 4 Jun 2014, J. Eiben ( UHIM).

Paratypes: UNITED STATES: HAWAI‘ I: Hawai ‘ i Island: Mauna Loa ; 3360m, 15 Jun – 1 Jul 1967: 2 ♂, 10 ♀, R.T. Hansen ( BPBM) . Mauna Loa ; 3360m, 12 Jul 1967: 2 ♀, R.T. Hansen ( BPBM) . Mauna Loa Station , 11,200’, 1–3 Jul 1967: 1 ♂, 1♀, R.T. Hansen ( BPBM) . Mauna Kea , 3900m, 13 Jul 1967: 1 ♀, R.T. Hansen ( BPBM) . Mauna Kea , 4140m, 18 Jun 1967: 1 ♀, R.T. Hansen ( BPBM) . Mauna Kea , 4140m, 18 Apr – 2 Jun 1967: 3 ♀, R.T. Hansen ( BPBM) . Mauna Kea Summit area , 10 May 2005: 1 ♂, 1 ♀, A. Prestes, (vouchers AP116 & AP117; UHIM) . Maunakea, lower Halepōhaku parking lot, 9,260 ft 19.7609 -155.4561: 1 ♀, 1 Jul 2013, J. Eiben ( UHIM) . Maunakea, Halepōhaku region , 10,538’, N19°6.312’ W155°6.909’, 23 Jul 2014: 1 ♂ (slide LB80), 1 ♀, J. Eiben ( UHIM) . Maunakea, summit region, ~13,000’, 19.8194 -155.4745 batch plant parking lot, 6 Aug 2012: 1 ♀ (slides LB81 and LB81 “wings), J. Eiben ( UHIM). Maunakea, west of Halepōhaku , 5 May 2016: 1 ♀, J. Eiben ( UHIM). Mauna Loa, 10,800’, 19.6239 -155.5852: 1 ♂, 29 May 2005, M.J. Medeiros ( UHIM). Maunakea, puʻu south of the Very Long Baseline Array ( VLBA) radio observatory, ~12,140ʻ, 19.7978 -155.4575, 8 Jul 2014: 1 ♂, J. Eiben ( UHIM). Maunakea, batch plant parking lot, ~13,000ʻ 12 Jun 2014: 1 ♀, J. Yoshina ( UHIM).

Etymology. The Hawaiian term “hele lā” means to travel by day, as opposed to “hele pō,” to travel by night. A beloved Hawaiian goddesses of Oʻahu Island is Kaiona, patroness of travelers; her home is on the summit of Kaʻala, and she is referred to as ka wahine hele lā (the woman who travels by day). Agrotis helela , therefore, refers to the Agrotis moth that flies diurnally, though only on Hawai‘i Island.

Remarks. A. helela is diurnal and occurs on both Maunakea and Maunaloa volcanoes. On Maunakea, A. helela are commonly found flying throughout the alpine region on sunny days, even during high winds. Additionally, adults have been observed on flowers of the endemic silversword, Argyroxiphium sanwicense subs. sandwicense that exist in the alpine and subalpine ecosystems on Maunakea. Although we lack information on the larval and pupal stages of this species, we hypothesize that adults occur across the alpine or subalpine region of the volcano, and may facilitate pollination of the Maunakea silversword. Agrotis helela joins the apparently extinct A. microreas Meyrick (http://hbs.bishopmuseum.org/endangered/ext-insects.html) as the second Hawaiian species to be conspicuously smaller than its congeners.

This Agrotis species is not the only diurnal member of the Agrotina subtribe of the Noctuini (Noctuidae) , as several species of Feltia , the sister genus to Agrotis , are diurnal as well. These include Feltia (Trichosilia) woodiana (Lafontaine) and Feltia (Trichosilia) troubridgei Lafontaine , both from northern Yukon territory, Canada, Feltia (Trichosilia) boreana (Lafontaine) , which ranges from Hudson Bay, Canada, to northeastern Alaska, U.S.A., and Feltia (Trichosilia) beringiana (Lafontaine & Kononenko) , from northern Yukon, Canada, to northeastern Alaska, U.S.A., and Chukotka in northeastern Siberia, Russia. Each of these four Feltia species are similar in phenotype to A. helela in being smaller than their congeners. The small body size and diurnal flight behaviors of A. helela and Feltia species are consistent with evolutionary adaptations of arthropods that persist in alpine and high latitude environments ( Somme 1989). Specimens AP116, AP117, and 05A54 had the COI “barcode” region sequenced with primer pairs LCO/HCO (Appendix 1) and have Genbank accession codes listed in Appendix 2.

Figures

FIGURE 1. A: A. helela, paratype voucher AP117, wing expanse 28.5mm. B: A. kuamauna, holotype voucher AP114, wing expanse 46.6mm. C. A. kuamauna, paratype (voucher AP114; UHIM), wing expanse 40.5mm. D: A. epicremna (voucher AP327; UHIM), wing expanse 48mm. E: A. helela, paratype (voucher AP117; UHIM), wing expanse 24mm. F: A. microreas (BPBM), wing expanse 26mm.

FIGURE 2. A: Wing venation of A. helela (from slide LB81 “wings”). B: Wing venation of A. kuamauna (from slide LB82 “wings”). C: A. kuamauna larva, length = 20mm. D: A. kuamauna pupa, length = 15mm.

FIGURE 3. A: A. kuamauna, male genitalia (slide LB83) scale bars = 1mm. B: A. kuamauna, female genitalia (slide LB82) scale bar = 1mm. C: A. helela, male genitalia (slide LB80) scale bars = 1mm. D: A. helela, female genitalia (slide LB81) scale bar = 1mm.