Philodoria hesperomanniella Kobayashi, Johns & Kawahara

Kobayashi, Shigeki, Johns, Chris A. & Kawahara, Akito Y., 2021, Revision of the Hawaiian endemic leaf-mining moth genus Philodoria Walsingham (Lepidoptera: Gracillariidae): its conservation status, host plants and descriptions of thirteen new species, Zootaxa 4944 (1), pp. 1-175 : 83-84

Philodoria hesperomanniella Kobayashi, Johns & Kawahara sp. n.

Figs. 18 , 47J , 48J , 49J , 58L, M , 63A, B , 75B, C , 89 .

Parectopa naenaeiella Swezey, 1940: 462–463 .

Philodoria naenaeiella ( Swezey, 1940) ; Zimmerman 1978a: 685–686, figs. 449, 457, 458.

Philodoria sp. 11; Johns et al. 2018: fig. 2.

Type locality. Waihee Valley (Maui)

Etymology. The specific epithet, hesperomanniella refers to the genus of the moth’s host plant, Hesperomannia .

Type material. Holotype ♂, Waihee Valley , Maui, 12.viii.2014 (stored), C.A. Johns leg., 30.vii.2014, host: Hesperomannia arborescens, CJ 367, SK831♂ in BPBM . Paratype 6 (3♀, 1 sex unknown). 1♀, Pupukea, Oahu, 17.xii.1933, O.H. Swezey Collector, Hesperomannia swezeyi , “ paratype of P. naenaeiella ”, Z-V-17-61, BPBM 34224 ( Fig. 18E ); Host H. swezeyi in BPBM; 2♀, 1 (sex unknown), same locality and data as holotype, C.A. Johns leg., CJ367 / SK 832♀, CJ372 / SK 620♀. The holotype was mounted as a dry pinned specimen ( Fig. 18B, C ) by placing under a coverslip without mountant, two forewings and half of the two hindwings ( Fig. 18A ). The three paratypes were also mounted as partial dry pinned specimens: CJ 367♀ comprises three wings without mountant under a coverslip, two complete forewings and 3/4 of one hindwing ( Fig. 18D ); CJ367 (sex unknown) hindwings missing; CJ 372♀ left hindwing missing .

Additional material. 1♂, 1♀, Iao Valley , Maui, 11.viii.2014 (stored), C.A. Johns leg., 28.vii.2014, CJ362/ PHIL0035♂, 0036 ♀, only genitalia slides, deposited in BPBM. Two specimens have genitalia and abdomen intact .

Diagnosis. Described from a paratype of P. naenaeiella Swezey feeding on Hesperomannia and new specimens collected during fieldwork for the present study. Distinguished from P. naenaeiella by having an outwardly oblique white ds 1 at near base and blue patch at apical potion in the forewing ( Figs.18 , 75B, C ); the male genitalia have a valva widening from the base to the middle and a short and triangular saccus. Swezey (1940) described some paratypes of P. naenaeiella reared from leaves of Hesperomannia swezeyi collected along Pupukea-Kahuku Trail, April 5, 1925, and February 15, 1928. We could not find these specimens among the material in the BPBM.

Description: Adult ( Figs.18 , 75B, C ). Wingspan 7–8 mm in paratype; forewing length 4.1–4.2 mm in holotype, 3.2–4.1 mm in paratype. Head pale ocherous, with some ocherous scales posteriorly; frons white; maxillary palpus white at basal part, mixed with dark brown scales at apex; labial palpus white, second segment broadly infuscated apically, third segment with slight infuscation near base and near apex. Antenna pale brown, basal segment paler and white beneath, about 1.3x length of forewing. Thorax pale brown. Forewing dark brown, with three outwardly oblique white dorsal streaks, all wide at dorsum and narrowing to a point about midway across the wing: ds 1 at near base, ds 2 about at dorsal 2/5, ds 3 at dorsal 2/3; a slender outwardly oblique white cs 3 from 3/5 terminating a little distad from apex of third dorsal streak, an interrupted blue patch from there to apex; all of the white streaks margined with a few black scales; three white costal spots (a, b, c) between cs 3 and apex, separated by fuscous scales; cilia fuscous with distinct darker fuscous bl 1, with white spots at the costal white spots, dorsal cilia pale gray, very long. Hindwing and cilia uniformly grayish fuscous. Abdomen grayish brown. Legs grayish brown, tarsi white banded.

Male genitalia ( Figs. 47J , 48J , 49J ) (n=2). Capsule 940 µm. Tegumen 0.9 x length of valva; valva 660 µm long, widened at basal half and tapering along costal margin from 2/5 to apex, becoming very narrow and slightly curved toward ventral side ( Fig. 47J ). Saccus short and triangular in ventral view ( Fig. 48J ). Phallus about 700 µm long and straight with developed coecum; cornuti in vesica indistinct ( Fig. 49J ).

Female genitalia ( Figs. 58L, M , 63A ) (n=4). Similar to P. naenaeiella . 1230 µm long. Ostium bursae large; antrum cup-shaped with a pair of lateral lobes; lamella antevaginalis 180 µm, weakly sclerotized, indented near the posterior margin, widening toward anterior margin of A7. Ductus bursae short, and middle region weakly sclerotized, round and flat; terminus of ductus bursae tubular, biforked. Corpus bursae 720 µm, nearly pyriform, signa a pair of longitudinal, partly sclerotized wrinkles.

Distribution. Oahu and Maui.

Host plants. Asteraceae : Hesperomannia arborescens A.Gray and H. swezeyi O.Deg. H. arborescens and H. swezeyi are two of Hawaii’s most critically endangered plants ( Morden & Harbin 2013).

Biology. ( Fig. 89 ). Larvae at first form sinuous-linear mine along the leaf margin on the adaxial leaf surface ( Fig. 89A ), which expands as larvae grow ( Fig. 89C, E ). One or two mines per leaf. The late instar larva is pale yellow. The final instar larva folds the leaf tissue lined with silk threads and creates a cocoon on the adaxial leaf surface. The cocoon fold is white ( Fig. 89F ).

Remarks. We collected leaf mines from populations of H. arborescens in the Iao and Waihee valley (West Maui). We were unable to visit the Honokohau valley population of H. arborescens . We also visited the Molokai population of H. arborescens below Olokui summit at the Waiehu Sea Cliffs in July of 2015. No leaf mine activity was observed then. Herbarium specimens from the now extirpated population of H. arborescens on Lana’i ( Morden & Harbin 2013) revealed leaf-miner damage from an undescribed, extinct Philodoria species ( Johns et al. 2014). We visited two populations of H. swezeyi in June/July of 2015. Neither population exhibited any signs of leaf mine damage. However, one collaborator (N. Tangalin) said she had seen leaf mines on these populations in previous years. Herbarium specimens of this plant species also show leaf miner activity. We have not surveyed H. oahuensis (Hillebr.) O.Deg for leaf mine damage. This should be a priority of future surveys of Philodoria , since H. oahuensis is a highly endangered plant ( Morden & Harbin 2013).

Figures

FIGURE 18. Adults of Philodoria hesperomanniella sp. n. A Wings of holotype male, B Same, head and thorax, dorsal view, C Same, head lateral view, D Paratype female, Maui, collected by O. H. Swezey, E Paratype female, Oahu (BPBM no.34224). Scale bar 1 mm.

FIGURE 47. Left valva of Philodoria, inner view. A P. wilkesiella, Maui, PHIL0007, B P. epibathra, Molokai, SK678, C P. dubauticola, Maui, SK646, D P. dubautiella, paralectotype, Oahu SK726, E P. alakaiensis, paratype, Kauai, SK660, F P. limahuliensis, holotype, Kauai, SK731, G P. hibiscella, Oahu, SK684, H P. naenaeiella, paralectotype, Oahu, SK691, I P. knudseniiella, holotype Kauai, SK862, J P. hesperomanniella, holotype, Maui, SK831.

FIGURE 48. Genital capsule of Philodoria, excluding right portion of male genitalia, ventral view. A P. wilkesiella, Maui, PHIL0007, B P. epibathra, Molokai, SK678, C P. dubauticola, Maui SK646, D P. dubautiella, paralectotype, Oahu, SK733, E P. alakaiensis, paratype, Kauai, SK660, F P. limahuliensis, holotype, Kauai, SK731, G P. hibiscella Oahu SK684, H P. naenaeiella paralectotype, Oahu, SK691, I P. knudseniiella, holotype, Kauai, SK862, J P. hesperomanniella, holotype, Maui, SK831.

FIGURE 49. Phallus of Philodoria, lateral view. A P. wilkesiella, Maui, PHIL0007, B P. epibathra, Molokai, SK678, C P. dubauticola, Maui, SK812, D P. dubautiella, paralectotype, Oahu, SK733 E P. alakaiensis, paratype, Kauai, SK660, F P. limahuliensis, holotype, Kauai, SK731, G P. hibiscella, Oahu, SK684, H P. naenaeiella, paralectotype, Oahu, SK691, I P. knudseniiella, holotype, Kauai, SK862, J P. hesperomanniella, holotype, Maui, SK831.

FIGURE 58. Female genitalia of Philodoria. A P. wilkesiella, SK761, B P. epibathra, SK679, C P. dubauticola, SK645, D Same species, PHIL0008, E P. dubautiella, SK692, F P. alakaiensis, paratype, SK659, G Same species, lateral view, H P. hibiscella, SK723, I P. naenaeiella, SK703, J Same species, SK834, K P. knudseniiella, paratype, SK863, L P. hesperomanniella, paratype, SK832, M Same species, SK620.

FIGURE 63. BPBM paratype, genitalia slides prepared by E. C. Zimmerman. A, B: P. hesperomanniella paratype female, Oahu, Z-V-17-61 C, D: P. obamaorum paratype female, Hawaii (Big Island), Z-V-18-61, E–G: P. obamaorum paratype male, Hawaii (Big Island), Z-1-26-61(3), H: P. haelaauensis, paratype female, Maui, Z-XII-19-62-24. A, C, H Female genitalia, ventral view, B, D, G Abdominal segments, E Male genitalia excluding phallus, ventral view, F Phallus, lateral view.

FIGURE 75. Resting posture of adult Philodoria. A Philodoria sp. nr. P dubauticola, Maui, CJ315, host: Dubautia platyphylla, B P. hesperomanniella, Maui, CJ367, host: Hesperomannia arborescens, C Same moth species and host plant, West Maui, CJ362, D, E P. platyphylliella, Maui, CJ368, host: Dubautia platyphylla, F, G Same moth species and host plant, male, Maui, CJ358.

FIGURE 89. Philodoria hesperomanniella leaf mines on its host plant, Hesperomannia arborescens subsp. opuhe, West Maui. A, C Mines of latar larva, B Old mines and cocoon, D Young mine, E Mine of late instar larva, F Cocoon.Arrows point to mine (D) and cocoon (F).