Philodoria sciallactis ( Meyrick, 1928 )

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 : 104-109

Philodoria sciallactis ( Meyrick, 1928)

Figs. 24A–G , 53A, B , 54A , 55A , 60D , 78A–C , 91A–G .

Parectopa sciallactis Meyrick, 1928:104 .

Parectopa lipochaetae Swezey, 1946: 627 . A junior subjective synonym of Parectopa lipochaetaella Swezey, 1940 , synonymized by Zimmerman (1978a: 681).

Philodoria sciallactis ( Meyrick, 1928) ; Zimmerman 1978a: 690, figs. 445, 451, 458; Johns et al. 2016: 369, figs. 1, 2; Johns et al. 2018: fig. 2.

Philodoria sp. 6; Johns et al. 2018: fig. 2.

Type locality. Kaena Point (Oahu).

Type material. Lectotype ♂, Kaena Point, Oahu, 11.xi.1927, O.H. Swezey Collector, Lipochaeta [= Melanthera integrifolia ], | Holotype | Parectopa sciallactis Mey. teste Meyr.| in BPBM. (here designated) Paralectotype 6 (3♂, 3♀). [Same data and locality as lectotype with following label: | Paratype | Parectopa sciallactis Mey. teste Meyr.|]: 2♂, 1♀, ♂| BPBM 34280, SK 713♀ | BPBM 34281, SK711♂| BPBM 34282; 1♂, |B.M. Genitalia slide no. 2754|Meyrick Coll. B.M. 1938-290|BMNH(E) 1407859| NHMUK 010305339| Paratype | in NHMUK; 1♀, | PARECTOPA Clem. | sciallactis Meyr. |BMNH(E)1407866| NHMUK 010305340| Paratype | in NHMUK; 1♀, SK 712♀ in USNM. Described from seven specimens reared from ‘fleshy leaves of Lipochaeta integrifolia [= Melanthera integrifolia ], growing in rocky places near the seashore’ ( Meyrick 1928). Specimen labels suggest that Meyrick considered one of these specimens to be the holotype and the remaining specimens as paratypes. However, because a holotype specimen was not formally designated in the original description, the so-labeled holotype and paratypes can be considered syntypes under Article 73.2 of the Code ( ICZN 1999), and any of them are eligible for designation as the lectotype under Article 74 of the Code ( ICZN 1999). The syntype labeled ‘Holotype’ is here formally designated as lectotype ( Fig. 24B ) and the remaining syntypes are paralectotypes.

Additional material. (5♂, 1♀, 2 sex unknown) 1♂, Mokio, Molokai, 29.xii.2013 (stored), C.A. Johns leg., host: Melanthera rockii [= Lipochaeta rockii ], 16.xii.2013, CJ159, SK759♂ in BPBM; Maui: 1♂, 1♀, 2 (sex unknown), Lahaina, 23.xii.1928, O.H. Swezey Collector, ex Lipochaeta larvarum, BPBM 34184, SK699♂| BPBM 34185, BPBM 34186,| Holotype Parectopa lipochaetae Swezey |Type no. 4259|; 3♂, Lualailua, 30.xii.2013 & 4.i.2014 (stored), C.A. Johns leg., host: Melanthera kamolensis , 24.xii.2013, CJ163 / SK688♂, CJ164 / PHIL0024♂, CJ189 / SK689♂ in BPBM. 1♀, 2 (sex unknown), Kaena Point, Oahu, 6–11.vii.2014 (stored in RNAlater solution), C.A. Johns leg., host: Melanthera integrifolia , 1.vii.2014, AHE_56, CJ271 / PHIL0034 ♀, CJ273 (no abdomen), CJ274 (no abdomen), ‘ Philodoria sp. 6 of Johns et al. (2018) ’, in FLMNH.

Diagnosis. The forewing pattern is similar to that of P. marginestrigata (Walsingham) , but this specimen can be distinguished by its large white patches on the forewing ( Fig. 24A–G ). See also diagnosis of P. lipochaetaella .

Redescription: Adult ( Fig. 24A–F ). Wingspan 4.5–6 mm in paralectotype; forewing length 1.8–2.5 mm in paralectotype. Head and frons whitie; maxillary palpus white; labial palpus white, sometimes with fuscous rings at apex of second segment and in middle of terminal segment. Antenna white ringed fuscous. Thorax white to graywhite. Forewing white, sometimes partially suffused light gray with light ocherous to yellow patches, margined with fuscous scales: a median streak (mp) from base to 1/3, meeting apex of an oblique narrow line from base to 1/8 of near dorsum; a small spot at dorsal 1/7 (dp 1); three oblique costal patches (cp 1–3): cp 1 about 1/2, cp 2 at 3/4, reaching half across wing; cp 3 short, before apex; an oblique dp 2 at 1/2, meeting cp 1 and cp 2; apical portion white with light ocherous scales at middle, containing a black as; cilia white or white gray, with bl 1 and bl 2 from termen to tornus. Hindwing gray; cilia white. Abdomen ocherous. Legs white, tarsi with fuscous scales.

Male genitalia ( Figs. 53A, B , 54A , 55A ) (n=6). Capsule 590 µm. Tegumen 0.9 x length of valva; valva 420 µm long, tapering along costal margin from 1/2 to apex; apical half digitiform, slender and slightly curved toward inner margin with small spines at apex; a set of short spines arranged along inner side of basal region ( Fig. 53A, B ). Saccus short and triangular in ventral view ( Fig. 54A ). Phallus 400 µm long and slightly widening at phallobase with developed coecum; cornuti in vesica indistinct ( Fig. 55A ).

Female genitalia ( Fig. 60D ) (n=2). 1060 µm long. Ostium bursae large; antrum large, cup-shaped with a pair of lateral lobes; lamella antevaginalis 140 µm, weakly sclerotized, inflexed on the posterior margin, widening toward anterior margin of A7. Ductus bursae rather short, middle region weakly sclerotized, round and flat; terminus of the ductus bursae tubular, biforked. Corpus bursae 640 µm, pyriform; anterior end of corpus bursae weakly sclerotized; signa absent.

Distribution. Oahu ( Meyrick, 1928), Molokai and Maui: new record.

Host plants. Asteraceae : Melanthera integrifolia (Nutt.) W.L.Wagner & H.Rob. ( Meyrick 1928; Johns et al. 2016), M. kamolensis (O.Deg. & Sherff) W.L.Wagner & H.Rob. (Endangered, IUCN) and Lipochaeta rockii Sherff are new record.

Biology. ( Fig. 91A–G ) The larva mines the fresh leaves of Melanthera integrifolia forming a blotch mine which expands to cover the entire leaf as the larva grows ( Fig. 91A, B ). Pupation occurs in the cocoon outside of the mine; cocoon is white ellipsoid ( Fig. 91C ). Mines on M. integrifolia are very difficult to find. Larvae that feed on Lipochaeta rockii form a blotch mine and have a white, ellipsioid pupal cocoon ( Fig. 91D, E ). On a leaf of M. kamolensis , we observed a similar cocoon to that of L. rockii . Cocoons were often found on the adaxial leaf surface, centered on the midvein.

Remarks. We surveyed some Melanthera populations in the lowlands of Maui but did not find any Philodoria mines. The East Maui specimens feeding on Melanthera kamolensis have generally darker brown patches ( Fig. 24E–G ), similar to specimens from the type series of P. lipochaetaella , but these specimens are P. sciallactis based on male genitalia. The East Maui specimens are from the same series as P. sciallactis of Johns et al. (2018: fig. 2, AHE_4/CJ-145). Pholodoria sp. 6 of Johns et al. (2018) is here treated as P. sciallactis based on female genitalia: three specimens of P. sp. 6 (CJ271, 273 & 274) were collected from the type locality of P. sciallactis and female genitalia of CJ271 is poor condition, but similar to that of paralectotype of P. sciallactis . Two specimens (CJ273 & 274) were entirely sacrificed for molecular analysis ( Johns et al. 2018), and no voucher remains. Among specimens from the populations on Oahu, Molokai and Maui, there is phenotypic wing pattern variation and a detailed DNA barcoding study in the future may prove beneficial to futher determine the species boundaries of P. sciallactis and P. lipochaetaella .

Figures

FIGURE 24. Adults of Philodoria species. A P. lipochaetaella, specimens originally described as Parectopa lipochaetae Swezey, 1946, syntype male B P. sciallactis (Meyrick, 1928) lectotype male C Paralectotype male D Paralectotype female E Male left forewing of specimen CJ164, host: Melanthera kamolensis, Maui F Same specimen, right forewing G Male right forewing of specimen CJ189, host: Melanthera kamolensis, Maui H Philodoria sp. B nr. P. sciallactis (specimen CJ483, sex unknown) right forewing, host: Lipochaeta acris, Kauai. Scale bar 1 mm.

FIGURE 53. Valva of Philodoria. A, C, D: Left valva, B: Right valva. A P. sciallactis (syntype of Parectopa lipochaetae), Maui, SK699, B P. sciallactis, paralectotype, C P. ureraella, paralectotype, Oahu, SK676, D P. opuhe, paratype, Oahu, SK674.

FIGURE 54. Genital capsule of Philodoria, excluding right portion of male genitalia, ventral view. A P. sciallactis (syntype of Parectopa lipochaetae), Maui, SK699, B P. ureraella, paralectotype, Oahu, SK676, C P. opuhe, paratype, Oahu, SK682, D Same as C, paratype, Oahu, SK674.

FIGURE 55. Phallus of Philodoria, lateral view. A P. sciallactis (syntype of Parectopa lipochaetae), Maui, SK699, B P. ureraella, paralectotype, Oahu, SK676, C P. opuhe, paratype, Oahu, SK674.

FIGURE 60. Female genitalia of Philodoria. A P. marginestrigata, SK665, B Same species, SK772, host: Abutilon menziesi, C Same species, SK787, host: Sida fallax, D P. sciallactis, paralectotype, SK713, E P. ureraella, paralectotype, SK677, F P. opuhe, paratype, SK675.

FIGURE 78. Resting posture of adult Philodoria on their larval host A P. sciallactis, Maui, CJ195, host: Melanthera kamolensis, B, C P. sciallactis, Maui, CJ164, 189, host: M. kamolensis, D P. ureraella, Maui, CJ316, host: Urera glabra, E, F P. urerana, Oahu, CJ307, host: U. glabra.

FIGURE 91. Philodoria species on leaves of Asteraceae host plants. A–G: P. sciallactis, H, I: P. keahii. Host plants: A–C Melanthera integrifolia, West Oahu, D–F Lipochaeta rockii, East Maui, G Melanthera kamolensis, East Maui, H, I Remya mauiensis, Maui.