Philodoria hibiscella

Philodoria hibiscella (Swezey, 1913)

Figs. 16A, B, 27C–E, 47G, 48G, 49G, 58H, 77B–D, 93A, B, D, E.

Graclaria hibiscella Swezey, 1913: 279–280 (first mentioned as “ Gracilaria hibiscella Sw. ” in Swezey (1913b: 224) without any description).

Parectopa hibiscella Swezey, 1913; Swezey 1928: 191.

Philodoria hibiscella (Swezey, 1913); Zimmerman 1978a: 680–681, figs. 437, 440, 442, 448, 455.

Type locality. Mt. Tantalus (Oahu).

Type material. Lectotype ♀, Mt. Tantalus, Oahu, x.1911, Coll. O.H.S., “from mines in leaes (=leaves) of native Hibiscus ”, Type no. 211, bottom one of two cotypes on the type mount in BPBM. Paralectotype ♂, top one of two cotypes on same mount of lectotype in BPBM.

Described from three specimens collected from type locality from mines in leaves of Hibiscus. We found the lectotype and a paralectotype on same type mount designated by Zimmerman (1978a) but could not find the second paralectotype (sex unknown) (Fig. 16A, B).

Additional material. 13 (5♂, 3♀ 5 sex unknown): Oahu: 1♂, 2 (sex unknown), Honolulu, 1.iii.1914 em., Coll. O.H.S., ex Hibiscus, 24.ii.1914 (Cocoon), SK684♂ BPBM 34179, BPBM 34180, BPBM 34183; 1♀, Manoa, 26.v.1932, O.H. Swezey Collector, ex leaf of Hibiscus, BPBM 34181; 1♂, Waiahole, 13.viii.1933, O.H. Swezey Collector, Hibiscus, genitalia slide no. Z-1-26-61(2), BPBM 34176; 3♂, 2♀, 3 (sex unknown), Tantalus, Coll. O.H.S., ex native Hibiscus, BPBM 34177, SK 685♀ | BPBM 34178, ♀ | BPBM 34182, J.F.G.C. #3753♂, 3754 ♀ and 1♂, 2 (sex unknown) in USNM. Molokai: 1♀, Waiehu Cliffs, 14.iii.2015 (stored), K. Bustamente leg., host: H. arnottianus subsp. immaculatus, 14.i.2012, 20141201KMB01, CJ399, SK 723♀ in BPBM. Maui: 1♂, 1♀, Iao Valley, 29.iv.2013 (stored), C.A. Johns leg., host: Hibiscus tiliaceus, 14.iv.2013, CJ088 / SK 725♀, CJ089 / SK724♂ in BPBM.

Diagnosis. Ocherous forewing with four outwardly oblique white streaks: slender ds 1–3 and one slender cs 3 (Fig. 16A, B). Among Philodoria species having similar ds 1–3 and cs 3 , i.e. P. naenaeiella (Swezey), P. hesperomanniella sp. n., P. neraudicola (Swezey), P. obamaorum sp. n. and P. urerana (Swezey), P. hibiscella is most similar to P. urerana (feeding on Urera), but is distinguishable by the ocherous forewing; males have a rather broad saccus and slender and sinuous phallobase; females signa as two short rows of minute spines in the central area of the corpus bursae.

Redescription: Adult (Fig. 16A, B). Wingspan 9–10 mm in type series; forewing length 4 mm in paralectotype, 3.8–4.5 mm in the additional material examined. Head pale brownish-ocherous; frons white; maxillary palpus brown with white scales; labial palpus pale ocherous-white, terminal segment somewhat fuscous on outer side. Antenna pale ocherous barred with dark fuscous, 1.3–1.4x length of forewing. Thorax pale brownish-ocherous. Forewing ocherous, outwardly-oblique ds 1–3 , widened and black-margined at dorsum; A slender outwardly-oblique narrowly black-margined cs 3 at costal 3/4; 3 or 4 black costal line on apical cilia; a black wide subterminal streak with a few bluish scales; cilia at apex blacky on termen gray with a black line at base. Hindwing and cilia grayishfuscous. Abdomen gray. Legs pale ocherous, anterior legs fuscous on outer side.

Male genitalia (Figs. 47G, 48G, 49G) (n=3). Capsule 920 µm. Tegumen 0.9–1.0 x length of valva; valva 630 µm long, similar to P. limahuliensis except basal portion of valva humped along dorsal margin (Fig. 47G). Saccus slender and digitiform in ventral view (Fig. 48G). Phallus 580 µm long, slender, straight and sinuous at phallobase with developed coecum; cornuti in vesica indistinct (Fig. 49G).

Female genitalia (Fig. 58H) (n=4). 1410 µm long. Ostium bursae large; antrum wide tubular with a slender pair of lateral lobes; lamella antevaginalis 220 µm, weakly sclerotized, trapezoid in ventral view, slightly inflexed on the posterior margin, widening toward anterior margin of A7. Ductus bursae slender, 400–450 µm; terminus of ductus bursae biforked. Corpus bursae 840 µm, pyriformwith paired rows of wrinkles running longitudinally, some sclerotized; two short linear signa with minute spines.

Distribution. Oahu (Swezey 1913c), Maui, Molokai: new record, Hawaii (Big Island) (Zimmerman 1978a: 680).

Host plants. Malvaceae: Hibiscus arnottianus A. Gray, H. rosasinensis L. (Swezey 1928), Hibiscus sp. (Swezey 1913b: 224, 1913c: 280), H. arnottianus subsp. immaculatus and H. tiliaceus L.: new record, endangered subspecies.

Biology. (Fig. 93A, B, D, E). Swezey (1913c: 280) reported its biology: “The mine usually begins towards base of leaf, proceeding upward irregularly and following the margin for a part of its course, it eventually reaches the apex, then follows down the opposite margin of the leaf rapidly widening until the larya, has finished its growth. It then breaks through the epidermic to form its white oval cocoon on the surface of the leaf. Pupal stage about a week.” Zimmerman (1978a) noted that larvae occasionaly cause severe local damage to ornamental Hibiscus, and extensively mined leaves may drop from the plants and the white, oval cocoon is made on the surface of a leaf. We also observed larvae forming first a slender mine along the leaf margin on the adaxial surface that elongated into a blotch mine (Fig. 93B) and expanded as the larva grew (Fig. 93A, B). The frass is brownish green and is deposited in a spiral line. One mine per leaf. Leaves with old mines remained on the host plant and we did not find any indication that larvae cause mined leaves to fall to the ground as in other Philodoria species. The late instar larva is pale yellow to green (Fig. 93D) and pupation occurs in the white cocoon outside of the mine on the leaf adaxial surface (Fig. 93E).

Parasitoids. Eulophidae: Diglyphus sp., Euderus metallicus (Ashmead, 1901), Neochrysocharis formosus (Westwood, 1833), Pauahiana maculatipennis (Ashmead, 1901), Pnigalio externa (Timberlake, 1927) Sympiesis vagans (Timberlake, 1926) (Zimmerman 1978a).

Remarks. The mature larva and pupa described by Swezey (1913c: 280): “ Mature larva. The full-grown larva is about 9 mm.; pale bluish-green; head with blackish mouth-parts, eyes, and 2 lines bordering the paraclypeus, much retracted into segment 2 which is widened, and has a large black spot ventrally and 2 black spots near the anterior margin dorsally; thoracic legs minute; abdominal prolegs on segments 7–9. Pupa. 5 mm.; pale testaceous-greenish, with a few fuscous markings ventrally; wing-sheaths extend to apex of fifth abdominal segment, free beyond fourth segment, dark fuscous at tip; posterior leg-sheaths extend to apex of abdomen; antenna sheaths extend beyond apex of abdomen, recurved over the back forward to base of fourth abdominal segment.”