Philiris baiteta Mueller

Mueller, Chris J., 2014, Six new species of Philiris Roeber, 1891 (Lepidoptera, Lycaenidae) from Papua New Guinea, ZooKeys 395, pp. 33-55 : 40-42

Philiris baiteta Mueller sp. n. Figs 29-33, 64

Type material.

Holotype ♂ (Figs 29-31): "Papua New Guinea, Hindenburg Range, Western Province, 1000 m, 5°13'S, 141°14'E, 13-17 Feb, 2013, Chris J. Müller, genitalia dissected and held in vial pinned to specimen, (ANIC), Registration: ANIC Database No. 31-023124. Paratypes (8 ♂♂, 1 ♀): 4 ♂♂ labelled the same as the holotype (1 ♂ AM, 1 ♂ BMNH, 2 ♂♂ CJMC); 3 ♂♂ labelled "Papua New Guinea, Baiteta, Madang Prov. 5°00'S, 145°44'E, 380 m, 6 August 1987, D.P.A. Sands (on loan to ANIC); 1 ♂ labelled the same as last but 31 July 1987 (on loan to ANIC); 1 ♀ labelled "nr. Oetakwa R., Snow Mts., Dutch N. G., up to 3500 ft., x. xii. 1910 (Meek)" (BMNH).

Diagnosis.

Philiris baiteta is a distinctive species that was previously confused with the related Philiris hypoxantha (Figs 34, 35). The type specimen of Philiris hypoxantha from south-western Papua Province could not be located but the description (in German) by Röber (1926) is detailed and he describes the wings above as 'monotonously sepia-brown with low shine’ Röber (1926, p. 375, translated).

A single female of Philiris baiteta in the BMNH (Fig. 32, 32) was recognised tentatively as a ‘form’ of Philiris hypoxantha by Tite (1963) who also added comment that its significance could not be assessed until more material became available. This is obviously the true female belonging to Philiris baiteta .

Philiris baiteta is readily distinguished from Philiris hypoxantha by the large area of cream-white in the costal and subapical area of the hindwing upperside. Both wings above are uniformly brown in Philiris hypoxantha . The underside of Philiris baiteta is cream-yellow, with a broad cream border to the greyish area on the inner margin of the forewing. Conversely, in Philiris hypoxantha , the underside is bright yellow.

The unusual male genitalia of Philiris baiteta (Fig. 64), Philiris hypoxantha (Fig. 66) and Philiris hemileuca (Fig. 65) emphasise a close relationship of the three taxa, yet each show vast differences in their morphology, in particular the shape of the valva. In all three species the valva is sharply tapered to a spike anteriorly. In both Philiris hemileuca (Fig. 65b) and Philiris baiteta (Fig. 64b) an additional posterior dorso-lateral spike is present, which is much longer and more pronounced in the latter species than in Philiris hemileuca . The phallus of the three species also exhibit notable differences with Philiris hypoxantha bearing an apically enlarged vesica (Fig. 66c), which is bifurcated in Philiris hemileuca (Fig. 65c), yet rather abruptly terminated in Philiris baiteta (Fig. 64c). Parsons (1998) noted that the male genitalia of Philiris hypoxantha bear some resemblance to those of Philiris vicina (Fig. 77), especially in the shape of the valvae and aedeagus.

Description.

♂ (Figs 29-31): Forewing length 14 mm, antenna 8 mm (holotype). Head, palpus and thorax dark brown dorsally, white ventrally, abdomen dark brown dorsally, white ventrally, frons dark grey with white eye ring; legs white with black areas on tibiae; antenna shaft black, ringed conspicuously with white between segments, club wholly black.

Fore wing termen nearly straight, inner margin straight, apex pointed; upperside with ground colour dark uniform brown, cilia brown; underside pale yellow-cream, grading through white towards inner margin where the area between the inner margin and vein 2 and the cubitus are light grey-brown, cilia dark brown.

Hind wing slightly acute at tornus; upperside with ground colour dark uniform brown, a large cream-white apical area extending from base to beyond vein 6 into space 5 but not connected to termen; cilia dark brown except at apex where they are cream; underside uniformly pale yellow, cilia as in upperside.

Male genitalia (Fig. 64): Vinculum and tegumen ring rather rectangular, sociuncus rather broad, square-shaped, socii with lateral margin square-shaped, dorsally rounded, socii not obviously separated by sinus, saccus tapered posteriorly, brachium tapered dorsally; valvae symmetrical, bulbous dorsally at base but flat, boat-shaped laterally, with long toothed appendage ventro-posteriorly and a shorter appendage dorso-posteriorly; phallus with pre-zonal section approximately equal in length to post-zonal section; zone of compacted cornuti in post-zonal section, vesica apically flanged.

♀: (Figs 32, 33), Forewing length 14.5 mm, antenna 8 mm. Similar to male but larger, wings much more rounded. Forewing upperside with diffuse patch of cream white in median area between veins 2 and 4; forewing underside with brown area along inner margin not reaching termen. Hindwing upperside with cream-white patch slightly more extensive, reaching further into space 5.

Etymology.

This species is named after the locality in Madang Province where Dr Don Sands, Brisbane, Australia, collected part of the type series, also recognising its distinction from the related Philiris hypoxantha .

Distribution.

Western and Madang Provinces, Papua New Guinea; Snow Mountains (Papua), Indonesia.

Ecology.

Both Philiris baiteta (Fig. 87) and Philiris hypoxantha were collected around midday as they settled on foliage some metres above the ground over a rapid flowing stream in precipitous terrain (Fig. 86), together with a number of other Philiris species. Both species exhibited a rapid, fluttering flight.

Remarks.

Philiris baiteta appears to form a small group within Philiris also comprising Philiris hemileuca (holotype; Figs 36, 37) and Philiris hypoxantha (Figs 34, 35) and Philiris baiteta appears to fall midway between the two. All species have been taken in the Hindenburg Range area, Western Province, where Philiris hemileuca occurs above about 1500 m, while Philiris hypoxantha and Philiris baiteta have been taken together at around 1000 m. The latter two species have also been taken flying together elsewhere, in the Snow Mountains, where A. Meek even collected both species on the same day.