Hyposmocoma kikokolu Schmitz and Rubinoff

Schmitz, Patrick & Rubinoff, Daniel, 2009, New species of Hyposmocoma (Lepidoptera, Cosmopterigidae) from the remote Northwestern Hawaiian Islands of Laysan, Necker, and Nihoa, Zootaxa 2272, pp. 37-53 : 48-49

Hyposmocoma kikokolu Schmitz and Rubinoff , sp. nov. Figs. 6 , 17, 25

Material examined. Holotype ɗ: [1] ‘H[ AWAI]I: Nihoa , Miller Canyon | “cone” case, VII-17 -[20]07 | em[ergence]. IX-5 -[20]07, #DR07G6 | leg[it]. D[aniel]. Rubinoff, J[esse]. Eiben’; [2] ‘ HOLOTYPE | Hyposmocoma | kikokolu | Schmitz and Rubinoff’. Specimen in perfect condition. Deposited in the UHIM. Paratypes: 6 ɗ, 7 Ψ from Nihoa Island, Hawaii, USA: 2 ɗ, 4 Ψ, with same data as holotype except date of emergence: VIII-22 -[20]07 (1 ɗ, 1 Ψ), VIII-27-07 (1 Ψ), IX-2-07 (1 Ψ dissected, slide PS128), IX-4-07 (1 Ψ), IX-13-07 (1 ɗ, dissected, slide PS130); 3 ɗ, 3 Ψ, with same data as holotype except date of emergence and rearing log number: VIII-28-07, #DR07G9 (1 ɗ, dissected, slide PS141); IX-4-07, #DR07G2 (1 ɗ); IX-7-07, #DR07G9 (1 ɗ); IX-10-07, #DR07G2 (1 ɗ, dissected, slide PS129; 1 Ψ, dissected, slide PS127); X-5-07, #DR07G2 (1 Ψ); X-11-07, #DR07G9 (1 Ψ). Deposited in BPBM, MHNG, UHIM, and USNM.

Diagnosis. Hyposmocoma kikokolu is a mostly uniform grayish-brown species. Based on external characters H. kikokolu can be separated from the closest looking species, H. menehune , by its larger size (wingspan between 8.0 and 10.0 mm vs 7.2 and 7.4 mm), and the thinner sclerotized hook in males. The two species are also allopatric. The genitalia are diagnosed in the treatment of H. menehune .

Description. Male (n=6) ( Figs. 6 , 17). Wingspan 8.0– 10.2 mm (Holotype: 9.5 mm). Head mostly grayish brown with dark-brown scales on each side, and beige to reddish-brown scales around eyes, with few, if any, reddish-brown and off-white scales on base of occiput; larger smooth grayish-brown to whitish-brown scales on vertex, replaced on the frons by smaller off-white scales. Base of haustellum with off-white scales. Maxillary palpus reduced. Labial palpus slender and recurved with off-white scales ventrally and dark brown scales dorsally. Antennal flagellum dark gray with apical off-white ring on first 5–12 flagellomeres; scape dark gray with off-white scales ventrally and forming ring apically, antennal pecten present with row of 5 or 6 thin setae. Thorax mostly dark brown, with some grayish-brown scales on lateral margins; tegulae with a mixture of grayish-brown and dark-brown scales; metascutellum silver gray. Foreleg dark brown with offwhite ring at middle and apex of tibia, and apex of tarsomeres I, II, and V. Midleg as foreleg, spurs off-white. Hindleg as midleg, but more grayish brown and with off-white rings at apex of tarsomeres I–V. Forewing base dark brown otherwise wing mostly covered with grayish-brown-tipped off-white scales; dark brown markings as pair of oblong spots medially, disconnected from each, with most basal spot below other, and more or less conspicuous small spot postmedially on midline; off-white markings as small notch subapically on costa and another opposite on inner margin. Hindwing and fringe uniformly silver-gray. Subcostal brush absent. Abdomen dorsally silver-gray; ventrally off-white, with tuft of long off-white scales on each side of genitalia. Sclerotized hook of segment VII elongate, very slightly curved, large basally and narrowing apically to acute apex arising from thin sclerotized ring. Genital flaps membranous, rounded, large, and thin, arising on both sides at apex of sclerotized sternum VIII.

Male genitalia (n=2) ( Fig. 17). As for H. opuumaloo , except for bulbous anellus lobes at apex.

Female (n=7). Wingspan 9.0–10.0 mm. Frenulum with 3 acanthae. Antennae slightly thinner than that of male. Head, labial palpus, and thorax darker; metascutellum and first abdominal segment dark brown; ground color of forewing more dark gray. Otherwise externally like males.

Female genitalia (n=2) ( Fig. 25 ). Papillae anales short. Anterior apophyses straight with slight angle at base; posterior apophyses thin and straight, about 2.5 X length of anterior apophyses. Ostium bursae heavily sclerotized and very large, externally protruding, snailshell shaped curled to the left, with broad base. Ductus bursae long and of small girth. Corpus bursae oval and elongate, with light scobination; signum absent. Inception of ductus seminalis very enlarged, cylindrical, situated at posterior end of corpus bursae. Apical margin of tergum VIII with broad U-shaped emargination medially forming a bowl encompassing ostium bursae with patches of dense scales situated laterally.

Larval case (n=318). Cone-shaped, 6.0– 8.7 mm in length, small and thin, decorated with beige, brown, and black sand grains; operculum of case covered with small pebbles; background color ranging from gray to grayish brown.

Etymology. From the Hawaiian kiko, spot, and kolu, three, referring to the pattern of the forewing.

Biology. All adults were reared from case-making larvae. Larvae were collected on the ground during the day on the island of Nihoa in July. As noted, most cone-cased Hyposmocoma in the main Hawaiian Islands are aquatic (Rubinoff 2008), but streams do not exist in the NWHI.

Distribution. Known only from the NWHI of Nihoa , where it is presumed to be endemic. Remarks. This species may represent the new species 28 of Zimmerman (1978), collected on Nihoa Island, based on characters such as absence of subcostal brush, presence of sclerotized hook, male genitalia, and thornlike larval case.

Figures

FIGURES 1 – 8. Holotypes of Hyposmocoma spp., adult males. 1. H. laysanensis; 2. H. ekemamao; 3. H. opuumaloo; 4. H. mokumana; 5. H. nihoa; 6. H. kikokolu; 7. H. menehune; 8. H. papahanau.

FIGURES 20 – 26. Female genitalia of Hyposmocoma spp., ventral aspect 20. H. laysanensis (slide PS 124); 21. H. ekemamao (slide PS 139); 22. H. opuumaloo (slide PS 134); 23. H. mokumana (slide PS 126); 24. H. nihoa (slide PS 133); 25. H. kikokolu (slide PS 127); 26. H. menehune (slide PS 136).