Hyposmocoma nihoa 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 : 46-47

Hyposmocoma nihoa Schmitz and Rubinoff , sp. nov. Figs. 5 , 11 , 16 , 24

Material examined. Holotype ɗ: [1] ‘H[ AWAI]I: Nihoa , Miller Canyon | “burrito” case, VII-17 -[20]07 | em[ergence]. VIII-16 -[20]07, #DR07G8 | leg[it]. D[aniel]. Rubinoff, J[esse]. Eiben’; [2] ‘ HOLOTYPE | Hyposmocoma | nihoa | Schmitz and Rubinoff’. Specimen in perfect condition except for broken antennae. Deposited in the UHIM. Paratypes: 3 ɗ, 2 Ψ, from Nihoa Island, Hawaii, USA; 3 ɗ, with same data as holotype except date of emergence: IX-24 -[20]07 (1 ɗ), IX-28-07 (1 ɗ, dissected, slide PS131), X-11-07 (1 ɗ, dissected, slide PS140); 2 Ψ (one dissected, slide PS133), with same data as holotype except date of emergence: VIII-8-07, and rearing log number: #DR07G10. Deposited in BPBM and UHIM.

Diagnosis. Among the known species of Hyposmocoma from the NWHI and within the genus, the black and off-white forewing markings of H. nihoa are unique (see Fig. 5 ).

Description. MALE (n=4) ( Fig. 5 ). Wingspan 6.3–7.2 mm (Holotype: 7.1 mm). Head with large black scales flattened on vertex, replaced on frons by small dark-brown scales. Base of haustellum with black scales. Maxillary palpus reduced. Labial palpus recurved, with off-white scales ventrally and black scales dorsally. Antennal flagellum and scape black, sometimes with off-white scales at base of first flagellomeres; antennal pecten made of three thin setae. Thorax mostly black, with some off-white scales distributed on outer margins, metascutellum dark gray. Foreleg coxa and femur with a mixture of off-white and black scales; tibia and tarsomeres black with off-white 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 with off-white rings at apex of tarsomeres I–V. Forewing mostly black with bluish-green tinge, off-white markings as postbasal triangle with point reaching about 1/4 costa and base between 1/5 and 2/5 on inner margin, and narrower transverse postmedian band of variable width at about 3/4 forewing length. Hindwing gray with grayish-beige fringe. Subcostal brush present on dorsal surface of inner margin as a tuft of long dark-gray scales arising over conspicuous orange spot (not visible on Fig. 5 ) extending 1/3 length of hindwing. Abdomen dorsally uniform shiny dark gray; ventrally off-white, with tuft of long dark gray scales on each side of genitalia. Sclerotized hook of segment VII absent. Genital flaps rounded, elongated and thin; sternum VIII fused dorsally as a band, forming encompassing hull around tegumen.

Male genitalia (n=1) ( Fig. 16 ). Right uncuslike process thick and large, sickle shaped, about 4 X length of left process; left process membranous. Tegumen wide, heavily sclerotized, dorsoventrally flattened. Valvae asymmetrical, with three sclerotized spurlike setae of same length on each valva; right valva spoon shaped, broader, and rounded distally, slightly upcurved and adorned with setae only on apical margin; left valva narrower, more strongly upturned from middle, with low rounded bump on dorsal margin subbasally. Phallus slightly bent to right, stout, blunt tipped, heavily sclerotized, open ventrally, and slightly angled downwards; vesica without spines or cornuti. Anellus with two thin symmetrical lobes adorned with small setae, with very long setae at apex.

Female (n=2). Wingspan 7.6 mm. Frenulum with 3 acanthae. Postmedian off-white band less conspicuous than for male. Otherwise externally like males.

Female genitalia (n=1) ( Fig. 24 ). Papillae anales short, lightly sclerotized and setose, slightly longer than wide. Anterior and posterior apophyses thin and straight, posterior apophyses about 2.5 X length of anterior apophyses. Ostium bursae relatively small, heavily sclerotized, externally protruding, snailshell shaped curled to left, with base slightly larger. Ductus bursae long and thin. Corpus bursae oval and elongate, with light scobination; signum absent. Inception of ductus seminalis enlarged, cylindrical, situated at posterior end of corpus bursae. Apical margin of tergum VIII without medial emargination.

Larval case (n=23) ( Fig. 11 ). Burrito-shaped (for a definition, see Schmitz & Rubinoff 2008), 3.4–4.8 mm in length, large and rounded with curved pointed distal end, decorated with lichens woven with silk filaments; case background color ranging from green to gray.

Etymology. The name of H. nihoa is derived from that of the type locality, the island of Nihoa .

Biology. Adults were reared from case-making larvae. Larvae were collected during the day in July on small bushes and rocks on the island of Nihoa .

Distribution. Known only from the NWHI of Nihoa where it is presumed to be endemic.

Figures

FIGURE 16. Male genitalia of Hyposmocoma nihoa from specimen on slide PS 140. A. Tegumen, ventral aspect; B. Valvae with phallus, ventral aspect.

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 9 – 11. Case types of Hyposmocoma spp., larvae. 9. Cone case type of H. opuumaloo; 10. Purse case type of H. mokumana; 11. Burrito case type of H. nihoa.

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).