Drosophila kikiko Magnacca

Magnacca, Karl N. & Price, Donald K., 2012, New species of Hawaiian picture wing Drosophila (Diptera: Drosophilidae), with a key to species, Zootaxa 3188, pp. 1-30 : 12-14

Drosophila kikiko Magnacca new species

Fig. 1

Diagnosis. This species is virtually identical to D. aglaia from O‘ahu, differing only in lacking a stripe on the upper anepisternum and having slightly more cilia on the front basitarsus of the male (~40–45, compared to 30–35 for D. aglaia ). The irregular wing pattern somewhat resembles some members of the adiastola species group at first glance, but is quite different when examined closely, with the typical markings of the grimshawi group augmented by an extra spot on M and connecting lines between the spots.

Description. Male. Head. Front pale, tinged with brown; ocellar triangle black. Fronto-orbital setae normal, anterior reclinate very small, about half as long as the proclinate and one-third as long as the posterior reclinate. Face and gena pale yellow except for a small black spot below the eye. Antenna with the second segment brown, third segment white; arista with about 11 dorsal and 4 ventral rays in addition to the apical fork, and numerous rather long median branches. One strong oral vibrissa, other oral setulae small and hairlike. Palp black, fading to pale yellow on the basal 1/4, paddle-shaped, broad and flattened, broadest near middle, rounded apically, lacking strong setae. Labellum and mentum dark brown to black. Thorax. Mesonotum largely yellow with three strongly contrasting black stripes, all tapering posteriorly; median stripe reaching the scutellum, lateral stripes ending near the posterior dorsocentral setae. Scutellum black medially for about 1/3 of its length, otherwise smoky. Pleura largely yellow, with three prominent dark marks—a small spot at the base of the wing; a square mark on the anterior margin of the anepimeron; and posterodorsally on the katepisternum, in the area bounded by the katepisternal setae. Two pairs of strong dorsocentral setae, the anterior about 2/3 as long as the posterior. Legs. All yellow except the mid and hind coxae marked with black and hind femur and tibia tinged with brown apically. Front tibia with regular anterodorsal and posterodorsal rows of 13–14 very long cilia along its entire length, longest at the base; about 18 shorter cilia between them dorsally in 1–2 irregular rows. Front tarsus densely covered with numerous irregularly placed dorsal cilia, about as long as those on the lower tibia but distinctly stronger, becoming shorter apically (largely absent from fifth segment); basitarsus with about 40–45 cilia. Wings. Extensively marked, rather irregular (see Fig. 1 ). Apical segment of M over twice as long as the penultimate segment (dm-cu crossvein nearly vertical), r-m crossvein located beyond the middle of cell dm (measured from the subbasal break), well beyond the end of R1. Costal fringe extending about 3/4 the distance between apex of R2+3 and R4+5. Abdomen. All segments with broad yellow areas dorsolaterally, dark brown medially, broadly laterally, and narrowly along the posterior margin. Cerci about as long as high or slightly longer, smoky yellow-brown. Genitalia not dissected.

Female. Identical to the male with the following exceptions. Head. Front noticeably brown. Third antennal segment tinged with brown. Palp with a moderately strong apical seta. Legs. Front legs without elongate cilia or setae. Abdomen. Ovipositor long, straight, yellow, pointed posteriorly at rest.

Types. Kaua‘i: Holotype 3, Kōke‘e State Park, Nu‘alolo Trail, 3800 ft., 22.132°N 159.660°W, on bait sponge, 23.i.2010, K. Magnacca (UHIM). Allotype Ƥ, Ku‘ia Natural Area Reserve, Mahanaloa–Ku‘ia Valley junction, 1900 ft., 22.137°N 159.701°W, on bait sponge, 23.vi.2009, K. Magnacca (UHIM); paratypes: 1Ƥ, same locality as holotype, 25.vii.2010, D. Kapan (BPBM). 1Ƥ, Kōke‘e, 3600 ft., 22.vi.1964, H.L. Carson, C99.25 (UHIM).

Distribution and ecology. Kaua‘i, in diverse mesic forest. Breeding hosts unknown (see Discussion below).

Etymology. From the Hawaiian kikiko , spotted or mottled, referring to the wing pattern.

Discussion. Like its O‘ahu relative, this species is extremely rare. Two captive females were offered vials with extracts from bark of Charpentiera , Cheirodendron , Clermontia , Pisonia , Tetraplasandra , Touchardia , Urera , and Wikstroemia over the course of three weeks, but did not lay any eggs. The most likely host is Pleomele aurea , because it is the only known potential host plant observed at both of the collection sites; unfortunately, none of this was available as an oviposition stimulus. Notably, Kaua‘i is the only island not yet known to have an oligophagous picture wing species on either Pleomele or Tetraplasandra (Magnacca, et al., 2008; the generalist species D. crucigera and D. villosipedis utilize both), despite both being much more abundant there than on other islands.

The closely-related D. aglaia is a federally listed endangered species ( U.S. Fish and Wildlife Service, 2006).The host recorded in the literature is Urera glabra (Magnacca, et al., 2008; Montgomery, 1975), but this was based on misidentification of D. kinoole (described below). Since D. aglaia has not been seen since 1997 and its host plant is now unknown, a thorough search for the host of D. kikiko may be informative for management of D. aglaia .

Figures

FIGURE 1. Drosophila kikiko. A. Right front leg of male, anterior view. B. Wing. C. Thorax, lateral view. D. Drosophila aglaia thorax, lateral view.