Atyphella marigenous, Saxton & Bybee, 2020

Saxton, Natalie A., Powell, Gareth S., Martin, Gavin J. & Bybee, Seth M., 2020, Two new species of coastal Atyphella Olliff (Lampyridae: Luciolinae), Zootaxa 4722 (3), pp. 270-276 : 273-275

Atyphella marigenous, Saxton & Bybee , sp. nov.

( Figs. 1C, F, I ; 2C )

Type material. Holotype male ( Fig. 1D ): // Vanuatu: Efate Is. / 1999 Devil’s Point Rd. , -17.6841 / 168.2536, 12.vi.2018 / coll. S. Bybee & G. Powell // ( BYU) . Paratypes (7 males): (2 ANIC, 2 BYU, 1 USNM) Vanuatu: Efate Is. / 1999 Devil’s Point Rd. , -17.6841 / 168.2536, 12.vi.2018 / coll. S. Bybee & G. Powell // (2 NHM) Vanuatu: Efate Is. / Epule , -17.5714 / 168.4702, 13.vi.2018 / coll. S. Bybee & G. Powell //

Diagnosis. Atyphella marigenous is distinguished from all other South Pacific Atyphella , except A. aphrogeneia and A. maritimus by the thickened elytral apices in conjunction with a dark median marking on the pronotum (see Ballantyne and Lambkin 2009). Atyphella marigenous resembles A. maritimus and A. aphrogeneia but differs in the following ways: frons is deeply excavated (shallower in A. maritimus and A. aphrogeneia ); pronotum broadly and continuously rounded (pronotum with weakly obtuse and anterior angles in A. aphrogeneia ); base of scutellum with less dense and larger punctation (apex of scutellum with dense punctation at the base in A. maritimus ); elytral costae pronounced (elytral costae less pronounced in A. aphrogeneia and A. maritimus ).

Description. Holotype. Male. Overall, body parallel-sided, length 10mm, width measured at elytral humeri 3.4mm. Coloration: Elytra and head dark brown to black, pronotum notably lighter, light brown with disc darker ( Fig. 1C, I ). Venter lighter than pronotal margins, becoming darker apically but before the light organ. Sculpturing on dorsal body surfaces moderately shiny beneath pubescence; pubescence fine and gold in color. Legs at base tan, becoming darker distally. Head: 2.3mm at widest point (center of eyes), eyes large, black; frons deeply depressed, depression narrow and deep, gradually widening and becoming shallow towards clypeus, small, red apunctate region at narrowest point of depression, setae long and golden on frons; antennae filiform, light brown at scape and second antennomere and becoming darker distally; scape about 0.3mm long, antennomeres 2–11 broadly uniform in length and about half as long as scape; mandibles broad, reddish brown, darker toward pointed apices; apical maxillary palpomere enlarged, widest almost at base, apex rounded, longer than wide; apical labial palpomere longer than wide, similar to that of apical maxillary palpomere but smaller and thinner, half as long as apical maxillary palpomere. Pronotum: 2.2mm long, 3.6mm wide, pronotal width slightly less than humeral width; margins light brown, basal third subparallel, broadly rounded anteriorly, weakly explanate, hind angles almost at right angles; disc dark brown, dorsal surface with dense punctation, with dark median region not reaching either anterior or posterior margins, median area of dorsal surface somewhat convex. Scutellum: trapezoidal with dense punctation, distance between punctures increasing anteriorly; brown with lighter lateral and posterior margins. Elytra: 7.9mm long, dark brown almost black, parallel–sided; punctures dense, not as large as that on pronotum, unevenly spaced; costae epipleuron developed as ridge along margin, widest at humeri, narrowing posteriorly, weakly developed towards apex; Costae well pronounced, becoming less distinct apically. Abdomen: Ventrites 1–4 tan, becoming darker anteriorly, fat body visible at margins of ventrite 2 to ventrite 4; light organ occupying all of ventrite 5–6. Legs: Dark brown except for pale coxae, trochanters, and basal half of femora; dark marking present on coxae 3. Aedeagus: 1.4mm long, 0.6mm wide, slender, ( Fig. 2C ); median lobe slightly longer than lateral lobes; posterior end of lateral lobes run parallel; lateral margins of lateral lobes symmetrical, tapering to apex, and rounded, diverging anteriorly; interior margins of lateral lobes sclerotized from midpoint to apex; median lobe apex rounded and deeply ventrally excavated.

Variation. Males: Length 9.6–10.2mm (n=6), width 3.1–3.4mm (n=6). Pronotum of some specimens lighter in color, some with wider disc. Antennae color in some specimens generally uniform. Female: unknown.

Etymology. In reference to this species habitat, the specific epithet for this species is derived from the Latin roots mar- referring to “the sea” and -genous meaning “the product of.”

Biology. Atyphella marigenous was collected on volcanic rock outcroppings extremely similar to those A. maritimus inhabit. Larvae were found in crevices on the rocks despite the frequent waves from the ocean. Larvae of all sizes were collected suggesting that this species reproduces year-round. Adult males were caught flying over these rocks, but no females were observed. The similar biology and morphology of this species to both A. maritimus and A. aphrogeneia suggest these species are closely related.

Figures

FIGURE 1. A–I) Atyphella spp. holotypes. A–C) dorsal pronotum: A) A. aphrogeneia, B) A. maritimus, C) A. marigenous; D–F) scutellum: D) A. aphrogeneia, E) A. maritimus, F) A. marigenous; G–I) left elytron, notice extent of costae G) A. aphrogeneia, H) A. maritimus, I) A. marigenous. Atyphella aphrogeneia holotype images are the property of © CSIRO.

FIGURE 2. A–C) Atyphella spp. dorsal view of aedeagus. A) A. aphrogeneia holotype, B) A. maritimus paratype, C) A. marigenous holotype. Atyphella aphrogeneia holotype images are the property of © CSIRO.