Zeaphilon, Leschen & Reid & Nadein, 2020

Leschen, Richard A. B., Reid, Chris A. M. & Nadein, Konstantin S., 2020, Generic Review of New Zealand Chrysomelinae (Coleoptera: Chrysomelidae), Zootaxa 4740 (1), pp. 1-66 : 52-53

Zeaphilon , nov. gen.

( Figs. 11 , 12K,M , 13G)

Type species: Z. mirandum , sp. nov.

Diagnosis. Body length greater than 2.5 mm; elliptical and moderately convex; colour uniform black to dar reddish brown, some specimens with a violet metallic reflection. Antennae clavate or subfiliform. Procoxal cavities externally open. Hindwings present but reduced (brachypterous). Anterior edge of metaventrite curved; metaventral lines parallel and not extending to middle of ventrite. First abdominal ventrite with subcoxal lines parallel to coxal cavity and not extending to middle of ventrite.

Description. Length 2.6–3.8 mm. Body elliptical and moderately convex. Colour uniform black to dark reddish brown, rarely with metallic sheen.

Head not forming a short muzzle with genae extending a short distance beyond level of antennal and maxillary insertions, scarcely visible from above with mouthparts directed anteriorly, wide vertex or frons, nearly flat to feebly convex; postantennal calli present but developed, pale areas present or absent; antennal grooves absent. Eyes relatively well-developed, somewhat protuberant, coarsely facetted and consisting of over 30 ommatidia; inner margin of eye without a small seta. Antennae long and clavate or subfiliform, scape elliptical or barrel-shaped, shorter than A2+3 combined, last five antennomeres forming a weak or a distinct club, reaching beyond the hind margin of the pronotum; eye almost contacting insertion, with distance between insertion and margin of eye about length of two ommatidia, distance between insertions about 3–5 times length of the scape. Clypeus trapezoidal, anterior margin straight; frontoclypeal suture present; postclypeal lines present, medial postclypeal line absent. Labrum somewhat rectangular and distinctly transverse, anterior margin weakly emarginated and sides rounded, surface with 3 setae per side, anterior margin at middle lacking distinct setal fringe, tormae long and thin, about 2 times longer than labral plate. Mandible with terebral edge simple. Maxillary palpus relatively short, palpomere 1 about as long as wide, palpomere 2 transverse and shorter than wide, palpomere 3 about 2 times longer than wide, greater in length than palpomere 2, subacute. Labium with relatively wide ligula, about equal in width to the lengths of palpomeres 1 and 2 combined, apex not divided at apex, palpal insertions separated by at least the width of the basal paplomere, palpi relatively short, palpomere 1 quadrate, palpomeres 2 and 3 slightly longer than wide, palpomere 3 subacute. Mentum rectangular and transverse, width of mentum shorter than the length of labial palpomere 3. Intermaxillary process short and not extending anteriorly far beyond maxillary insertions, delimited behind by a sulcus.

Pronotum transverse and convex, with a bead along anterior and lateral margins; posterior edge as wide as the base of elytra; anterior margin emarginated, anterior angles projecting and rounded; sides distinctly converging anteriad and straight or curved, posterior margin weakly convex; posterior angles acute; disc moderately convex without sublateral groove, trichobothria absent, punctation not uniform with coarse and dense punctures at base and nearer to posterior margin; lateral carinae complete. Prosternum vaulted at middle, without transverse notches in front of coxal cavities; prosternal lines present and convergent anteriorly, extending forward almost reaching anterior edge of sternite; prosternal process broad, short and extending a short distance behind procoxae, expanded slightly behind coxae but not contacting the hypomeral process, posterior margin curved; procoxal cavities externally open. Notopleural suture distinct. Scutellary shield visible and relatively small, semicircular with a rounded apex. Elytra strongly convex, humeral calli absent or weakly demarcated by a shallow impression; midbasal stria present or absent; surface smooth, punctures weakly impressed and weakly striate, epipleura wide and well developed, visible in lateral view, apex without ctenidium. Hindwings present but reduced (brachypterous). Mesoventrite mostly hidden in ventral view, posterior portion between mesocoxae visible as a narrow strip; mesal part of mesoventrite with vertical surface confluent with prepectus. Meso- and metacoxae widely separated. Metaventrite equal in length to abdominal ventrite 1 at midline, mesocoxal process very short and broad with a curved anterior margin, metaventral lines parallel and not extending to middle of ventrite; discrimen absent and transverse metaventral (metakatepisternal) suture present, crossing the midline as a weakly impressed line. Metendosternite lacking stalk and laminae, widely spaced lateral arms with subapical anterior tendons. Legs with tibiae flattened in cross section, meso- and metatibiae not clubbed and gradually expanded before apex and flattened with evenly curved lateral outline, apically setose; tarsomeres 5-5-5 with tarsomere 1 about 2 times longer than T2 (enlarged in male), 1.5–2.0 times longer than wide, T2 slightly wider than long and as wide as T1, T3 slightly longer than wide and incised (bilobed), tarsomere 4 minute, T5 about twice as long as T3, claws appendiculate or weakly so.

Abdominal ventrite 1 long, but shorter than ventrites 2–5 combined, with a broad metacoxal process that is wider than long and with a straight apical margin, ventrites 2–4 equal in length and shorter than or equal to ventrite 1, ventrite 5 longer than ventrites 3 and 4 combined with rounded posterior margin; first abdominal ventrite with subcoxal lines parallel to coxal cavity that do not extend to middle of ventrite. Aedeagus weakly curved in lateral view and dorsoventrally compressed in cross section; apex in dorsal view square-edged and may be notched; flagellum present. Ovipositor with coxite 2 times longer than wide, stylus absent. Spermatheca curved, C-shaped, collum present with spermathecal duct inserted onto base, accessary and spermathecal glands present and sclerotized.

Comments. This endemic genus contains two species, both living at ground level and collected by sifting leaf litter or rotten wood. Recent field collecting focussing on sifting forest-dwelling mosses indicates that these species may be moss specialists. They are easily separated from other endemic genera by having a vaulted prosternum and brachyptery. In some respects species of Zeaphilon are similar to Maurodus , but having the coarse basal pronotal punctures similar to those present in Aphilon and having parallel metaventral lines as in Nanomela which can also seperate the genus from the similar looking Australian genera Canobolas Reid, Jurado-Rivera & Beatson and Geomela Lea.

Etymology. A neuter name that combines the first two letters of “Zealand” with the name “ Aphilon ”.

Included species. Zeaphilon marskeae , sp. nov.; Z. mirandum , sp. nov.

Distribution. North Island, South Island.

Figures

FIGURES 11A–G. Habitus of Zeaphilon spp.; A, Zeaphilon marskeae, dorsal; B, Zeaphilon marskeae, lateral; C, Zeaphilon marskeae, oblique lateral; D, Zeaphilon mirandum, dorsal; E, Zeaphilon mirandum, ventral; F, Zeaphilon mirandum, lateral; F, Zeaphilon mirandum, oblique lateral.

FIGURES 12A–N. Habitus and genitalia; A, Nanomela sp., dorsal, scale = 1 mm; B, Nanomela tiniheke, dorsal, scale = 1 mm; C, Maurodus maculatus, aedeagus, dorsal view; D, Maurodus maculatus, aedeagus, lateral view; E, Maurodus occiduus, aedeagus, dorsal view; F, Maurodus occiduus, aedeagus, lateral view; G, Maurodus nunni, aedeagus, dorsal view; H, Maurodus nunni, aedeagus, lateral view; I, Maurodus supernus, aedeagus, dorsal view; J, Maurodus supernus, aedeagus, lateral view; K, Zeaphilon marskeae, aedeagus, dorsal view; L, Zeaphilon marskeae, aedeagus, lateral view; M, Zeaphilon mirandum, aedeagus, dorsal view; N, Zeaphilon mirandum, aedeagus, lateral view.