Zenascus incensum, Grzymala & Leschen, 2020

Grzymala, Traci L. & Leschen, Richard A. B., 2020, Sexual Dimorphism of New Zealand Puppet Beetles (Aderidae, Coleoptera, Tenebrionoidea): Systematic Revision, Description of Three New Genera, and Phylogeny for Zenascus, gen. n., Zootaxa 4889 (1), pp. 1-59 : 38-39

Zenascus incensum sp. n.

Figs 12E , 14J , 15C , 19E , 20J , 22E , 23J , 24F , 27A

Etymology. The specific epithet is in reference to frankincense, one of the gifts brought by the three kings on the Epiphany, which refers to the Three Kings Islands (Manawatâwhi) where this species appears to be biogeographically restricted. The name is formed from the Latin incensum (incense).

Diagnosis. This species is distinguished from congeners by the biseriate pubescence of the pronotum and elytra, the highly modified antennomeres 7–9 of males, and the slightly impressed basal pronotal fovea. Zenascus incensum is most easily confused with Zenascus luniger , but males are distinguished between these two species based on the presence of a distinct vertexal ridge in Z. incensum and the modified shape of antennomeres 7–9 ( Figs 15B & 15C ). Females are more difficult to separate, but currently Z. incensum has only been collected from Three Kings Island whereas Z. luniger has only been collected from the North Island of New Zealand. This biogeographic separation differentiates females of these two species.

Description. Length 1.58–1.84 mm. Head, scape, pedicel, antennomeres 7–11, and pronotum piceus to rufotestaceous; antennomeres 3–6, mouthparts, and elytra brunneous to golden. Dorsal integument matte, vestiture biseriate, one decumbent, thin, short seta arising anterad of each primary puncture, length about 3× puncture length, with 3–4 additional decumbent, thin, shorter setae between each pair of punctures, length about 2/3× primary seta. Ventral vestiture similarly biseriate. Head, HW 0.47–0.50 mm, HL 0.15–0.18 mm, punctation consisting of a few, deep punctures, unevenly spaced on vertex, lacking from base to posterior edge of eyes, strongly impressed and concave between antennal ridge and vertex, occiput of head in male with distinct transverse ridge. Antennae with distance between antennal insertions small, approximately equal to diameter of two antennal insertions; length reaching past basal ½ of elytra when extended backward; scape broad and flattened, approximately 3× length of pedicel; pedicel subglobular; antennomere 3 shorter than pedicel and shorter than antennomere 4; antennomere 4 approximately 3× length of antennomere 3, longer than antennomere 5; antennomeres 5 and 6 subequal in length and width, slightly broader than antennomere 4; antennomere 7 greatly modified, flattened, broad, and branched just anterad of apex, with apex of outer branch terminating in broad triangle, with apex of inner branch connecting to remaining antennomeres, with apex acute, extending ¼ past antennomere 8; antennomere 8 longer than wide, with strong outwards curvature; antennomere 9 with modified outer apex, projecting anteriorly, apex rounded, with dense pilosity extending behind; antennomere 10 subquadrate, slightly expanded apically; antennomere 11 longer than 10; antennomeres 3–11 covered in moderately dense, suberect pubescence, antennomeres 7–9 with additional pilosity; pedicel and antennomeres 3–11 with apical ring of elongate setae, antennomere 11 with additional medial ring of setae. Pronotum, PW 0.38–0.41 mm, PL 0.38–0.41 mm, subquadrate, width subequal to slightly greater than length, width 1.0–1.1× length; pronotal width 0.53–0.59× elytral width, pronotal width 0.81–0.87× head width; sides slightly rounded, posterior angles rounded; disc with two slightly impressed basal fovea, with slight transverse sulcus just anterad of center; punctaion consisting of deep, small elongate punctures, unevenly spaced, more sparse basally and laterally. Elytra 1.67–1.87× longer than wide and 3.15–3.22× longer than pronotal length, EW 0.69–0.72 mm, EL 1.20–1.32 mm; slightly impressed, oblique subscutellar depression present; punctation consisting of elongate punctures, separated by an average of two punctural lengths. Proleg with tarsomere 1 approximately 2–3× longer than tarsomere 2, without a ventral short, stout spine; tarsomere 3 with ventral adhesive setae. Midleg with tibia gently curved inward from base to apex. Hindleg with numerous deep, elongate punctures along posterior margin of coxa; femur with distinctly thickened setae on posterior face, overlying slight medial excavation along length of femur, apico-ventral impression absent; tibia gradually expanded in width from base to apex, apex inner face triangular and apex densely pubescent; tarsomere 1 elongate, length 10× width; tarsomere 2 expanded ventrally. Abdomen with lateral length of ventrite 2 longer than its medial length; deep punctures confined to abdominal process, basal margin of ventrite 1, basal margin and medially on ventrite 2, and a few scattered on ventrite 3; small shallow micropunctures present on ventrites 4 and 5; ventrite 5 without medial impression. Phallobase broadly rounded anteriorly, laterally delimited from apicale; apicale posteriorly narrowed; accessory lobes present, with four setae, one long and two short located at apex, one long located basal to apex on inner face; penis with anterior struts elongate, extending slightly past phallobase.

Females. Length 1.84 mm, HW 0.48 mm, HL 0.18 mm, PW 0.45 mm, PL 0.41 mm, EW 0.78 mm, EL 1.43 mm. Head very slightly impressed, concave between antennal ridge and vertex. Antennae with scape laterally flattened, slightly longer than wide, pedicel subglobular; antennomere 3 slightly reduced in width compared to pedicel, slightly expanded apically; antennomere 4 slightly longer than 3; antennomeres 4–6 subequal in length and width; antennomeres 8–10 subsequently decreasing slightly in length and increasing slightly in width; antennomere 11 elongate; antennomeres 3–11 covered in moderately dense, suberect pubescence.

Natural history. This Three Kings Islands endemic has primarily been collected by beating and sweeping vegetation, specifically from grasses and sedges. It has additionally been collected by sweeping kânuka.

Distribution. Offshore island : Three Kings Island (TH).

Type material examined. Holotype. Male ( NZAC), labeled: “ THREE KINGS IS NZ / Great I / 27 Nov 1983 / C.F. Butcher //ex. Grasses and / sedges // ‘Xylophilus’ luniger / Champion 1916 [male symbol] / det. S.E. Thorpe, 2002” . Paratypes (17). Offshore island . TH: Great Is , 27/11/1983, sweeping vegetation mainly Leptopermum ericoides, C.F. Butcher (3, NZAC) ; same, but, ex grasses and sedges (3, NZAC) ; Great Is , 11/1970, beating, J.C. Watt (1, NZAC) ; same, but without collecting method (1, NZAC) ; Great Is , Castaway Camp , 11/1970, G. Kushel (5, NZAC) ; same, but G. Ramsay, (4, NZAC) ; Great Is , North East I, 1/12/1983, J.C. Watt .

Figures

FIGURES 12A–E. Dorsal habitus images. (A) Zenascus antennalis (Broun), male; (B) Zenascus xenarthrus (Broun), male; (C) Zenascus roberti sp. n., male; (D) Zenascus luniger (Champion), male; (E) Zenascus incensum sp. n., male. Scale bars = 1.0 mm.

FIGURES 14A–J. Antennal illustrations for Zenascus species, male on left, female on right.(A) Z. coloratus; (B) Z. obscurus; (C) Z. aurum, sp. n.; (D) Z. nitidus; (E) Z. elenae, sp. n.; (F) Z. antennalis; (G) Z. xenarthrus; (H) Z. roberti, sp. n.; (I) Z. luniger; (J) Z. incensum, sp. n. Scale bar = 0.1 mm.

FIGURES 15A–C. Scanning electron microscope images of Zenascus species with close-ups of male antennomeres 7–9. (A) Z. roberti, sp. n.; (B) Z. luniger; (C) Z. incensum, sp. n.. Scale bars = 20μm.

FIGURES 19A–E. Scanning electron microscope images, Zenascus species, elytron, dorsal view. (A) Z. antennalis; (B) Z. xenarthrus; (C) Z. roberti, sp. n.; (D) Z. luniger; (E) Z. incensum, sp. n. Scale bars = 10μm.

FIGURES 20A–J. Scanning electron microscope images, ventral view of metafemora for Zenascus species. (A) Z. coloratus, male; (B) Z. obscurus, male; (C) Z. aurum, sp. n., male; (D) Z. nitidus, female; (E) Z. elenae, sp. n., male; (F) Z. antennalis, female; (G) Z. xenarthrus, male; (H) Z. roberti, sp. n., male; (I) Z. luniger, male; (J) Z. incensum, sp. n., male. Scale bars = 60μm.

FIGURES 22A–E. Abdominal ventrite illustrations for Zenascus species showing generalized punctation pattern. (A) Z. antennalis, male; (B) Z. xenarthrus, male; (C) Z. roberti, sp. n., male; (D) Z. luniger, male; (E) Z. incensum, sp. n., male.

FIGURES 23A–J. Male genitalia illustrations for Zenascus species. (A) Z. coloratus; (B) Z. obscurus; (C) Z. aurum, sp. n.; (D) Z. nitidus; (E) Z. elenae, sp. n.; (F) Z. antennalis; (G) Z. xenarthrus; (H) Z. roberti, sp. n.; (I) Z. luniger; (J) Z. incensum, sp. n.

FIGURES 24A–F. Scanning electron micrographs of gland pores on metafemur of Zenascus spp. (A) Z. aurum, sp. n.; (B) Z. antennalis; (C) Z. xenarthrus; (D) Z. roberti, sp. n.; (E) Z. luniger; (F) Z. incensum, sp. n. Scale bars = 2μm.

FIGURES 27A–D. Distribution maps. (A) Zenascus aurum, sp. n., Zenascus incensum, sp. n., and Zenascus xenarthrus, (B) Zenascus coloratus, (C) Zenascus elenae, sp. n. and (D) Zenascus luniger.