Zenascus luniger (Champion) 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 : 39-40

Zenascus luniger (Champion) , comb. n.

Figs 12D , 14I , 15B , 19D , 20I , 22D , 23I , 24E , 27D

Xylophilus luniger Champion, 1916: 47–48 , pl. 2, Figs 25, 25a ; Maddison, 2010: 428.

Diagnosis. This species is distinguished from congeners by the biseriate pubescence of the pronotum and elytra, the slightly impressed basal pronotal fovea, and the highly modified antennomeres 7–9 of males. Zenascus luniger is most easily confused with Z. incensum , but males can be distinguished from one another based on the specific modifications to antennomeres 7–9 ( Figs 15B & 15C ) and the presence of a transverse ridge on the head of Z. incensum . Currently, morphological differences between females of these two species have not been observed but can be identified based on biogeographic distribution. Specimens of Z. luniger have only been collected from the North Island of New Zealand, whereas specimens of Z. incensum have only been collected from the Three Kings Islands.

Description. Length 1.51–1.82 mm. Head, scape, and antennomeres 7–11 piceus to rufo-testaceous; pronotum piceus to rufo-testaceous; antennal pedicel, antennomere 3–6, and elytra, brunneus to golden. Dorsal integument matte, vestiture biseriate, one decumbent, thin, short seta arising anerad of each puncture, length about equal to 3× puncture length, with 2–3 additional short, decumbent setae between each pair of punctures, length about 2/3× primary seta. Ventral vestiture similar to dorsum, biseriate. Head, HW 0.47–0.51 mm, HL 0.21–0.23 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. Antennae with distance between antennal insertions narrow, approximately equal to diameter of 2.5 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, shorter than antennomere 4; antennomere 4 approximately 3× length of antennomere 3, longer than antennomere 5; antennomere 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 rounded, with apex of inner branch connecting to remaining antennomeres, with apex rounded; antennomere 8 laterally expanded with basal appendage projecting back towards antennomere 7, projection apex rounded; antennomere 9 with modified outer apex, projecting anteriorly, apex rounded, with dense pilosity extending behind; antennomere 10 subquadrate; 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 0.36–0.39 mm, PL 0.32–0.36 mm, subquadrate, width slightly greater than length, width 1.09–1.13× length; pronotal width 0.55–0.70× elytral width, pronotal width 0.72–0.77× head width; sides slightly rounded, posterior angles rounded; disc with two slightly impressed basal fovea, a slight transverse sulcus just anterad of center; punctation consisting of deep, small elongate punctures, unevenly spaced, more sparse basally and laterally. Elytra 1.89–2.33× longer than wide and 3.72–3.82× longer than pronotal length, EW 0.51–0.69 mm, EL 1.19–1.31 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 postero-ventral face, overlying slight excavation along entire 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 greater than length at midline; deep punctures confined to abdominal process and 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, lateriall delimited from apicale, without distinct sclerotization; 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 1.72–1.82 mm, HW 0.45–0.48 mm, HL 0.18–0.22 mm, PW 0.41–0.42 mm, PL 0.35–0.39 mm, EW 0.81–0.83 mm, EL 1.37–1.43 mm. Head very slightly impressed and 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.

Remarks. This species was not included in Hudson (1934). It was located as a pair by Champion (1916) in D. Sharp’s collection presumably sent by Broun, labeled with a manuscript name in the corylophid genus Sacium LeConte from Moko Hinou Island. In order to stabilize this name, a lectotype and one paralectotype are here designated from the material of Xylophilus luniger located in the BMNH.

Natural history. This is a relatively uncommon species distributed in the North Island. This species has been collected by beating vegetation, specifically Metrosideros excelsa Sol. ex Gaertn. and Phormium tenax .

Distribution. North Island: Northland (ND), Auckland (AK), Coromandel (CL), and Bay of Plenty (BP).

Type material examined. Lectotype, male ( BMNH): “[male symbol] // Moko Hinou / isld [handwritten] // Sharp Coll. / 1905-313. // 12 // Type / H.T. [red circle label] // Xylophilus / luniger, Ch , / [male symbol] [Champion handwriting] // Sacium ochraceum [handwritten] // Sp. figured. // LECTOTYPE [male symbol] / “ Xylophilus ” / luniger / Champion / det. J.C. Watt / 1985” . Paralectotype, female ( BMNH): “[female symbol] // Sharp Coll. / 1905- 313. // Type / H.T. [red circle label] // Moko Hinou / Island [Champion handwriting] // Xylophilus / luniger Ch. / [female symbol] [Champion handwriting] // PARALECT. [female symbol] / “ Xylophilus ” / luniger / Champ / det. J.C. Watt / 1985” .

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.

FIGURE 25. One of two most parsimonious trees recovered from Maximum Parsimony (MP) phylogenetic analysis based on 19 morphological characters for the New Zealand species of Zenascus. (L = 39; CI = 0.61; RI = 0.72). Numbers above branches indicate Bremer (Decay index) support values.

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.