Epuraea glabrata, Jelínek & Leschen & Hájek, 2017

Jelínek, Josef, Leschen, Richard A. B. & Hájek, Jiří, 2017, Revision of Epuraea of New Zealand (Coleoptera: Nitidulidae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 57 (2), pp. 617-644 : 626-629

Epuraea glabrata sp. nov.

( Figs 3–4 , 19–24 )

Type locality. Capleston, Buller, South Island, New Zealand.

Type material. HOLOTYPE: J ( NZAC), ‘ NEW ZEALAND [p] BR [hw] / Flowers Ck. / Capleston / 12 Nov 1971 / J.C. Watt [hw] // Fungus / 71/152 [hw] // Beech Forest / Utilization / Project [p] // Epuraea /sp.n. [hw] / det. R.A.Leschen [p] // HOLOTYPUS / Epuraea / glabrata sp. n. / Jelínek, Leschen / et Hájek det. [p, red label]’. PARATYPES: NORTH ISLAND: BP: 1 ♀, ‘Para- / type [p, round label with yellow border] // 4. [?, illegible, hw] // Rotorua [?, illegible, hw] // New Zealand [p, underlined with red] / Broun Coll. / Brit. Mus. / 1922-482 [p] // PARATYPUS [p] / Epuraea / glabrata sp.n. [hw] / Jelínek det. 19 [p] 72 [hw, red label]’ ( BMNH). GB: 3 JJ 2 ♀♀, ‘ NEW ZEALAND GB / L. Waikaromoana / 3 Mar 1983 / CF Butcher [hw] // bark of / N. menzies. [hw]’ ( NZAC). WN: 1 ♀, ‘ Day´s Bay / 9.10. [19]38 / G.B.Rawlings [hw] // E. S. Gourlay / Acc. 1970 / Ent.Div. [p] // Epuraea / sp. nov.? [hw] // Entomology Div. / D.S. I.R. /New Zealand [p]’ ( NZAC) ; 1 J, ‘New Zealand WN / Pakuharaki Fork / Kaitoke / 09-Nov-96 [p] // Under flake of bark, / bole of beech tree / with sooty mould [p]’ ( NZAC). WO: 1♀, Okauia 29.12.[19]47/ Brookes Fungus [hw] // A.E.Brookes / Collection [p] // Entomology Div. / D.S. I.R. / New Zealand [p]’ ( NMPC). SOUTH ISLAND: BR: 2 JJ, ‘ NEW ZEALAND, BR / Flowers Ck / Capleston / 19 Nov 1971 / J. C. Watt // fungus / 71/152 [hw] // Beech Forest / Utilisation / Project [p]’ ( NZAC). KA: 1 J, ‘ NEW ZEALAND, KA, / Mt Fyffe , Hinau Tk, 22 March 2015, / R. Leschen, E. Hilario, sooty mould at night, / 42 21.055 S, 173 34.073 E, 177 m, RL1839 [p]’ (specimen in ethanol, NZAC). NC: 3 JJ, ‘ NEW ZEALAND NC, Nina / Valley, beech forest / -42.5223, 172.3907 / 14.iii.2014 A. M. Hoover / Hand Coll ex. ant nest [hw]’ [two Prolasius advenus (Fr. Smith, 1862) ants pointed below 2 spec., one ant pointed below another] ( LUNZ). NN: 2 JJ, ‘ NEW ZEALAND: S-Isl. NW / Richmond Forest Park / Mt. Beeby Track, 7 km S / Kikiwa // Motupiko River Valley / 9.2.1997 Schuh & Lang / Notofagus leaf litter [p]’ ( NMPC, RSCW). SD: 2 JJ, ‘Picton, [p] / 30-31 – 3 – 35 [hw] / E. S. Gourlay [p] // E.S.Gourlay [p] // E. S. Gourlay / Acc. 1970/ Ent.Div. [p]’ ( NZAC) ; 1 J, ‘ Picton [p] / 24-3-[19]35 [hw] / E.S.Gourlay [p] // E. S. Gourlay / Acc. 1970 / Ent. Div. [p] // Epuraea / sp. nov.? [hw] // Entomology Div. / D.S. I.R. / New Zealand [p]’ ( NZAC). SI: 1 ♀, ‘ New Zealand SI / Stewart I / Codfish I / Valley Track / 26Nov 1981 [p] // B. A. Holloway / on tree trunk [hw]’ ( NZAC). WD: 1 J: ‘ NEW ZEALAND, WD, / Gillespies Beach Rd, 22 Mar 2017, / C. Carlton, R. Leschen, B. Owens, RL1944, / sifting, 43 25.40S, 169 53.11E [p]’ (specimen in ethanol, NZAC). Unknown: 1 ♀, ‘Para- / type [p, round label with yellow border] // sp. [hw] // 21-4-[19]16 // New Zealand [underlined with red] / Broun Coll. / Brit. Mus. / 1922-482 [p] // PARATYPUS [p] / Epuraea / glabrata sp.n. [hw] / Jelínek det. 19 [p] 72 [hw, red label]’ ( BMNH) ; 1 ♀, ‘Para- / type [p, round label with yellow border] // New Zealand [underlined with red] / Broun Coll. / Brit. Mus. / 1922-482 [p] // PARATYPUS [p] / Epuraea / glabrata sp.n. [hw] / Jelínek det. 19 [p] 72 [hw, red label]’ ( BMNH) ; 1 ♀, ‘near / 303 [hw] // 2.4.[19]16 [hw] // T. Broun / Collection [p] // A. E. Brookes / Collection [p] // Epuraea / sp. nov.? [hw] // Entomology Div. / D.S. I.R. / New Zealand [p]’ ( NZAC) .

Description. Male holotype. Oblong oval, convex with broadly explanate sides, apparently smooth and shining ( Fig. 3 ). Unicolorous, yellow brown. Pubescence light, recumbent, thin and short, indistinct; particular setae not reaching base of following ones.

Head narrower than anterior margin of pronotum (ratio WPR3/HEAW: 1.18). Clypeus moderately convex, anterior margin truncate, not bordered. Frons flat with pair of round impressions above antennal insertions. Eyes small, regularly convex, temples rectilinear, converging posteriad. Punctures of frons markedly smaller than eye-facets, separated by 1–2 diameters, interspaces obsoletely alutaceous (magnification 50×), shining. Antennae almost as long as width of head across eyes (ratio ANLE/HEAW: 0.94), antennal club occupying approximately 1/3 of antenna length, oval, approximately 1.25× longer than wide ( Fig. 19 ). Ratio length/width of antennomeres I–XI: 1.43: 1.48: 2.40: 1.11: 1.48: 1.00: 0.66: 0.43: 0.45: 0.66, respectively.

Pronotum transverse, widest behind its midlength (ratio WPR2/LEPR = 2.00), distinctly narrowed both anteriorly and posteriorly (ratio WPR1/WPR2 = 0.90; WPR2/WPR3 = 1.70), at base distinctly wider than base of elytra. Anterior margin with deep trapezoidal emargination, not bordered. Anterior angles broad, prominent, obtusely rounded with indistinct tips. Lateral margins arcuate, with indistinct rim and with inconspicuous fringe of dense short setae; sides broadly explanate-reflexed, at midlength almost as wide as antennal club, gradually narrowed anteriad and dilated posteriad. Basal margin in front of scutellar shield subtruncate, not bordered, besides posterior angles broadly and shallowly arcuately emarginate; posterior angles obtuse, not prominent. Pronotal disc transversely convex. Punctures similar to those of frons, separated by 2–3 diameters; interspaces on disc with obsolete rudiments of microsculpture, shining, on explanate sides densely microscopically punctate, dull. Scutellar shield subtriangular with rounded apex, punctures separated by 1.0–1.5 diameters, interspaces microscopically punctate.

Elytra ovate, widest near basal fourth, gradually narrowed both anteriad and – more strongly so – posteriad; elytral apex rounded. Ratio LELY/WELY = 1.04. Base distinctly narrower than that of pronotum, ratio WELY/WPR2: 1.00; humeral angles obtusely rounded, sides explanate-reflexed, approximately as wide as explanate pronotal sides near anterior angles, lateral margins broadly arcuate, finely rimmed and fringed like on pronotum. Punctures and microsculpture similar to pronotum.

Pygidium broadly truncate apically, with rudimentary pubescence and fine distinct punctures separated by about one diameter, interspaces smooth, shining. Tergite VIII exposed, large, broadly rounded apically.

Ventral part. Postmentum flat, microscopically alutaceous, dull with widely spaced shallow indistinct punctures.Antennal furrows straight, broad, with distinct outer margins, converging posteriad, widely separated in middle. Genae (ventral side) densely shallowly punctate and microscopically punctate, dull, with long recumbent setae.

Prosternum transversely convex with indistinct shallow and obsolete punctures, feebly shining. Prosternal process strongly longitudinally convex between procoxae (in lateral view), posterior to procoxae depressed, almost semicircular ( Fig. 20 ). Broad flat hypomera with dense micropunctures, dull, with indistinct obsolete and widely spaced punctures. Mesoventrite transversely convex, obsoletely punctate and feebly shining like prosternum, posterior margin of prepectus obsolete, broadly interrupted in middle. Elytral epipleura concave, in basal portion as wide as mesocoxa, sharp rim of inner margin ends abruptly at 5/7 of elytral length.

Metaventrite flattened in middle, with fine, not-impressed discrimen present. Punctures small and shallow, separated by approximately 1.0–1.5 diameters, interspaces microscopically punctate, feebly shining. Anterior intercoxal margin subtruncate, posterior one arcuately emarginate. Mesocoxal lines running close to posterior mesocoxal margins and ending in anterolateral corners of metaventrite, recurrent lateral portions not developed, axillary spaces absent.

Punctuation and sculpture of abdominal ventrites similar to metaventrite. Abdominal ventrite I as long as metaventrite along median axis, metacoxal lines closely bordering metacoxal cavities. Abdominal ventrites II–IV subequal, combined length shorter than I. Hypopygium broadly rounded, more distinctly microscopically punctate and duller than preceding ventrites.

Distances between pro-, meso- and metatibiae as 1.00: 1.50: 3.75. Femora slender, oblong oval, inner margin shallowly concave in distal third. Mesofemur longer than profemur (ratio LFE1/LFE2: 0.90), meso- and metafemur subequal. Ratios LFE1/WFE1: 3.0, LFE2/WFE2: 3.33, LFE3/WFE3: 3.40. Tibiae straight, slender, simple, outer subapical angle rounded, inner one with pair of short subequal spurs. Ratio LTI1/WTI1: 4.0, LTI2/WTI2: 5.37, LTI3/ WTI3: 6.87. Protarsomeres I–III dilated, bilobed, 0.5× width of protibia; protarsomere V as long as I–IV combined; tarsal claws simple. Meso- and metatarsomeres I–III narrower, 0.5× width of tibia, moderately bilobed.

Male genitalia. Lateral lobes of tegmen with sickle-shaped tips curved inwards ( Fig. 21 ), median lobe gradually narrowed towards bluntly pointed apex ( Fig. 22 ). Conspicuous armature of endophallus consists of two parallel series of strong acute spines ( Fig. 23 ).

Female. Same as male, except as follows. Yellow-brown, disc of pronotum and of each elytron infuscate to black-brown, legs and antennae brown-yellow ( Fig. 4 ). The difference between the width of pronotum and elytra less conspicuous than in male, but distinct (ratio WELY/WPR2: 1.03–1.05 in males, 1.01–1.03 in females). Elytra comparatively longer, reaching their maximum length at suture; ratio LELY/WELY: 1.17–1.19. Apex of pygidium broadly rounded apically. Ovipositor as depicted in Fig. 24 .

Measurements. Body length 3.2–3.9 mm (holotype 3.2 mm), width 1.7–1.8 mm (holotype 1.7 mm). Ratio WPR1/WPR2: 0.89–0.92; WPR2/WPR3: 1.63–1.71; WPR2/LEPR: 1.87–2.00. Differential diagnosis. With oblong oval and moderately convex body form, broadly truncate terminal labial palpomere, transversely oval prosternal process posterior to procoxae, axillary spaces on metaventrite absent, slender legs and antennae simple (not bilobed) metatarsomeres I–III and acute/acuminate tips of female elytra, the new species is apparently similar to the endemic New Zealand species E. antarctica and E. signata , from which it differs in the broadly and abruptly explanate-reflexed sides of pronotum, pronotal base distinctly wider than base of elytra, punctures of dorsal surface hardly distinct and separated by several diameters, and rudimentary dorsal pubescence which is short and indistinct.

Etymology. Latin adjective glabratus, -a, -um (= somewhat smooth, glabrate), referring to the rudimentary punctation and pubescence of dorsal surface.

Notes. The broadly explanate body form distinguishes E. glabrata sp. nov. from the remaining species in New Zealand, and due to its sparse collecting records from across much of the country, it is possible that this species has a rather specialized life history. Most specimens have been taken from Nothofagus bark, and often in association with sooty molds. The specimens collected by J. C. Watt with collection number ‘71/152’ have additional information contained in the NZAC litter logbook with the following information: ‘4½ SE of Capleston, sooty fungus on trunk of Nothofagus fusca ’. The association of E. glabrata with beech trees, though, is not consistent, because specimens have been collected in areas where Nothofagus presently does not exist, like parts of Westland and Stewart Island, though sooty molds are widespread and occur on other tree hosts, like tea tree (genus Leptospermum ). Many associates of sooty molds tend to be rather common, like Hisparonia hystrix (Sharp, 1876) ( CARLTON & LESCHEN 2007) , and the single collection made from ants does not affirm inquilinism, a rare behavior in New Zealand beetles ( NOMURA & LESCHEN 2015). Additional collecting observations and gut content analyses are needed to clarify the exact habitat association, diet, and biology of E. glabrata .

Distribution: North Island: BP, GB, WN, WO. South Island: BR, KA, NC, NN, SD, SI, WD.

Figures

Figs 1–4. Dorsal habitus of New Zealand Epuraea species. 1 – E. antarctica (White, 1846) J, Buller Gorge (3.2 mm); 2 – E. antarctica ♀, Mt. Hutt (3.2 mm); 3 – E. glabrata sp. nov. J, Richmond Forest Park (3.3 mm); 4 – E. glabrata sp. nov. ♀, Okauia (3.6 mm).

Figs 19–24. Details of Epuraea glabrata sp. nov. 19 – antenna; 20 – prosternal process; 21 – tegmen; 22 – median lobe of aedeagus; 23 – armature of endophallus; 24 – ovipositor. Scale bar = 0.5 mm.