Gymnanthelius hieroglyphicus (Deane)

Perkins, Philip D., 2004, A revision of the Australian endemic water beetle genus Gymnanthelius Perkins (Coleoptera: Hydraenidae), Zootaxa 585, pp. 1-39 : 18-20

Gymnanthelius hieroglyphicus (Deane)

( Figures 7 , 14 , 23 )

Ochthebius hieroglyphicus Deane, 1933: 20 .

Gymnanthelius hieroglyphicus, Perkins 1997: 139 .

Type Material. Holotype (by monotypy; female): Australia, N.S.W., Allyn River; deposited in the ANIC.

Diagnosis. Recognized by the random punctures on the elytral disc, with interstices shining, the non­discal punctures subserial or serial. Most similar to G. t u n i c u s, but size smaller (ca. 1.75 mm vs. 2.08 mm), lateral elytral punctures not as randomly arranged and not as deeply impressed, and the dorsal coloration less deeply black; differing also in aedeagal structure ( Figs. 14, 16 ).

Description. Holotype 1.75 x 0.83; head length 0.38, width 0.48; pronotum midlength 0.45, maximum width 0.59 just behind anterior angles; elytra length 1.08, maximum width 0.83. Form moderately ovate, transversely quite convex. Dorsum dark brown or black with faint cupreous reflections, legs brown, venter dark brown.

Eyes moderately large, in dorsal aspect 9 convex facets in longest series. Clypeus and frons mcr., dull, coarsely moderately densely punctate, punctures on clypeus largest, c. 1.5x eye facet, interstices c. 1x puncture diameter; each puncture on disc with short very indistinct recumbent seta. Frons interocular foveae deeply impressed, longitudinal; midlongitudinal weak carina behind median relief. Ocelli very indistinct. Labrum in male anteriorly produced in two weakly reflexed lobes separated by U­shaped median emargination, each lobe slightly longer than last maxillary palpomere, setae distinct on disc, laterally forming narrow fringe; in female lobes slightly shorter, not reflexed. Mentum moderately coarsely sparsely punctate, interstices shining.

Pronotum anterior margin evenly arcuate between produced anterior angles, hyaline border well developed. Lateral depression four times as wide anteriorly as posteriorly, side emarginate before tooth­like posterior angle. Lateral hyaline border well developed, anterior extreme nearly attaining anterior angles, continuing in rather uniform width along sides, widest just behind lateral depression, in dorsal aspect margin oblique to midline, nearly straight except slightly indented opposite tooth­like posterior extreme of lateral depression. Lateral fossulae deep, inner margin abrupt, outer margin obsolete; without anterior or posterior pit. Disc transversely only moderately convex, gradually widening from anterior to about middle, then sides converging but only very slightly so to base; densely coarsely punctate, punctures c. 1x eye facet, interstices dull, effacedly mcr., c. 0.5– 1 x puncture diameter. Median groove mcr., rather wide, slightly constricted in middle, slightly wider in anterior than posterior 0.5, each end tapering and not attaining respective hyaline border. Anterior foveae shallow but distinct, punctate, each slightly wider than median groove at same level, separated from median groove by c. 1x fovea width, margins ill­defined. Posterior foveae absent or location only faintly indicated by slightly denser punctures.

Elytra widest at middle, sides regularly arcuate; explanate margin in male narrower than, in female as wide as metatibia, declivous, surface flat or only slightly transversely convex, origin just behind anterolateral angles, becoming obsolete near posterior 0.2, without discernable setae. Apices in male separately narrowly rounded, in female conjointly sharply rounded or subtruncate. Transversely quite convex, lateral and posterior declivity abrupt. Elytral punctures very large, c. 2– 3 x size of largest pronotal punctures, on disc very dense and random, interstices very narrow, convex, effacedly mcr., more shining than pronotal interstices; series 1 (sutural) and 10 each serially arranged, punctures of 10 distinctly deeper and larger than other elytral punctures; "series" 2–9 each appearing as if a very irregular interdigitating double row, hence elytra give impression of being derived from more than 10 series. Each puncture bearing short subdecumbent seta.

Metasternum median area in posterior 0.66 glabrous, shining, otherwise metasternum dull and hydrofuge pubescent. Abdominal sternites (microslide): 1–4 dull, completely hydrofuge pubescent, 5–7 shining, sparsely pubescent; 1–2 laterally bearing sparse spiniform setae; in male sternite 7 narrowly midlongitudinally glabrous, otherwise bearing dense long tapering setae, apical margin truncate; in female sternite 6 glabrous in basal 0.5, apical 0.5 with sparse setae, sternite 7 disc with dense tapering setae, glabrous laterally and narrowly basally, posterior margin truncate. Apical tergum in both sexes apically weakly truncate. Tibiae moderately stout.

Aedeagus: Length 0.40 mm.; mainpiece gradually increasing in width distally, apex asymmetrical, truncate; distal part of internal tube club­shaped; parameres with longest seta of apical pair relatively elongate, three times length of shorter seta ( Fig. 14 ).

Material Examined. New South Wales, Khancoban Creek, Khancoban, 1000 ft., 36° 9' S, 148° 12' E, 1 April 1965, M. E. Bacchus (MEB 230) — (40 BMNH). Representative specimens deposited in ANIC and MCZ.

Distribution. Currently known from two localities in New South Wales ( Fig. 23 ).

Notes. The habitus illustration given by Deane (1933:21) is entirely misleading with respect to the configuration of the sides of the pronotum; also the anterior discal foveae are not illustrated.

Figures

FIGURE 7. Gymnanthelius hieroglyphicus holotype. Dorsal and lateral habitus.

FIGURES 14 – 17. Gymnanthelius aedeagi. — 14. G. hieroglyphicus (specimen from NSW, Khancoban). — 15. G. po rc h i (holotype). — 16. G. tu nic u s (holotype). — 17. G. maxipunctus (holotype).

FIGURES 22 – 25. Gymnanthelius geographical distributions. — 22. G. opacicollis. — 23. G. hieroglyphicus. — 24. G. t u n i c u s. — 25. G. maxipunctus.