Prionocyphon urbanus, Zwick, 2016

Zwick, Peter, 2016, Australian Marsh Beetles (Coleoptera: Scirtidae). 9. The relations of Australasian Ypsiloncyphon species to their Asian congeners, additions, mainly to Petrocyphon and Prionocyphon, and a key to Australian genera of Scirtinae, Zootaxa 4085 (2), pp. 151-198 : 176-179

Prionocyphon urbanus , n. sp.

( Figs 65, 66 , Table 2)

Type material. ♂ Holotype, 1♂ paratype: MV Ashfield [33°53'16'', 151°07'27''] New South Wales 15:12:1980 D.A.Doolan (AMS).

Habitus. BL 2.6 mm, BL/BW~1.7, HCW equals ~60% of BW. Elongate-oval, uniformly light brown. Punctures on head and pronotum fine, those on elytra distinctly larger but still relatively fine.

Male. Segments 8 and 9 as in Table 2. Tegmen a spacious pouch with simple tongue-shaped parameres without armature. The modified penis seems to be connected to the pouch. There is a short transverse sclerite ( Fig. 66 , ts) which represents both pala and transverse bridge. Curved parameroids with outwardly turned tips and a strong arm directed obliquely cephalad and mediad attach to its sides. The trigonium between parameroids shaped like a tough membranous funnel, but colourless and not easily recognized, slightly longer than parameroids, apex longitudinally divided. Basally, only sides are seen which attach near the anterolateral corners of the transverse penis sclerite (arrows in Fig. 65 ).

Wide endophallus projecting anteriorly beyond tegmen ( Fig. 65 ), armature consisting of lateral bands of slender spines. Density of spines varies, but a short anterior section, a long middle part, and a short caudal section distinguishable. Caudal section with smaller teeth beginning beyond a sparse transverse row of particularly large spines.

Styles attach to sides of tegmen base. During mounting, protraction of the macerated specimen reversed them, their delicate microtrichia therefore directed forward ( Figs 65, 66 ).

Female. Unknown.

Note. The caudal tip of the tough funnel confining the endophallus can open wide. Apparently, the funnel serves as a holdfast when the body fluid exerts pressure pushing the endophallus out of the tegminal pouch. During this process the endophallus turns inside out and the spines stand on the outside of the duct, as shown in the illustrations of a partly everted penis of P. storeyi ( Fig. 61 ) and P. quasichameleon ( Watts 2010b: fig. 38b).

P. urbanus and P. quasichameleon from Queensland are apparent sister species. The latter differs (from the original description) by more slender parameres and more slender parameroids which have inwardly turned tips. The arms of the parameroids are straight and extend cephalad, and their medial edges lie parallel to each other. The endophallus is longer, and the armature seems less dense.

Etymology. The Latin adjective urbanus , a city dweller, alludes to the type locality in suburban Sydney.

Figures

FIGURES 65 − 68. Male genitalia of Prionocyphon urbanus n. sp. (65; 66 diagrammatic) and P. deanboltoi (67; 68, enlarged detail of the horns at the penis apex). Abbreviations: de, endophallus; eph, endophallus; pd, parameroid; pe, paramere; st, style; te, tegmen; ts, transverse sclerite.

FIGURES 61 − 64. Prionocyphon storeyi Watts, male genitalia. 61, Mt. Tamborine, arrow points at delicate tip of stylus; 62, Mossman Gorge; 63, Mt. Spec, arrow pointing at scaly surface of retracted endophallus; 64, diagram showing the tegmen and its components in grey shade, for easier distinction from the penis and its components. Abbreviations: pa, pala; pd, parameroid; pe, paramere; st, stylus; te, tegmen; tr, trigonium. Not to scale.