Prionocyphon uncatus, 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 : 172-174

Prionocyphon uncatus , n. sp.

(Figs 48−53, Table 2)

Type material. Holotype ♂, 1 paratype ♀: Black Mtn, light trap, ACT, 13.1.69, S.Misko ( ANIC).

Additional paratypes: 1♂: Black Mtn, ACT, 22.ii.1965 T.F.B. Common; 1♂: ibidem, 29.11.68, M.S.Upton (all ANIC). 1♂: Mittagong, N.S.W. Lea (SAMA).

Habitus. Stout, compact, rather convex, widest before midlength, narrowing a little caudally, almost dropshaped. BL 2.1−2.6 mm, BL/BW ~1.55, HCW equals ~60% of BW. Dorsal side, base of antennae and legs uniformly brownish, head darker than rest, flagellum infuscate. Punctures on head and pronotum very fine, fine on FIGURES 48−53. Prionocyphon uncatus n. sp., male (48−52) and female (53). 48, T8 and S8; 49, T9; 50, S9; 51, penis and tegmen, superimposed; 52, apex of same, beginning eversion of endophallus; 53, bursal sclerite. 48–50 to the same scale, 52 not to scale.

Male. Antenna serrate near base, distal flagellar antennomeres triangular. Pilosity of abdominal sternites heterogenous. Plate of T8 wide, barely longer than apodemes, caudal edge truncate, with setae and microtrichia, S8 a shallow thin sclerite arch (Fig. 48). T9 has longer apodemes but a smaller plate than T8 which is relatively well defined, caudally truncate, bare (Fig. 49). S9 large, caudally bilobed and pilose, its anterior portion supported by a thin loop-shaped sclerite (Fig. 50).

The hairless tegmen (Fig. 51) with a deep keyhole-shaped basal notch surrounded by a strong sclerite. Styles long and slender. Parameres with convex convergent sides, ending in a strongly sclerotized dark hook with sharp tip. Transparent dorsal and ventral flanges surround the long parallel penis. Pala rounded in front and more than twice as long as the section occupied by parameroids and trigonium (Fig. 51).

Trigonium with wide base, diameter decreasing stepwise to a long narrow tip. Parameroids a little shorter than trigonium, with hooked apices overlying membranous cone through which ejaculatory duct can apparently be extruded. Orientation of parameroid apex changes with condition. At rest, tips directed mediad (Fig. 51). When penis apex spread open, parameroid tips turn outward (Fig. 52). At the same time, two slender bacula and two triangular sclerotized areas become exposed on spreading membranous penis apex. Armed endophallus apparently absent, visible parts of wall of wide ductus bare.

Female (presumed). Antenna unmodified, distal flagellar antennomeres indistinctly conical, barely longer than apically wide. S6 with central porus. A prehensor was not recognized. Bursal sclerite consisting of a funnel-shaped sclerotized section of the gonoduct, the sides diverge cephalad and appear reticulate. Between their rear ends lies an elongate plate, between their divergent front ends are some small asymmetrical sclerites (Fig. 53) resembling female morphotype A ( Figs 45, 46 ).

Etymology and note. The presumed female was taken together with several males, and there were no additional species in the sample. The Latin adjective uncatus means hooked, the same as hamatus . Both names describe the apex of the tegmen. Prionocyphon hamatus Watts and P. uncatus n.sp. are related but different species with serrate antennae. Prionocyphon hamatus differs mainly by the almost equal lengths of the pala and the distal portion of the penis, and the longer and more slender trigonium, the straight parameroids, and the long and thin paramere apices which were described as “resembling the hook on the apex of the penis in P. storeyi ” ( Watts 2010b). They are apparently not strongly sclerotized while this is the case in P. uncatus .

Figures

FIGURES 45 − 47. Prionocyphon spp., bursal sclerites, front end at top of page. Morphotypes A (45, 46) and B (47): 45, Acacia Plateau N. S. Wales H. Davidson (ANIC); 46, Tasmania A. Simson (SAMA); 47, Star Valley Lookout c. 5 km W of Paluma QLD 3. vii, 67 at light J. G. Brooks (ANIC). The scale lines are 100 µm.