Contacyphon forcipatus, Zwick, Peter, 2015

Zwick, Peter, 2015, Australian Marsh Beetles (Coleoptera: Scirtidae). 8. The new genera Cygnocyphon, Eximiocyphon, Paracyphon, Leptocyphon, Tectocyphon, and additions to Contacyphon de Gozis, Nanocyphon Zwick and Eurycyphon Watts, Zootaxa 3981 (4), pp. 451-490 : 486-487

Contacyphon forcipatus , n. sp.

( Figs. 103–106 )

Type material: 1♂ Holotype: Jardine R. Xing 29 km S Bamaga N.Q. 28.Aug.–5.Sep.1985 E.N.Marks coll. ex light trap ( ANIC). 1♂ Paratype: Cow Bay N of Daintree, N.Qld. 7–20.ii.1984 J.C.Cunningham (QDPC-C).

Habitus. Oval, BL 1.7 mm, BL/BW ~1.5. HCW 0.6 mm, PW 0.8mm, PL 0.4 mm in midline. Rather convex. Pronotum anterolaterally rough through coarse granular punctures. The granular punctures in the centre of disc are very fine. Elytral punctation very fine. Uniformly yellow-ochre. Blond pilosity somewhat shaggy, almost erect.

Head very large, oral area narrow, labrum a small approximately square lobe with rounded margin. Mandible with wide cutting edge, no tooth. Terminal segment of maxillary palpus shorter than penultimate, slightly concave, distal half narrow, pointed. Labial palpus straight, with short, pointed terminal segment. Antennae slender, scape large, without sharp edge, pedicel much thinner, similar in length to antennomere 3. Legs unmodified.

Lower side. Head with well delimited small buttonhole. Prosternal process short, tear-shaped, mesoventral groove very short, transverse with angular, slightly projecting anterior margin. The rear margin is part of the regularly curved front edge of the mesoventrite, not angular as in most congeners. Mesoventral process fairly wide, caudally incised, separating the coxae completely and meeting the metaventral process. Metaventral discrimen not seen.

Male. T8 short, a tranverse arch supported by strong straight apodemes 3 times longer than the plate. S8 not developed. T9 unsclerotized, smaller than T8, apodemes shorter and thinner, a little curved. T8 and T9 are completely bare, no hairs or microtrichia. S9 is a narrow hairpin-like sclerite which first widens, then suddenly narrows and is longitudinally divided. Each distal part supports a large sharp barb and then tapers to a delicate tip ( Fig. 103 ).Tegmen and parameres form an elongate oval sclerite which is caudally narrowly open ( Fig. 104 ), each paramere with a sharp straight subapical spine appressed to the main sclerite. Penis ( Fig. 105 ) with large oval pala full of muscles attaching to the common sinew of a pair of long sinuous prosthemes that cross over each other. They are in a different position in the paratype ( Fig. 106 ) and can apparently be moved like scissor blades.

Female. Not known.

Note. The new species belongs to genus Contacyphon but close relatives are unknown. The lack of mandibular teeth and the rounded rear margin of the mesoventral groove are minor deviations from the common pattern and are possibly related to small body size. The fully developed but bare plates of T8 and T9, the modified narrow S9, and the shape of the penis are reminiscent of species in the apoanus -subgroup, e.g. C. rotundosternalis ( Klausnitzer, 2012) from Nepal and C. sagadanus ( Yoshitomi, 2009) from Luzon. However, their tegmen is a pilose plate very different from the unusual tegmen of C. forcipatus .

Etymology. The name is an adjective alluding to the shape of the genitalia: Latin forcipatus , provided with a forceps.

Figures

FIGURES 103 – 106. Contacyphon forcipatus, n. sp., male. 103, segments 8 and 9, superimposed; 104, tegmen; 105, penis (103 – 105, holotype); 106, penis and tegmen of the paratype, superimposed. All to the same scale.