Ypsiloncyphon angustus, Zwick, Peter, 2014

Zwick, Peter, 2014, Australian Marsh Beetles (Coleoptera: Scirtidae). 6. Genera Calvarium Pic, Papuacyphon Zwick, and Ypsiloncyphon Klausnitzer, Zootaxa 3846 (1), pp. 1-41 : 36-37

Ypsiloncyphon angustus , n. sp.

( Figs. 121–126 )

Type material. QLD: Holotype ♂: “Big Mitchell Ck., Mareeba-Molloy Road, N.Qld., 4 May 1967, D.H.Colless” ( ANIC). Paratypes: 1♂ 1♀, same data as holotype; 1♂ 2♀: “Bamboo Ck., near Miallo N. of Mossman N.Qld. 25 Apr. 1967 D.H. Colless”; 1♂ 1♀: “ 7-14 km W of Herberton via Watsonville N. QLD 1 May 1987 D.H.Colless”; 1♂: “ 12.40S 142.40E QLD Batavia Downs Hmstd. 17-23.Jun.1992 T.Weir at light”; 1♂: “ 17.41S 145.26E, Millstream Falls Nat.Pk., Q., 24–25 May 1980, I.D.Naumann, J.C.Cardale”; 1♂: “Kuranda Range State Forest N.Qld. 20 April 1967, D.H.Colless”; 2♀: “Rocky Ck., 7 M. N of Atherton N.Qld. 3 May 1967 D.H.Colless”; 1♀: “ 16.03S to 16.05S 145.28E Cape Tribulation area QLD 21–28Mar.1984 A.Calder & T.Weir” (all ANIC). 1♀: “C.Q.: 19°44'Sx 147°45'E, C.Upstart, Shark Bay, 5m, 24 Apr. 1998 G.Monteith, Pyrethrum trees 5764”( QMSB, T189939). 1♀: “N. Queensland, Blackb's coll.” ( SAMA).

Habitus. ♂ BL 1.7–1.9 mm, BL /BW ~1.7; ♀ BL 1.6–1.9 mm, BL /BW ~1.8. Black, legs and antennae yellowish.

Male. Apodemes of T9 on average 2.1 (1.8–2.5; n=8) times longer than those of T8. S9 about as long as penis (90–110% penis length; n=7), both blades of similar length, gradually narrowed to regularly curved apices, tip of the shorter right hand blade curved a bit to the outside. The capulus is anteriorly barely widened, its length equals about 70% of the length of the pala which itself corresponds to 1/3 of total penis length ( Fig. 121 ). Pala anteriorly wide, truncate, waisted to about half penis width and almost immediately expanded again towards the base of trigonium and parameroids. Widest part of penis hardly wider than the large front end of the pala. Trigonium narrow, basally about parallel-sided, then gradually restricted to the very thin distal half. The tip is often bent ventrad. Apices of parameroids similarly narrow, parallel-sided, medial edge straight, tips blunt ( Fig. 123 ). In oblique view, the parameroids and the trigonium curve in opposite directions ( Fig. 122 ). Tegmen parallel-sided, anteriorly not widened, the narrow parameres end in long thread-like tips (not shown).

Female. Microtrichial fringe along caudal edge of T7 medially interrupted. In front of this gap is a soft area with reduced pilosity from which rise two minute erect sclerites ( Fig. 125 ). Apodemes of S8 short, in front forming a wide arch with lateral expansions. These are largest furthest in front, while the middle of the arch remains thin. T8 and ovipositor as for genus. Vulvar sclerite a long semi-tube, the front drawn out into elongate ends ( Fig. 124 ). Dictyon large, over 20 meshes, the largest one with 4 distinct marginal outgrowths ( Fig. 126 ).

Notes and etymology. The relatively stout pala and the female S8 suggest a close relationship with Y. brevis . The Latin adjective angustus (narrow) describes the narrowness of several components of the long male genitalia, and the corresponding narrowness and length of the vulvar sclerite. The modification of female T7 is unique. Ypsiloncyphon angustus is restricted to tropical North Queensland. There is limited overlap with the related Y. brevis , e.g., in the Atherton Tableland.

Figures

FIGURES 121 – 126. Ypsiloncyphon angustus, n. sp.: 121, male S 9; 122, penis, dorsolateral (near Herberton); 123, penis, dorsal (Big Mitchell Ck); 124, female terminal segments with vulvar sclerite, apodemes of S 8 black, expansions grey (Rocky Ck); 125, female, tip of T 7; 126, dictyon. Figs. 121 – 123 to the same scale, 125 not to scale.