Hydraena simplicicollis Blackburn, 1896

PERKINS, PHILIP D., 2007, A revision of the Australian species of the water beetle genus Hydraena Kugelann (Coleoptera: Hydraenidae), Zootaxa 1489 (1), pp. 1-207 : 24-25

Hydraena simplicicollis Blackburn, 1896

( Figs. 29, 30 , 33, 34 , 249)

Hydraena simplicicollis Blackburn, 1896: 261 .

Hydraena simplicicollis ; Zwick, 1977: 175.

Type Material. Lectotype (male): Northern Territory, Macdonnel Ranges, Reedy Creek [labels: Lectotype [written on card with specimen] // Reedy Cr. // Aedeagus drawn by P. D. Perkins // Central Ausl. coll. Horn Exp. Pres. 7-97 // HYDRAENA simplicicollis, Blackb. // Type // Lecto & Paralectotype design. by P. Zwick, 1972 // DIGITAL IMAGE captured 2004 P. D. Perkins // LECTOTYPE T-13135 Hydraena simplicicollis Blackburn, 1896 ]. Deposited in the MVMA.

Differential Diagnosis. Very similar in habitus to H. brittoni ( Figs. 29–31 ); differing therefrom by the slightly wider mesoventral process (compared to the plaque width), the slightly more widely separated plaques, and the slightly coarser dorsal punctation. Reliable determinations will be based on examination of the aedeagi ( Figs. 33–36 ).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.59/0.70; head 0.24/ 0.37; pronotum 0.39/0.52, PA 0.42, PB 0.48; elytra 0.95/0.70. Head dark brown to piceous, pronotum and elytra brown, anterior and posterior margins of pronotum slightly lighter, legs and palpi yellowish.

Frons punctures ca. 1–2xef; interstices shining, 0.5–2xpd. Clypeus microreticulate laterally, finely sparsely punctate medially. Mentum shining, very finely sparsely punctate; postmentum microreticulate. Genae raised, lacking posterior ridge. Pronotal punctures on disc ca. 1–2xpd those of frons, interstices shining, 2–4xpd, punctures denser at anterior, a few separated by narrow walls; PF1 and PF4 absent; PF2 very small, nearly absent; PF3 moderately deep.

Elytral punctures about equal size of largest pronotal punctures. Intervals not raised, shining, width about 1xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins form moderately strong angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 1/.2/2.2/1. P1 laminate; median carina slightly angulate in profile. P2 moderately wide, l/w ca. 3/4, sides parallel, apex blunt. Plaques located in posterior 7/10 of metaventrite on sides of deep median triangular depression, plaques very narrow, straight, converging, anteriorly very narrowly separated. No midlongitudinal carina between mesoventral intercoxal process and plaques. AIS flat, width at arcuate posterior margin 1.5x P2. All tibiae simple, slender. Last sternite very slightly asymmetrical; last tergite with very small, slightly off-center concavity.

Aedeagus ( Figs. 33, 34 ) main-piece with long pointed process on right side about equal in length to right paramere, which is behind it; distal piece with several diagnostic processes; left paramere moderately wide in distal 1/2, four short, stout, arcuate setae at apex, setae along ventral margin sparse, long, and thin; right paramere somewhat knife-shaped, setae in row on ventral margin. Female last tergite with deep apicomedian incision delimiting two lobes, setae slender, tapering.

Distribution. Rather widely distributed in eastern Queensland, plus some populations in the 'center', and one locality record each in northern Northern Territory and northern Western Australia (Fig. 249).

Remarks. A labelling problem was encountered with the type specimens. Zwick (1977: 175) stated that the lectotype was a male from Reedy Creek; however, I found that this specimen had a paralectotype label. The specimen bearing the lectotype label was a previously undissected female which had a "Paisl Bl" [= Paisley Bluff] locality label; this specimen is designated a paralectotype in Zwick (1977). Since there is only one male with the Reedy Creek locality label, this must be the lectotype. I have therefore switched the labels, placing the lectotype label with the male, and the paralectotype label with the female. I have consulted with Ken Walker, curator at the MVMA, who concurs with the label changes.

Material Examined (172): Northern Territory, Baramundi Creek, Kakadu N. P., 12° 49' S, 132° 51' E, 18 March 1998, C. Watts (1 SAMA) ; Ellery Creek , 23° 50' S, 132° 58' E, 1–30 July 1897, unknown (paralectotype) (1 MVMA) ; Ellery Creek, Big Hole , 23° 50' S, 132° 58' E, 16 March 1998, C. H. S. Watts (29 SAMA) ; Ormiston Gorge , 23° 37' S, 132° 43' E, 16 March 1998, C. Watts (37 SAMA) ; Paisl [ey] Bl [uff] , Central Australia, coll. Horn Exped., 23° 42' S, 133° 20' E, 1–30 July 1897, unknown (paralectotype) (2 MVMA) ; Serpentine Gorge , West Macdonnells N. P., permanent rocky pools, sandy bottom, overhanging and floating vegetation, 23° 44' S, 132° 59' E, 8 March 1995, T. Weir (1 ANIC) ; Standley Chasm , 23° 43' S, 133° 27' E, 1– 30 April 1968, C. Watts (9 SAMA) ; same locality, 23° 43' S, 133° 27' E, 25 July 1969, D. D. Giuliani (7 WAMP) ; Queensland, 15 km E Mareeba , flight intercept trap, 16° 56' S, 145° 32' E, 6 February 1989, H. & A. Howden (2 CMNO) ; 40 Mile Scrub N. P. via Mt. Garnet, MDPI intercept trap site No. 13, flight intercept trap, 17° 40' S, 145° 7' E, 3–23 October 1985, Storey & Heiner (1 QPIM) ; same locality, 17° 40' S, 145° 7' E, 28 November–21 December 1985, Storey & Heiner (2 QPIM) ; 6 km SE Mareeba , MDPI F. I. T. site 36, flight intercept trap, 16° 58' S, 145° 25' E, 19 April–17 May 1991, S. De Faveri (1 QPIM) ; 9 km S Lakeland , 15° 53' S, 144° 47' E, 16 April 1980, G. F. Hevel, J. A. Fortin (5 USNM) ; Boggy Ck., 75 km Cooktown, Cooktown Rd. , 16° 37' S, 145° 21' E, 26 April 1976, E. B. Britton (8 ANIC) ; Burdekin R., 19° 41' S, 147° 36' E, 1 November 1995, C. Watts (1 SAMA) ; Burnett River, Mt. Perry Rd. , 25° 23' S, 151° 46' E, 15 August 2004, A. Glaister (1 NMW) ; Edungalba , flight intercept trap, 23° 43' S, 149° 50' E, 1 January 1987, H. & A. Howden (6 ANIC) ; Gladstone [no date], 23° 52' S, 151° 16' E ,, Lea (1 SAMA) ; Greenvale , 10 km E, 18° 57' S, 144° 50' E, 2 November 1995, C. Watts (13 SAMA) ; Magnetic Island [no date], 19° 8' S, 146° 50' E ,, A. M. Lea (3 SAMA) ; Pinnarendi Stn. , 60 km W of Mt. Garnet, at light, 17° 40' S, 145° 7' E, 7 February 1989, D. Meiiner (1 QPIM) ; Reedy St., George R. Cooktown Rd. , 16° 28' S, 144° 46' E, 22 May 1976, E. B. Britton (1 ANIC) ; Reid R. E of Charters Towers, 19° 45' S, 146° 48' E, 4 May 1998, C. H. S. Watts (26 SAMA) ; Reid R. E of Mingela, 19° 45' S, 146° 48' E, 4 May 1998, C. H. S. Watts (5 SAMA) ; Rocky Creek, Kennedy Hwy. , 17° 11' S, 145° 27' E, 27 May 1976, E. B. Britton (1 ANIC) ; Southedge Research Station , 12 km NW Mareeba, flight intercept trap, 16° 55' S, 145° 15' E, 23 January 1989 (2 CMNO) ; Windsor Tablelands , roadside pond, 16° 13' S, 145° 2' E, 7 February 1991, D. Larson (1 MCZ) ; Western Australia, Behn River, East Kimberley [no date], 16° 23' S, 128° 51' E, Helms, Griffith (3 SAMA) .

Figures

FIGURES 29–32. Hydraena, dorsal and lateral habitus of types. —29. H. simplicicollis, lectotype male. —30. H. simplicicollis, paralectotype female. —31. H. brittoni, holotype. —32. H. converga, holotype.

FIGURES 33–36. Hydraena, aedeagi of types. —33. H. simplicicollis, lectotype. —34. H. simplicicollis, lectotype (after Zwick 1977). —35. H. brittoni, holotype. —36. H. brittoni, holotype (after Zwick 1977).