Austronecta bartzarum Tinerella, 2013

Tinerella, Paul P., 2013, <strong> Taxonomic revision and systematics of continental Australian pygmy water boatmen (Hemiptera: Heteroptera: Corixoidea: Micronectidae) </ strong>, Zootaxa 3623 (1), pp. 1-121 : 19-21

Austronecta bartzarum Tinerella , sp. nov.

( Figs. 8–11 )

Diagnosis: Distinguished by the small size, unique hemelytral patterning ( Figs. 8a–b ), and diagnostic male genitalia ( Figs. 10a–g ), notably the extremely short shaft and broad base of the left paramere ( Figs. 10a–e ).

Size: ( Table 4). Brachypterous form: 2.14–2.28. Macropterous form: 2.47.

Derivation of specific epithet: This species is named honoring Gloria and Eugene Bartz, for their generous support of this research.

Notes on type material: Holotype (♂): AUSTRALIA: Western Australia: GPS Millstream, Chichester National Park, Pool in Narrina Creek. 21.21S; 117.18E. 30-IV-2003. T. Weir [ ANIC] ; Paratypes: AUSTRALIA: Western Australia: GPS Millstream, Chichester National Park, Pool in Narrina Creek. 21.21S; 117.18E. 30-IV- 2003. T. Weir. (2♂, 1♀). [ ANIC] ; Northern Territory: 97 km N of Barrow Creek. 7-IV-1966. UV Light. N. McFarland. (1♂). [ SAMA] ; Northern Territory: Stevens Creek . 12 37 86S; 130 43 26E. 14-VI-1996. (4♂, 2♀♀). [ ANIC] ; Northern Territory: Daly River, at Donsvale Crossing. 14 21 88S; 131 33 36E. 24-VI-1996. (5♂, 5♀♀). [ ANIC] ; Northern Territory: Policemans Waterhole. 15 44 39S; 129 04 34E. 18-VII-1996. (3♂, 3♀♀). [ WAMP] ; Northern Territory: Victoria River. 16 19 86S; 131 06 81E. 21-VII-1996. (1♂). [ ANIC] ; Northern Territory: Robinson River . 16 45 45S; 136 59 14E. 22-VIII-1996. (1♂). [ ANIC] ; Northern Territory: Kakadu N. P., South Magela Arm. 12.80936S; 132.996139E. 15-XII-2003. (1♂, 2♀♀). [ AMSA] ; Northern Territory: Bennett Creek , DW53. 12.6139316S; 131.0230312E. 20-IV-2004. (7♂, 3♀♀). [ USNM] ; Northern Territory: Peel Creek , DW37. 12.82214 S; 130.9087257E. 28-IV-2004. (1♂, 1♀). [ JTPC] ; Northern Territory: Stevens Creek . 12 37 86S; 130 43 26E. 14-VI-1996. (4♂, 2♀♀). [ PPTC] ; Northern Territory: Keep River, Keep River Site 13. 15.36918S; 129.08514E. 25-VII-2004. (2♀♀). [ MVMA] ; Northern Territory: Sandy River, Keep River Site 2. 15.40643S; 129.19411E. 26-VII-2004. (1♂). [ MVMA] ; Northern Territory: Sandy Creek, Keep River Site 5. 15.392S; 129.19476E. 27-VII-2004. (2♀♀). [ ACCV] ; Western Australia: Mitchell Plateau, Stop 7. 9-V-1983. Light. D. Rentz. (2♂). [ ANIC] ; Western Australia: PSW 001, Coondiner Pool, Pilbara. 15-VIII-2003. J. M. McRae. (3♂). [ PPTC] ; Western Australia: PSW 006, Fortescue Falls, Pilbara. 19-VIII-2003. J. M. McRae. (9♂, 6♀♀). [ PPTC] ; Western Australia: PSW 016, Nyeebury Spring, Pilbara. 29-VIII-2003. J. M. McRae. (6♂, 2♀♀). [ PPTC] .

Description: Based on brachypterous form. One macropterous female examined and noted below as [macropterous]. Measurements. Length: male 2.14–2.21; female 2.19–2.28 [2.47]; Width: male 1.06–1.13; female 1.04–1.09; Width of head: male 0.75–0.79; female 0.74–0.81; Synthlipsis: male 0.19–0.26; female 0.23–0.26; Width of eye: male 0.22–0.28; female 0.25–0.29; Width of pronotum: male 0.74–0.81; female 0.75–0.80; Length of pronotum: male 0.17–0.21; female 0.17–0.21 [0.28].

Color: Ground color light brown ( Figs. 8a–b ). Head same color, eyes dark reddish- brown. Vertex light brown with confined infuscated area dorsally, with three short, evenly spaced lines in medial portion. Frons and clypeus pale, same color as head, labium with dark areas restricted to apical portion. Clypeogenal area same color as frons, with sparse, small punctations. Third antennal segment with apico-medial portion embrowned. Pronotum light brown, slightly darker than general head color, darker brown at outer margins. Hemelytra: clavus and corium nearly unicolorous, lateral margins of corium darkened in basal half. Clavus with pale diagonal area basally; medial portion of each clavi with a longitudinal, evenly spaced row of circular dots numbering 10–12. Fine, reticulate microsculpturing present over clavus and corium. Membrane not developed in both wing morphs. Scutellum short, darker brown. Prenodal embolar area long, of even width to nodal suture. Nodal furrow present as near perpendicular line, almost contacting wing margin. Postnodal embolar area short, of even width to terminus. Two to three restricted, discontinuous infuscated areas along each embolium ( Figs. 8a–b ), the basal infuscation generally in second one-third of prenodal area, the apical infuscation at terminus of postnodal area. Venter pale yellow, apical and basal portions of mesofemora, meso- and metatibia with dark ring. Natatorial setae and claw of metatarsus darkened.

Structural charactersitics: Ratio of body length/width: males 1.98; females 2.14. Head nearly equal in width to pronotum, interocular space slightly narrower than width of eye, synthlipsis narrower than width of eye. Ocular index: males 0.87; females 0.91. General facies of head (vertex, frons, and labium) very short. Antennae densely pilose, segments one and two very short, third segment long, elongated, upper margin nearly straight, lower margin broadly rounded. Apex narrowly rounded. Pronotum very short in brachypters, anterior margin triangular with produced carina. Posterior margin truncate, medial portion widest with lateral margins very narrow, tapering and rounded. In brachypters, pronotum averaging four times as wide as long (W/L: males 0.78/0.19; females 0.77/0.20) in brachypters and three times as wide as long (female: 0.78/0.28) in the examined macropter. Prothoracic lobe narrow and long, with lower and posterior margins broadly rounded ( Fig. 9a ). Hemelytra with fine, reticulate microscupturing throughout, short setae densely distributed over clavus and corium. Metathoracic wings very short in brachypters, reaching only to abdominal segment V; wings of the single examined macropterous female were fully developed, reaching to apex of hemelytra. Lateral spines on abdominal segments IV-VIII: IV: one stout, short spine, one long, stout spine, one long, thin seta; V: two stout, short setae, two long, stout setae; VI: two short, stout spines, one long, stout spine; VII: two short, stout spines, two long, stout spines, one short, thin seta; VIII: five stout, short spines, one long, stout spine, one long, thin seta. Metaxyphus of both sexes very short, lateral margins rounded, apex produced and broadly rounded ( Fig. 9b ).

Male foreleg ( Fig. 9c ): femur with two short, stout spines in basal third near ventral surface, two large setae and two smaller in apical third towards dorsal surface. Tibia with three to four setae dorsally. Pala with three long setae dorsally; palmar area with 11–13 setae in upper row, 11–13 setae in lower row, ventral row setae robust, more pronounced, than dorsal row. Apex of pala with a long, thickened seta. Palar claw ( Fig. 9d ) narrow, strap-like, sides more or less parallel. Female foreleg with same general setal arrangement as male. Mesotarsal claws short, about one-fourth the length of mesotarsus.

Lateral lobes of abdominal tergum IV comparatively short and truncate. Right lobe longer, with 12 setae, left lobe shorter, with four to six long evenly spaced apically placed setae. Prestrigilar flap of tergal segment V as in Figure 9e . Strigil small, ovate, with combs densely packed. Median lobe of sternite VII ( Fig. 9f ) short, broad, with six longer setae restricted sub-basally, apex acutely pointed. Free lobe of tergite VIII ( Fig. 9g ) broad, outer lobe broadly rounded with three to four setae placed in upper portion of angle. Basal portion of lobe narrowed. Inner angle well-produced, with 19–23 long setae. Pars stridens processus cleaner ridges of tergite VIII not examined. Male left paramere ( Figs. 10a–f ) very short, base exceptionally broad, rounded ( Figs. 10a–b, d, e ). Tip of left paramere acute, rounded ( Fig. 10c ). Right paramere ( Figs. 10a–b, d, e ) with convexly curved shaft, nearly parallelsided, tip of paramere slightly expanded, and rounded ( Fig. 10f ). Base of right paramere long, with outer lobe angulate. Pars stridens processus restricted to medial portion of base, plectral ribs wide, numbering about 28 ( Fig. 10g ). Aedeagus broad, as in Figures 10a–b, d–f .

Distribution and Habitat: ( Fig. 11 ). AUSTRALIA: Northern Territory, Western Australia. This species was collected mostly from rivers, with some collections from small, stagnant pools. The single examined macropterous specimen was taken at UV light.

Discussion: A distinct, fairly common species, at least locally, throughout tropical Northern Territory and the Pilbara region of Western Australia.

This species is placed in Austronecta on the basis of the triangulate hind margin of the head, well-developed anterior pronotal carina, and the absence of scales in the distal portion of the male left paramere. Further, the general habitus and tergal morphology are distinct and similar to other Austronecta species. The species is easily distinguished by the unique hemelytral patterning and the distinct, shortened left paramere. Austronecta bartzarum is likely to be confused only with A. micra , on the basis of size, general body form, and varying reddish-brown ground color. Austronecta micra , however, lacks the unique hemelytral patterning seen in A. bartzarum .

Figures

FIGURE 8. Austronecta bartzarum, sp. nov. a. Male. b. Female. Scale bars = 0.5 mm.

FIGURE 9. Austronecta bartzarum sp. nov. a. Prothoracic lobe, female. b. Metaxyphus. c. Left male foreleg, posterior aspect. d. Left male pala (tarsus), anterior aspect, palar claw everted. e. Prestrigilar flap of abdominal segment V. f. Sternal process of abdominal segment VII. g. Free lobe of abdominal tergum VIII. Scale bars = 0.1 mm.

FIGURE 10. Austronecta bartzarum sp. nov., male genitalia. a. Left paramere, lateral aspect, right paramere, dorso-medial aspect. b. Left paramere, lateral aspect (cf base Fig. a), right paramere, dorso-medial aspect. c. Left paramere, tip. d. Left paramere, base, right paramere, fronto-lateral aspect. e. Left paramere, base, right paramere, lateral aspect. f. Right paramere, tip. g. Pars stridens processus, base of right paramere.

FIGURE 11. Distribution of Austronecta bartzarum sp. nov.