Austronecta micra ( Kirkaldy, 1908 ) 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 : 14-19

publication ID	https://doi.org/ 10.11646/zootaxa.3623.1.1
publication LSID	lsid:zoobank.org:pub:7ACE38F7-7FF2-4E36-A8A2-F1323101A128
persistent identifier	https://treatment.plazi.org/id/567D87EC-1619-9C64-FF46-FD3B4D5E6D9F
treatment provided by	Felipe
scientific name	Austronecta micra ( Kirkaldy, 1908 )
status	comb. nov.

Treatment

Austronecta micra ( Kirkaldy, 1908) View in CoL , comb. nov.

( Figs. 4–7 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 )

Micronecta micra Kirkaldy, 1908: 788 View in CoL .

Micronecta micra: Hale, 1922: 328 View in CoL . [note]

Micronecta micra: Lundblad, 1933: 76 View in CoL . [list]

Micronecta micra: Chen, 1965: 148 View in CoL . [key, redescription]

Micronecta micra: Wróblewski, 1972b: 524 View in CoL . [list]

Micronecta micra: Cassis and Gross, 1995: 68 View in CoL . [catalog]

Micronecta micra: Andersen and Weir, 2004: 335 View in CoL . [list]

Diagnosis: Readily distinguished by its small size, habitus ( Figs. 4a–b View FIGURE 4 ), and distinct left male paramere ( Figs. 6a–c View FIGURE 6 ). Several specimens examined for this writing were bright red in general coloration. Confused perhaps only with A. bartzarum , but readily separated by size, coloration ( Figs. 8a–b View FIGURE 8 ), and genitalia ( Figs. 10a–f View FIGURE 10 ).

Size: ( Table 3). Brachypterous form: 1.65–1.90. Macropterous form: 1.91.

Derivation of specific epithet: From the Latin micra , referring to the very small size of this species.

Notes on type material: Kirkaldy’s type series is unknown. The material was not located in the BPBM or SEMC. Chen (1965) listed seven specimens (5♂, 2♀♀) from the type locality, all deposited in SEMC. I was unable to examine these seven specimens.

Description: Based on brachypterous form. One macropterous male examined and noted below as [macropter]; measurement data are included in Table 3. Measurements. Length: male 1.65–1.81; female 1.72–1.90; Width: male 0.79–0.98; female 0.86–0.94; Width of head: male 0.64–0.72; female 0.68–0.74; Synthlipsis: male 0.64–0.72; female 0.68–0.76; Width of eye: male 0.18–0.25; female 0.23–0.26; Width of pronotum: male 0.58–0.73 [macropter]; female 0.24–0.29; Length of pronotum: male 0.11–0.26 [macropter]; female 0.13–0.15.

Color: Ground color light reddish-brown ( Figs. 4a–b View FIGURE 4 ). Head light yellowish-brown, eyes dark reddish-brown. Vertex light yellow, with three evenly spaced red longitudinal lines running from hind margin of head to vertex. Frons and clypeus pale, labium dark brown to black. Clypeogenal area same color as frons, uniformly punctate. Antennae pale. Pronotum uniformly brown, with pale, apical band spanning width, the band discernible in most specimens examined. Hemelytra: clavus, corium, and membrane with irregular dark red mottling trending longitudinal on clavus and lateral margins of corium. Fine, densely packed, mesh-like microscupturing present throughout hemelytra. Scutellum short, unicolorous light reddish-brown. Prenodal embolar area short, widened, lacking distinct pruinosity. Nodal furrow hardly distinguishable, very short. Postnodal area widened. Two to three restricted, discontinuous infuscated areas along each embolium ( Figs. 4a–b View FIGURE 4 ). Left membrane same color as hemelytral ground color, appearing hyaline only at inner margin. Venter pale reddish-yellow, natatorial setae and claws of metatarsus black.

(M= macropterous). L= length, LP= length of pronotum, W= body width, WH= width of head, S= synthlipsis, WE= width of an eye, WP= width of pronotum, L:W= ratio body length to width, S:E= ratio of synthlipsis to eye width, OcI= ocular index.

Structural charactersitics: Ratio of body length/width: males 1.96; females 2.06. Head slightly wider than pronotum, interocular space nearly equal to width of eye, synthlipsis as wide as posterior width of eye. Ocular index: males 1.05; females 1.03. General facies of head (vertex, frons, and labium) very short. Antennae densely pilose, segments one and two very short, third segment long, elongated, ovate, with apex narrowly rounded. Pronotum very short in brachypterous form, anterior margin triangular, with sharp, well-produced carina. Posterior margin truncate, medial portion widest with lateral margins very narrow, tapering. Pronotum in brachypterous forms averaging six times as wide as long (W/L: males 0.91/0.17; females 0.89/0.14). Single examined macropterous specimen with robust, well-developed pronotum. Anterior margin triangular and posterior margin nearly straight; lateral margins acutely tapered. Macropterous pronotum 2.8 times as wide as long (W/L: 0.73/ 0.26). Prothoracic lobe narrow, lower and posterior margins broadly rounded ( Fig. 5a View FIGURE 5 ). Hemelytra with fine, densely packed, mesh-like microscupturing throughout, short setae distributed over clavus and corium. Metathoracic wings very short in brachypters, reaching only to abdominal segment IV; wings of the single examined macropterous male were fully developed, reaching to apex of hemelytra. Lateral spines on abdominal segments IV-VIII: IV: one stout, short spine, one long, thin spine; V: two stout, short setae, one long, stout seta, one long, thin seta; VI: one long, stout spine, two long, thin setae; VII: two short, stout spines, two short, thin setae; VIII: four stout, short spines, two long, thin setae. Metaxyphus of both sexes very short, broadly triangular, apex rounded ( Fig. 5b View FIGURE 5 ).

Male foreleg ( Fig. 5c View FIGURE 5 ): femur with two short, stout spines in basal third near ventral surface, two large setae in apical third towards dorsal surface. Tibia with one seta medio-dorsally, three longer setae placed apically. Pala with three long setae dorsally; palmar area with 11–13 setae in upper row, 13–14 setae in lower row; ventral row setae robust, more pronounced than dorsal row. Apex of pala with a single, short, thickened seta. Palar claw ( Fig. 5d View FIGURE 5 ) narrow, elongated, widest at medial portion. 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 narrow, truncate. Right lobe longer, with four to five long setae, left lobe shorter, with eight long evenly spaced apically placed setae. Prestrigilar flap of tergal segment V as in Figure 5e View FIGURE 5 . Strigil very long, rectangular, with numerous densely packed combs. Median lobe of sternite VII ( Fig. 5f View FIGURE 5 ) short, broad, with four longer setae restricted sub-basally, apex pointed. Free lobe of tergite VIII ( Fig. 5g View FIGURE 5 ) broad, outer lobe broadly rounded, basal portion narrowed. Inner angle with 13–18 long setae. Pars stridens processus cleaner ridges of tergite VIII not examined.

Male left paramere ( Figs. 6a–d View FIGURE 6 ) with shaft convex, curved upward, apical portion curved with broad, blunt tip ( Figs. 6a–c View FIGURE 6 ). Paramere base broad, hatchet shaped ( Figs. 6a–d View FIGURE 6 ). Right paramere ( Figs. 6d–e View FIGURE 6 ) with convexly curved shaft, nearly parallel-sided, tip of paramere expanded ( Figs. 6c–d View FIGURE 6 ). Base of right paramere rectangular, with about 24 plectral ribs restricted to medio-lateral portion ( Fig. 6e View FIGURE 6 ). Aedeagus broad, as in Figures 6a–d View FIGURE 6 .

Distribution and Habitat: ( Fig. 7 View FIGURE 7 ). AUSTRALIA: Northern Territory, Queensland, Western Australia. General habitat and collection method data are absent for the examined brachypterous specimens. The single examined macropterous specimen was taken at UV light.

Discussion: Austronecta micra is the smallest known micronectid from Australasia. The single macropterous specimen examined was similar in general habitus to the brachypter, except that the pronotum was proportionately expanded with the apical margin rounded. The species appears more common than previously realized and is well represented in recent collections throughout Northern Territory and Western Australia. In previous revisions of the Australian Micronectidae , only Chen (1965) examined specimens of A. micra . Hale (1922) repeated Kirkaldy’s (1908) description and Wróblewski (1972b) included the species in a checklist. Wróblewski’s (1970) prior comments on possible synonymy of A. micra with Micronecta ludibunda were unfounded and based solely on speculation from having not seen the species.

Based on examined recent collections, the species seems to be locally abundant throughout localities in Northern Territory and the Pilbara region of Western Australia. Further study of museum material, especially light trap collections, will likely yield more macropterous specimens.

Specimens examined: AUSTRALIA: Northern Territory: 48 km SE Adelaide River. 10-IV-1966. UV Light. N. McFarland. (1♂). [ SAMA] ; Northern Territory: Daly River . 13.45S; 130.42E. (9–10)- VIII-1980. M. B. Malipatil. (7♂, 4♀♀). [ MAGD] GoogleMaps ; Northern Territory: Limestone Gorge (operation Raleigh , 1986). 16.02S; 130.23E. (23–26)- VI-1986. M. B. Malipatil. (1♂, 1♀). [ MAGD] GoogleMaps ; Northern Territory: Bullita out station; (operation Raleigh , 1986). 16.075S; 130.25E. 22-VI-3-VII-1986. M. B. Malipatil. (2♀♀). [ MAGD] GoogleMaps ; Northern Territory: Out station; (operation Raleigh , 1986). 16.075S; 130.25E. 3-VII-1986. M. B. Malipatil. (2♂, 2♀♀). [ MAGD] GoogleMaps ; Queensland: Claudie River , 5 mi W Mt. Lamond. 24-XII-1971. McAlpine, Holloway, & Sands. (1♂, 1♀). [ AMSA] ; Western Australia: Carawine Gorge - Pilbara , PSW 024. 4-IX-2003. J. M. McRae. (20♂, 15♀♀). [ CALM] ; Western Australia: Pelican Pool - Pilbara , PSW 021. 9-IX-2003. J. M. McRae. (4♂, 3♀♀). [ CALM] ; Western Australia: Sherlock River - Pilbara , PSW 056. 11-IX-2004. J. M. McRae. (1♂, 1♀). [ CALM] .