Micronecta Kirkaldy

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 : 31-33

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-160A-9C56-FF46-FF234DD16C0E
treatment provided by	Felipe
scientific name	Micronecta Kirkaldy
status

Treatment

Micronecta Kirkaldy View in CoL

( Figs. 16–64 View FIGURE 16 View FIGURE 17 View FIGURE 18 View FIGURE 19 View FIGURE 20 View FIGURE 21 View FIGURE 22 View FIGURE 23 View FIGURE 24 View FIGURE 25 View FIGURE 26 View FIGURE 27 View FIGURE 28 View FIGURE 29 View FIGURE 30 View FIGURE 31 View FIGURE 32 View FIGURE 33 View FIGURE 34 View FIGURE 35 View FIGURE 36 View FIGURE 37 View FIGURE 38 View FIGURE 39 View FIGURE 40 View FIGURE 41 View FIGURE 42 View FIGURE 43 View FIGURE 44 View FIGURE 45 View FIGURE 46 View FIGURE 47 View FIGURE 48 View FIGURE 49 View FIGURE 50 View FIGURE 51 View FIGURE 52 View FIGURE 53 View FIGURE 54 View FIGURE 55 View FIGURE 56 View FIGURE 57 View FIGURE 58 View FIGURE 59 View FIGURE 60 View FIGURE 61 View FIGURE 62 View FIGURE 63 View FIGURE 64 )

Micronecta Kirkaldy, 1897a: 260 View in CoL . (= Sigara sensu Leach, 1817: 14 View in CoL , not Fabricius 1775 ( Puton 1899)). Distant, 1906: 50; Hale, 1922: 323; Hutchinson, 1929: 422; Jaczewski, 1937: 584, 586, 589; Hutchinson, 1940: 347; China, 1943: 283; Poisson, 1951: 1753; Villiers, 1952: 208; Usinger, 1963: 191; Chen, 1965: 147; Wróblewski, 1970: 681; Popov, 1971: 134; Wróblewski, 1972b: 517; Linnavuori, 1981: 2–4; Jansson, 1986: 8–19; Kanyukova, 1990: 13; Jansson, 1995: 27; Cassis and Gross, 1995: 66; Nieser, 1999a: 9, 1999b: 277; Nieser and Chen, 1999: 78; Chen et al., 2002: 195; Nieser, 2002a: 9, 2002b: 264; Nieser et al., 2004: 30; Andersen and Weir, 2004: 246; Tinerella and Polhemus, 2005: 183; Chen et al., 2005: 144; Tinerella, 2006b: 141; Tinerella, 2008: 27 View Cited Treatment .

Type species: By original designation, Notonecta minutissima Linnaeus, 1758 .

Description: Small (0.8–5.5 mm), generally ovate to sub-parallel sided micronectids. Ground color brown to black often with darker longitudinal, reticulate, or mottled patterning. Vertex of head rounded to conically produced, foveate depression absent. Head sclerites broader, frons and clypeus proportionate surrounding the short labium (unsegmented rostrum). Labial apex exceeding a line drawn through apical genal margins, head thus appearing longer in general outline. Prothoracic lobe robust, often wider than long, subquadrate to rectangular. Metaxyphus longer, reaching beyond basal portion of hind coxae, triangular, and often with acute apex.

Pronotum robust in macropters, well-developed, convex and broadest medially. In brachypterous forms, the pronotum is proportionately reduced, often much shorter than exemplars with fully developed flight muscles. Anterior pronotal carina weakly developed to absent. Hemelytra uniformly clothed with numerous short spines, microsculpturing variable though always present. Nodal furrow entire, marked by well-developed perpendicular suture which reaches outer margin of wing. Prenodal embolar area well-developed, post-nodal embolar area shorter, though pronounced. Palae generally robust, palar claw of males widened, often expanded, apex rounded. Profemur with two or four setae basally, near ventral margin. Tergal lobes of abdominal segment IV welldeveloped, long and broadly rounded apically. Strigil present, of variable sizes, though always conspicuous. Strigil absent in Micronecta (Micronectella) acuta Lundblad and M. (Indonectella) grisea Fieber. Sternal process of abdominal segment VII long, apex broadly acuminate or rounded. Free lobe of abdominal tergite VIII with outer angle rounded and inner angle at least partly rounded. Male parameres: left paramere with apical modification or not, scales present in distal third in all Australian species. Right paramere with rectangular base, shaft length variable, apex often expanded. Tip rounded or pointed. Pars stridens processus generally spanning entire width of paramere base; pars stridens processus distributed over at least medio-apical portion and often expanded to basal portion.

Discussion: The current generic-level classification of Micronecta was discussed in detail by Tinerella (2006a, 2006b, 2008). Within Micronecta , the present subgeneric classification consists of ten marginally defined subgenera and numerous unplaced taxa. Complete examination and redescription of the genotype M. minutissima Linnaeus is needed to fix the generic concept. The generic definition given above for Micronecta is based on examination of exemplars of M. minutissima , most subgenotypes representing the current subgeneric classification, and analysis and redescription of Australasian Micronecta (see also Tinerella 2006b, 2008). This definition will undoubtedly be narrowed as other regional faunae are examined and generic limits revised.

Australian Micronecta are currently comprised of two primary elements. The ‘ M. annae ’ species group ( Tinerella 2006b, 2008) consists of 13 species ( Table 6). Nine species are restricted to continental Australia, two species share distributions with New Guinea, one species, M. carbonaria , is endemic to New Guinea, and the last species, M. jenniferae Tinerella , is presently only known from Fiji. Micronecta paragoga sp. nov., is herein placed within the M. annae species group, based on the shared male genitalic characters (viz. apical scales of the male left paramere) and similar abdominal morphology (lateral lobes of abdominal segment IV and shape of the free lobe of abdominal tergite VIII) shared with other species of the annae group. The species of the annae group occurring in New Guinea and Oceania were recently revised by Tinerella (2008).

Two widespread species form the second element of the Australian Micronecta fauna: M. ludibunda and M. quadristrigata Breddin. Both species are distributed throughout Australasia and are known westward from India ( M. ludibunda ) and Iran ( M. quadristrigata ). Micronecta ludibunda is newly reported here for Australia, based on one macropterous male specimen examined from Queensland. The systematic position of these two species within Micronecta is unclear and was discussed by Tinerella (2006b, 2008). Additional discussion is provided below.

Key to the Species of Micronecta Kirkaldy View in CoL of Australia

1. Small, generally ovate species, length 1.79–2.36 mm; pronotum short, narrow to broadly triangular; ground color brown, hemelytral patterning with or without longitudinal stripes ( Figs. 16a–b View FIGURE 16 , 20a–b View FIGURE 20 ); metaxyphus short, apex produced as a rounded lobe ( Figs. 17b View FIGURE 17 , 21b View FIGURE 21 )................................................................................... 2

– Larger species, length> 2.51 mm; pronotum generally well-developed and proportionate with head; ground color light brown with hemelytral patterning developed as longitudinal stripes or effaced; metaxyphus long and triangular, apex not produced....... 3

2(1). Small, ovate species, length of brachypter 1.79–1.93 mm, macropterous form slightly larger, length 2.28–2.32 mm; interocular space wider than width of eye ( Figs. 16a–b View FIGURE 16 ); pronotum short, embracing broadly rounded margin of head ( Figs. 16a–b View FIGURE 16 ); hemelytral patterning mottled medio-apically, with expanded diagonal lightened corial area ( Figs. 16a–b View FIGURE 16 ); metaxyphus ( Fig. 17b View FIGURE 17 ); male parameres ( Figs. 18a–e View FIGURE 18 )................................................... M. paragoga View in CoL sp. nov. (pg. ####)

– Small, elongate species, length of brachypter 1.86–2.23 mm, length of macropter 2.14–2.36 mm; interocular space narrower than width of eye ( Figs. 20a–b View FIGURE 20 ); pronotum longer, triangular, and often with dark transverse medial band ( Figs. 20a–b View FIGURE 20 ); ground color brown, hemelytral patterning consisting of longitudinal dark stripes ( Figs. 20a–b View FIGURE 20 ); metaxyphus ( Fig. 21b View FIGURE 21 ); male parameres ( Figs. 22a–f View FIGURE 22 )....................................................... M. ludibunda Breddin View in CoL (pg. ####)

3(1). Pronotum and head proportionately very short ( Figs. 23a–d View FIGURE 23 ); hemelytral patterning effaced or with four weakly developed longitudinal stripes ( Figs. 23a–d View FIGURE 23 ); hind tibia armed with numerous long, stout spines; male parameres ( Figs. 25a–g View FIGURE 25 ); length 2.82–3.28 mm ............................................................ M. lansburyi Wróblewski View in CoL (pg. ####)

– Pronotum and head proportionately longer; hemelytral patterning variable; hind tibia with regular series of spines; length variable................................................................................................ 4

4(3). Pronotum exceptionally large, longer than head ( Figs. 27a–b View FIGURE 27 ); hemelytral patterning consisting of two or three discontinuous longitudinal stripes, embolium with dark discontinuous areas ( Figs. 27a–b View FIGURE 27 ); male left paramere with apical scales highly reduced ( Figs. 29a–d View FIGURE 29 )........................................................... M. adelaidae Chen View in CoL (pg. ####)

– Pronotum and head length generally equal; hemelytral patterning variable; male left paramere with apical scales.......... 5

5(4). Larger species,> 3.5 mm ................................................................................ 6

– Smaller species, <3.5 mm ............................................................................... 7

6(5). Length 4.15–4.54 mm; vertex of both sexes conically produced ( Figs. 31a–b View FIGURE 31 ); ground color dark brown, corium with two or three short dark longitudinal lines ( Figs. 31a–b View FIGURE 31 ); male left paramere ( Figs. 33a–f View FIGURE 33 ), right paramere abruptly expanded distally ( Figs. 33a–f View FIGURE 33 )..................................................................... M. major Chen View in CoL (pg. ####)

– Length 3.52–4.09 mm; vertex of both sexes rounded, at most only slightly produced ( Figs. 35c–e View FIGURE 35 ); hemelytral patterning faint, corium with four long, dark longitudinal stripes ( Figs. 35c–e View FIGURE 35 ); male left paramere ( Figs. 37d–g View FIGURE 37 ); right paramere broadly expanded apically ( Figs. 37d–g View FIGURE 37 )..................................................... M. robusta Hale View in CoL (pg. ####)

7(5). Vertex in both sexes conically produced.................................................................... 8

– Vertex in both sexes rounded............................................................................ 9

8(7). Ground color sandy-brown, hemelytral patterning entirely effaced ( Figs. 38a–b View FIGURE 38 ); pronotum unicolorous ( Figs. 38a–b View FIGURE 38 ); male left paramere ( Figs. 40a–c View FIGURE 40 ), right paramere evenly expanded apically ( Figs. 40d–e View FIGURE 40 ); length 3.13–3.71 mm ....................................................................................... M. tasmanica Wróblewski View in CoL (pg. ####)

– Ground color light brown, hemelytral markings variable, unicolorous dark, to markings present as dark longitudinal lines ( Figs. 41c–e View FIGURE 41 , 42a–b View FIGURE 42 , 43a–d View FIGURE 43 ); pronotum often with dark transverse bar ( Figs. 41c–e View FIGURE 41 ); left paramere convexly curved, with sharp apical hook ( Figs. 45d–f View FIGURE 45 ), right paramere parallel-sided, pointed apically ( Figs. 45d–g View FIGURE 45 ); brachypter length 2.74–3.44 mm, macropter length 3.18–3.62 mm ................................................... M. annae Kirkaldy View in CoL (pg. ####)

9(7). Slender, elongate species ( Figs. 46c–e View FIGURE 46 ), length 2.75–3.82 mm; hemelytral markings present as interrupted longitudinal streaks ( Figs. 46c–e View FIGURE 46 ); male palar claw broadly expanded ( Figs. 47d View FIGURE 47 , 48a View FIGURE 48 ); left paramere long and slender, with sharp apical hook ( Figs. 48b–f View FIGURE 48 )......................................................................... M. gracilis Hale View in CoL (pg. ####)

– Wider, evenly proportionate species; hemelytral markings weakly developed or present as distinct longitudinal stripes; male palar claw narrow; left paramere not modified as above...................................................... 10

10(9). Hemelytra with four distinct, dark longitudinal stripes ( Figs. 49c–e View FIGURE 49 ); larger species, 2.89–3.50 mm; left male paramere ( Figs. 51c–f View FIGURE 51 ); right male paramere long, tip expanded and broadly rounded ( Figs. 51c–g View FIGURE 51 ); Australia, Papua New Guinea, Solomon Islands.......................................... ………………………………………… M. virgata Hale View in CoL (pg. ####)

– Hemelytral patterning weakly developed as discontinuous longitudinal markings length 2.51–3.34 mm ................. 11

11(10). Hemelytral patterning ill-developed, at most a faint longitudinal series in medial portion of corium ( Figs. 53b–d View FIGURE 53 ); length 2.77–3.34 mm; palar claw expanded apically ( Fig. 54d View FIGURE 54 ); sternal process of abdominal segment VII short, apex acute ( Fig. 54f View FIGURE 54 ); left male paramere ( Figs. 55a–d View FIGURE 55 )....................................................... M. halei Chen View in CoL (pg. ####)

– Hemelytral patterning forming a faint series of three or four discontinuous longitudinal bands…....................... 12

12(11). Length 2.51–2.90 mm; hemelytra with dark markings present as interrupted longitudinal series forming four broken bands ( Figs. 57a–b View FIGURE 57 ); palar claw parallel-sided, rounded apically ( Fig. 59a View FIGURE 59 ); sternal process of abdominal segment VII long, apex finger-like ( Fig. 58e View FIGURE 58 ); left male paramere with pronounced hook-shaped apex ( Figs. 59c–d View FIGURE 59 ); right paramere long, slender ( Figs. 59c–g View FIGURE 59 ); widespread, Iran to Oceania.......................................... M. quadristrigata Breddin View in CoL (pg. ####)

– Length 2.6–3.0 mm; hemelytra with lighter markings forming three discontinuous longitudinal stripes ( Figs. 61a–b View FIGURE 61 ); palar claw narrow ( Fig. 62d View FIGURE 62 ); sternal process of abdominal segment VII short, apex blunt ( Fig. 62f View FIGURE 62 ); left male paramere with triangular apex ( Figs. 63a–c View FIGURE 63 ); right male paramere broad ( Figs. 63a–c View FIGURE 63 ); Papua New Guinea, northern Australia........................................................................................... M. queenslandica Chen View in CoL (pg. ####)