Micronecta carbonaria Horváth, 1904

Tinerella, Paul P., 2008, Taxonomic revision and systematics of New Guinea and Oceania pygmy water boatmen (Hemiptera: Heteroptera: Corixoidea: Micronectidae), Zootaxa 1797 (1), pp. 1-66 : 49-53

Micronecta carbonaria Horváth, 1904

( Figs. 16i–j , 29–31 )

Micronecta carbonaria Horváth, 1904: 595 .

Micronecta carbonaria: Lundblad, 1933: 76 . [list]

Micronecta carbonaria: Wróblewski, 1962b: 319 . [Lectotype designation, redescription]

Micronecta carbonaria: Chen, 1965: 163 . [faunistics]

Micronecta carbonaria: Tinerella and Polhemus, 2005 : [key; faunistics]

Micronecta carbonaria: Chen et al., 2005: 420 . [list]

Micronecta carbonaria: Tinerella, 2006a . [phylogenetic relationships]

Diagnosis: This species is easily distinguished by its dark (usually black) ground color ( Figs. 16i–j ), wide interocular space, and male parameres ( Figs. 30b–f ). It is similar in size to M. virgata Hale , but lacks the longitudinal hemelytral stripes of the former species. It is restricted to New Guinea.

Size: ( Table 11). Macropterous form: 3.0–3.44. The recorded metrics expand the previously recorded size (length) of the species. Brachypterous form unknown.

Derivation of specific epithet: From the Latin carbo, meaning charcoal; referring apparently to the typical dark ground color of this species.

Notes on type material: Wróblewski (1962b) designated a lectotype from Horváth’s type series in HNHM. I was unable to verify or obtain any type material from HNHM

Description: Based on macropterous form. Measurements. Length: male 3.0–3.24; female 3.26–3.44; Width: male 1.61–1.71; female 1.72–1.91; Width of head: male 1.27–1.35; female 1.28–1.41; Synthlipsis: male 0.58–0.63; female 0.61–0.69; Width of eye: male 0.31–0.45; female 0.35–0.47; Width of pronotum: male 1.21–1.31; female 1.24–1.33; Length of pronotum: male 0.33–0.44; female 0.32–0.42.

Color. Ground color black to dark reddish black ( Figs. 16i–j ). Head paler brown, eyes silver to slate-grey. Vertex infuscated, apicomedial portion of frons pale, clypeus and labium dark brown. Clypeogenal area darker, densely, uniformly punctate. Antennae pale. Pronotum, clavus, corium, membrane uniformly dark throughout, with reticulated microsculpturing. Scutellum with basal portion pruinose. Prenodal embolar area with basal ½ pruinose. Left membrane in both sexes hyaline, pale white, right membrane coriaceous, brown. Venter dark, infuscated. Legs dark brown to black, apical and basal portions lighter in color.

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

Structural characteristics. Ratio of body length/width: males 1.86; females 1.86. Head slightly wider than pronotum, interocular space greater than width of eye, synthlipsis 1.6 times as wide as posterior width of eye. Ocular index: males 1.71, females 1.78. General facies of head (vertex, frons, labium) evenly proportionate. Antennae densely pilose, segments one and two very short, third segment long, elongated, elliptical in outline, apex sharply pointed. Prothoracic lobe broad, anterior margin acuminate, posterior margin rounded ( Fig. 29a ). Pronotum robust, convexly rounded, widest at middle portion, lateral margins tapering, nearly five times as wide as long (W/L: males 1.68/0.37; females 1.80/0.39). Hemelytra with fine, wavy microsculpture, short setae distributed evenly throughout. Nodal furrow distinct, marked by nearly perpendicular suture. Prenodal embolar area long, widened basally. Post-nodal embolar area shorter, widened in anterior portion, tapering abruptly. Metathoracic wings fully developed, reaching nearly to apex of hemelytra. Lateral spines and setae on abdominal segments IV–VIII: IV: one stout, short spine, two long, thin; V: three stout, short spines, two long; VI: four stout short spines, one long; VII: three short, stout spines, two long; VIII: four stout spines of varying lengths and five long, thin spines. Metaxyphus of both sexes short, triangular, with evenly distributed short setae, apex acute ( Fig. 29b ).

Male foreleg ( Fig. 29c ): femur with two short, stout spines on basal third near ventral surface, one large seta on apical third towards dorsal surface, three stout setae apically. Tibia with one small mediodorsal seta on apical third, two stout setae apically. Pala with six long setae dorsally; palmar area with 10–11 setae in upper row, 11–12 setae in lower row; ventral row setae more pronounced than dorsal row. Apex of pala with single thickened seta. Palar claw ( Fig. 29d ) elongate, rounded, with shortened apical curve. Female foreleg with same general setal arrangement as male. Mesotarsal claws short, about one-third the length of mesotarsus.

Lateral lobes of abdominal tergum IV broadly rounded, each lobe with 12–13 long evenly spaced apical setae. Prestrigilar flap of abdominal tergum V as in Figure 29e . Strigil narrowed, elongate, with numerous densely packed combs. Median lobe of abdominal sternum VII ( Fig. 29f ) long, rounded apically; setae restricted basally, with five longer setae arranged in semicircular row spanning width of lobe. Free lobe of abdominal tergite VIII ( Fig. 30a ) broad, rounded, with outer angle setae short and restricted lateral margin; inner angle with 24–26 setae. Pars stridens processus cleaner ridges of abdominal segment VIII appearing as a fine-ridged mat. Left paramere shorter ( Figs. 30b–e ), shaft parallel-sided, widened medially, apical portion curved with tip rounded ( Figs. 30b–c ). Paramere base broad ( Figs. 30b, d ). Right paramere ( Figs. 30b–e ) with long curved shaft, basal third constricted ( Figs. 30b–e ); tip of paramere expanded, triangular ( Figs. 30d–e ). Base of right paramere subquadrate, pars stridens processus consisting of about 38 plectral ribs spanning width ( Fig. 30f ). Aedeagus broad, as in Figures 30b–e .

Distribution and habitat: ( Fig. 31 ). Indonesian New Guinea and Papua New Guinea; at present known only from the northern portion of the island. There are no specific habitat data. Most specimens examined in this writing and from the literature have been collected at lights.

Discussion: Micronecta carbonaria is clearly allied with M. virgata and other species of the annae species group. In his redescription, Wróblewski (1962b) noted examining only brachypters, with “wings developed to tip of 8 th tergum”. All specimens examined during this work have well developed hind wings, reaching to abdominal segment VIII or beyond; and most were collected at lights, indicating that the species flies.

In New Guinea and Oceania, Micronecta carbonaria , along with M. virgata and M. jenniferae form a closely related group of species with clear relationships to continental Australian species. The species is undoubtedly an offshoot of the annae species group, becoming established and isolated on the northern portion of the island.

Specimens Examined: INDONESIA: Irian Jaya Prov. [= Papua Prov.]: Neth. Hollandia Area, W. Sentani, Cyclops Mts. , 200–1000 m. (16–18)- VI-1959. J. L. Gressitt. (1♂, 1♀). [ BPBM] ; Irian Jaya Prov. [= Papua Prov.]: Neth. Hollandia Area, W. Sentani, Cyclops Mts. , 50– 100 m. (22–24)- VI-1959. Light Trap. J. L. Gressitt & T . C. Maa. (3♂♂, 3♀♀). [ BPBM] ; Irian Jaya Prov. [= Papua Prov.]: Hol Maffen , 22 km E of Sarmi. (18– 19)- VII-1959. T . C. Maa. (1♀). [ BPBM] ; Irian Jaya Prov. [= Papua Prov.]: Neth. Sarmi, W to Hollandia. (20– 23)- VII-1959. T . C. Maa. (1♀). [ BPBM] ; PAPUA NEW GUINEA: East Sepik Province: Amboin Patrol Post, Karawari Lodge. 11-I-1983. A. C. Messer. (16♂♂, 22♀♀). [ USNM]; same data. 13-I-1983. A. C. Messer. (13♂♂, 21♀♀). [ USNM]; N. New Guinea: Torricelli Mts. , 200–1000 m. I-1939. E. L. Cheesman. (2♂♂). [ SAMA]; NE: May R ., Patrol Station , 100 m. 31-V-1963. Light Trap, Bishop. R . Straatman. (1♀). [ BPBM] .

Figures

FIGURE 16. Dorsal habitus of Micronecta species. a–b. M. ludibunda Breddin, male and female. c–d. Micronecta jenniferae Tinerella, male and female. e–f. M. quadristrigata Breddin, male and female. g–h. M. queenslandica Chen, male and female. i–j. M. carbonaria Horvath, male and female. k–l. M. virgata Hale, male and female. Scale bars = 0.5 mm.

FIGURE 29. Micronecta carbonaria Horváth. a. Prothoracic lobe, female. b. Metaxyphus. c. Left male foreleg, posterior aspect. d. Left male pala (tarsus), anterior aspect, palar claw folded in. e. Prestrigilar flap of abdominal segment V. f. Sternal process of abdominal segment VII. Scale bars = 0.1 mm.

FIGURE 30. Micronecta carbonaria Horváth, male abdominal terminalia. a. Free lobe of abdominal tergite VIII. b. Left paramere, lateral aspect. c. Left paramere, tip. d. Right paramere, lateral aspect. e. Right paramere, dorsolateral aspect. f. Pars stridens processus, base of right paramere.

FIGURE 31. Distribution of Micronecta carbonaria Horváth.