Papuanecta minajerwi ( Tinerella and Polhemus, 2005 ) Tinerella, 2008

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 : 17-22

Papuanecta minajerwi ( Tinerella and Polhemus, 2005) , comb. nov.

( Figs. 1e–f , 8–11 )

Micronecta minajerwi Tinerella and Polhemus, 2005: 184 .

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

Diagnosis: The males of this small, distinct species are readily recognized by the tergal morphology, distinct free lobe of abdominal tergite VIII ( Figs. 9g , 10a ), and the characteristic male parameres ( Figs. 10b–f ). This species is similar in habitus to P. sinistra (Chen) , but differs on the basis of dextral abdominal asymmetry (males) and the nonstriate hemelytra (females). Females are further distinguished by the size and combination of the prothoracic lobe ( Fig. 9a ) and metaxyphus ( Fig. 9b ).

Size: ( Table 4). Brachypterous form: 1.66–1.81. Macropterous form unknown.

Derivation of specific epithet: A noun in apposition, referring to the type locality, the Minajerwi River , southwestern Indonesian New Guinea .

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.

Notes on type material: Holotype (♂): ( Figs. 8a–b ) INDONESIA: Irian Jaya Prov. [= Papua Prov]: Freeport, 2 nd stream on boardwalk trail leading east of Mile 50 (storage tank site) on Tembagapura Road , 34 km N of Timika; 4°16.99' S; 137° 00.86' E, CL-2989, 16 March 1997, Coll. J. T. Polhemus . Paratypes: same data. (1♂, 1♀) [ USNM] ; same data. (1♂). [ JTPC] ( Tinerella and Polhemus 2005) .

Description: Based on brachypterous form. Measurements. Length: male 1.66–1.81; female 1.69; Width: male 0.84–0.89; female 0.81; Width of head: male 0.61–0.64; female 0.63; Synthlipsis: male 0.25–0.27; female 0.25; Width of eye: male 0.19–0.21; female 0.18; Width of pronotum: male 0.59–0.65; female 0.61; Length of pronotum: male 0.20–0.23, female 0.22.

Color. Ground color light brown ( Figs. 1e–f ). Head same color, eyes darker reddish-brown. Labium darker. Clypeogenal area of female dark brown to black, punctate; that of males punctate and of the same color as rest of head. Antennae pale. Pronotum brown, with narrow, pale transverse apical band spanning entire width, this band broadening at lateral margins of pronotum. Hemelytra with broad, dark band medially, extending onto embolium; apical and basal portions of embolium infuscated. Clavus brown, unicolorous except for small castaneous area basomedially; claval-corial commissure dark brown with narrow band along entire length. Scutellum pruinose along basal margin. Embolium well developed, pre- and post-nodal areas infuscated, lacking pruinosity. Corium brown, apical portion yellow-brown. Membrane subhyaline, brown, medial portion darker. Abdomen infuscated, legs yellow, mesotarsus with dark apical ring; metatarsus with darkened natatorial setae.

Structural characteristics. Ratio of body length/width: males 2.01; female 1.69. Pronotum slightly narrower than head, interocular space slightly wider than width of eye (synthlipsis/width of eye = 1.37). Ocular index: males 1.41; female 1.36. General facies of head (vertex, frons, and labium) of both sexes comparatively short. Antennae densely pilose, segments one and two very short, segment three long, spatulate. Pronotum broad and convex, well developed, nearly three times as wide as long (W/L: males 0.62/0.22; female: 0.61/ 0.22). Prothoracic lobe short, anterior and posterior angles rounded ( Fig. 9a ). Hemelytra with fine, transverse microsculpturing. Nodal furrow present, marked by diagonal suture not reaching wing margin. Prenodal embolar area long, well developed and wide; postnodal embolar area short, broad, not well developed. Short, stout spines distributed evenly over corium. Metathoracic wings reduced, spanning about two-thirds the length of hemelytra. Lateral spines and setae on abdominal segments IV–VIII; IV: one short, stout spine; V: three short spines and one long; VI: two short spines, one long; VII: two short spines, one long; VIII: six short spines (varying lengths), one long. Metaxyphus in both sexes extremely short, triangular, apex bluntly rounded ( Fig. 9b ).

Male foreleg ( Fig. 9c ): femur with two spines in basal third near ventral surface, one large seta in apical third towards dorsal surface, one small seta apically towards ventral surface. Tibia with one small seta medioventrally, two small setae ventroapically and two small setae in dorsoapical portion. Pala with three long setae on dorsal surface; palmar area with 11–13 setae in dorsal row and 14–15 setae in ventral row; ventral row setae more pronounced than dorsal row. Apex of pala with one thickened spinelike seta resembling a secondary claw. Palar claw ( Fig. 9d ) long, narrow with trough-shaped apical curve. Mesotarsal claws short, about one-third the length of mesotarsus.

Lateral lobes of abdominal tergum IV broadly rounded, right lobe slightly longer. Each lobe with one row of 13–15 setae along outer margin. Prestrigilar flap of abdominal tergum V quadrate, as in Figure 9e . Strigil elongate, subquadrate, with numerous densely packed combs. Median lobe of abdominal sternum VII ( Fig. 9f ) short, acutely pointed, lacking setae restricted to basolateral portion. Free lobe of abdominal tergite VIII ( Figs. 9g , 10a ) broad, quadrate, apex pointed, with 9–12 long setae along inner angle and apex; a single, long setae present near outer angle. Pars stridens processus cleaner ridges of abdominal segment VIII with indistinct raised ridges. Left paramere ( Figs. 10b–f ) comparatively short, shaft curved, apex curved upward. Tip of left paramere with hoodlike lateral processes, edges serrated ( Figs. 10b–d ). Right paramere ( Figs. 10b–f ) with long curved shaft, basal portion constricted near paramere base, tip of paramere with two lateral bulbous processes, as seen in dorsal view ( Figs. 10c–e ). Base of right paramere rectangular ( Figs. 10f–g ), with about 28 plectral ribs spanning medial to caudal portion. Aedeagus as in Figures 10c, e–f .

Distribution and habitat: ( Fig. 11 ). Indonesian New Guinea. Known only from the type locality and collected only from streams.

Discussion: The male genitalia of this species and Papuanecta minajerwioides sp. nov., are similar, however, there are several differences. The right paramere base of P. minajerwi is perpendicular to the shaft and rectangular. The shaft of P. minajerwi is also constricted basally and widens towards the middle of the shaft. The tip of the right paramere also differs from that of P. minajerwioides . The left parameres are similar in shape, but the distal lobes of the left paramere of P. minajerwi are rounded and serrated along the lower margin. The tip of the left paramere is blunt in P. minajerwi , whereas in P. minajerwioides the tip is distinctly pointed. Careful examination of the other described characters will allow separation of both sexes of the two species. Based on the general similarities in the male genitalic morphology and general tergal and sternal characters, P. minajerwi and P. minajerwioides are closely related species.

No additional specimens beyond the type series were recorded during this research. In the original description ( Tinerella and Polhemus 2005), the prestrigilar flap and free lobe of abdominal tergite VIII were incompletely illustrated. Illustrations of both structures are provided here ( Figs. 9e, g , 10a , respectively), along with that of the prothoracic lobe ( Fig. 9a ).

Figures

FIGURE 1. Dorsal habitus of Papuanecta species. a–b. P. sinistra (Chen), male and female. c–d. P. inelryjelnor sp. nov., male and female. e–f. P. minajerwi (Tinerella & Polhemus), male and female. g–h. P. minjerwioides sp. nov., male and female. Scale bars = 0.5mm.

FIGURE 8. Papuanecta minajerwi (Tinerella and Polhemus), holotype label, dorsal habitus. a. Type label. b. Holotype specimen, male, lateral habitus.

FIGURE 9. Papuanecta minajerwi (Tinerella and Polhemus). 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. g. Free lobe of abdominal tergite VIII. Scale bars = 0.1 mm. (Figs. c, d, f modified from Tinerella and Polhemus 2005).

FIGURE 10. Papuanecta minajerwi (Tinerella and Polhemus), male terminalia. a. Free lobe of abdominal tergite VIII, apex. b. Left paramere, lateral aspect, right paramere, dorsal aspect. c. Left paramere, lateral aspect, right paramere, lateral aspect. d. Left paramere, lateral aspect, right paramere lateral aspect. e. Left paramere, dorsolateral aspect, right paramere dorsal aspect. f. Left paramere, lateroventral aspect, right paramere lateral aspect. g. Pars stridens processus, base of right paramere. (Modified from Tinerella and Polhemus 2005).

FIGURE 11. Distribution of Papuanecta minajerwi (Tinerella and Polhemus).