Martarega nessimiani Barbosa & Rodrigues

Barbosa, Julianna Freires & Rodrigues, Higor D. D., 2013, A new species of Martarega White, 1879, with new distributional records of Notonectidae (Hemiptera: Heteroptera: Nepomorpha) from Brazil, Zootaxa 3682 (4), pp. 534-540 : 535-538

Martarega nessimiani Barbosa & Rodrigues , sp. nov.

( Figures 1–8 )

Type material. Holotype: Brazil, State of Minas Gerais, Luz Municipality, Ribeirão Jorge Grande (19º40’13”S / 45º36’37”W), 27.IV.2011, (H.D.D. Rodrigues): 1 m, brachypterous ( MZUSP). Paratypes: Same data of holotype, 1 m and 9 f, brachypterous ( DZRJ); same data of holotype, except 13.X.2010: 5 m and 3 f, brachypterous ( DPIC); same data of holotype, except 13.III.2010 (H.D.D. Rodrigues; G.J.C. Vianna): 3 f, brachypterous, 1f, macropterous ( DPIC). Brazil, State of Pará, Canaã dos Carajás, FLONA de Carajás, Serra Sul, Lagoa S11 A-B, XI. 2011 (Lab. Limnologia UFRJ): 1 f, brachypterous ( DZRJ); Márgem, R. Claro, Jataí, GO-Faz, XI.1962 [ Brazil, State of Goiás, Jataí Municipality, margem, Rio Claro, faz (?), XI.1962]: 3 m and 2 f, brachypterous, 2 f, macropterous ( MZUSP).

Description. HOLOTYPE (brachypterous male)

Measurements. Body length (from apex of head to apex of hemelytra at rest): 5.70; vertex median axis length: 0.24; vertex greatest width: 0.34; eye width: 0.62; ocular commissure length: 0.28; frons width: 0.14; head median axis length: 0.52; head greatest width: 1.24; ocular index: 0.75; pronotum median axis length: 0.38; pronotum greatest width: 1.44; scutellum median axis length: 0.60; scutellum greatest width: 0.80; hemelytra length: 4.86; extension of hemelytral process: 0.42; membrane length: 0.66.

Color. Setae light to dark gray. Setae of legs and external lateral margin of connexivum yellow. Setae on mesosternum, between intermediate legs, dark brown. General body color yellowish. Eyes red, dorsally; slightly darker ventrally. Labrum and line along length of third rostral segment light brown; fourth segment dark brown. Hemelytra opaque with hyaline stripes. Joint between intermediate femur and trochanter outlined in dark brown. External lateral margin of ventropleurites with median region stained with brown.

Head. Head width 2.3 times its median length and 3.6 times vertex width; length 1.4 times pronotum length. Anterior margin of vertex protruding before eyes; vertex wider than long. Ocular commissure a little shorter than one-half width of one eye, and longer than vertex length. Frons wide with a group of sparse setae. Tylus slightly inflated. Third rostral segment with few setae along ventral surface.

Thorax. Body length 15 times pronotum length. Posterior margin of pronotum straight in median portion, slightly angulated with thin setae, becoming rounded near foveae; greatest pronotum width 3.8 times its median length. Hemelytra with two stripes ( Fig. 1 ): a longitudinal median stripe narrow, with superior and inferior margin continuous, originating near base of hemelytra and extending to membranal suture with costal margin; second stripe originating at base of hemelytral process, with long setae along its length, extending anteriorly onto onefourth of hemelytra. Hemelytral process extending onto 0.63 of membrane length. Scutellum wider than long and longer than pronotum. External margin of fore femur with a small spine at halfway of its length. Intermediate femur with short bristles restricted to median axis of ventral surface. Ventral surface of mesotrochanter slightly tumid, with a rounded patch of thin setae centered, situated distinctly below base of joint between femur and trochanter; lateral external margin slightly angled to straight ( Fig. 2 ). Metaxyphus trilobite ( Fig. 3 ); apex of metaxyphus overcoming the apex of ventropleurites. Hind trochanter with continuous margin. Internal margin of hind femur with 20 setae.

Abdomen. Ventral abdominal keel with hairs distributed throughout lateral surface. Genital capsule not produced; right clasper strongly rounded ( Fig. 4 ); left clasper rectangular with rounded edges and longitudinal groove ( Fig. 5 ).

PARATYPES (brachypterous male / brachypterous female). Measurements. Body length (from apex of head to apex of hemelytra at rest): 5.65–5.89 / 6.05–6.25; vertex median axis length: 0.24–0.30 / 0.22–0.30; vertex greatest width: 0.30–0.34 / 0.32–0.37; eye width: 0.61–0.64 / 0.63–0.70; ocular commissure: 0.29–0.32 / 0.28– 0.32; frons width: 0.12–0.15 / 0.19–0.24; head median axis length: 0.54–0.62 / 0.52–0.60; head greatest width: 1.21–1.28 / 1.30–1.40; ocular index: 0.69–0.75 / 0.64–0.73; pronotum median axis length: 0.38–0.44 / 0.40–0.44; pronotum greatest width: 1.40–1.46 / 1.45–1.58; scutellum median axis length: 0.63–0.72 / 0.64–0.80; scutellum greatest width: 0.85–0.90 / 0.80–0.96; hemelytra length: 4.70–5.00/ 5.08–5.20; extension of hemelytral process: 0.40–0.50/ 0.45–0.60; membrane length: 0.56–0.65/ 0.68–0.84.

Brachypterous male. Color. General color similar to holotype. Setae light to dark brown. Fourth rostral segment dark brown to black. Fore and hind femora with a short brown stain near base. Intermediate femur with a brown stain restricted to median axis of ventral surface.

Head. Head width 2.1 to 2.3 times its median length, and 3.6 to 3.8 times vertex width; length 1.3 to 1.5 times pronotum length. Ocular commissure shorter or equal to one-half width of one eye (0.45–0.51) and longer or equal to vertex length.

Thorax. Body length 13.2 to 14.6 times pronotum length. Pronotum width 3.3 to 3.7 times its median length. Hemelytral process extending onto 0.67 to 0.78 membrane length. Internal margin of hind femur with 21 to 26 setae.

Brachypterous female. Color. General color similar to holotype. Membrane apex yellow to spotted with brown. Fourth rostral segment dark brown to black. Fore and hind femora with a short brown longitudinal stain near base. Intermediate femur with a brown longitudinal stain restricted to longitudinal axis.

Head. Head width 2.3 to 2.7 times its median length; head length 1.2 to 1.45 times pronotum length. Ocular commissure a little shorter than one-half width of one eye (0.43–0.48) and longer to equal vertex length. Frons wider than in males. Tylus slightly inflated. Rostrum glabrous.

Thorax. Body length 14.5 to 15.3 times pronotum length. Posterior margin of pronotum straight in median portion, slightly angulated with thin setae, becoming rounded near foveae; pronotum width 3.6 to 3.9 times its median longitudinal axis. Hemelytra with three stripes ( Fig. 6 ): median longitudinal stripe wide at first one-third of length followed by a slight constriction, narrowing along its length, originating near base of hemelytra and extending to membranal suture with costal margin; stripe at base of hemelytral process angular, with long setae along length, extending anterad for just over one-fourth hemelytra length; a third stripe originating at hemelytral suture near apex of stripe of hemelytral process, extending anterad to near base of hemelytra. Section between embolium ending and membrane beginning slightly enlarged when observed dorsally; started by a translucent spot and limited by a short brown band at costal margin ( Fig. 8 ). Hemelytral process shorter than in males, extending onto 0.65 to 0.77 of membrane length. External lateral margin of fore femur with a long setae just over one-half of femur length. Mesotrochanter smooth. Internal margin of hind femur with 19 to 23 setae.

PARATYPE (macropterous female). Measurements. Body length (from apex of head to apex of hemelytra at rest): 6.38–6.55; vertex median axis length: 0.26–0.32; vertex greatest width: 0.30–0.34; eye width: 0.68–0.69; ocular commissure: 0.29–0.34; frons width: 0.18–0.20; head median axis length: 0.56–0.66; head greatest width: 1.34–1.36; ocular index: 0.57–0.67; pronotum median axis length: 0.55–0.56; pronotum greatest width: 1.67–1.76; scutellum median axis length: 1.04–1.20; scutellum greatest width: 1.44–1.50; hemelytra length: 5.45–5.50.

Color. General color similar to holotype.

Head. Head width 2.1 to 2.4 times its length; head length 1 to 1.2 times pronotum length. Ocular commissure equal to a little shorter than one-half width of one eye (0.44–0.50) and longer than vertex length.

Thorax. Pronotum width about 3 times its median length. Hemelytra with a single median longitudinal stripe ( Fig. 7 ).

Taxonomic notes. Specimens of M. nessimiani sp. nov. are quite similar to specimens of M. brasiliensis Truxal, 1949 , except for the shorter length of M. brasiliensis [males with 5.20–5.35 and females with 5.60–5.80 ( Truxal 1949)]. Both species can be identified mainly by a patch of thin and yellow setae on the ventral surface of the male mesotrochanter; and the female hemelytra with three hyaline stripes. Apart from the lengthes, these species are easily distinguished by features of the male and the female. Males of M. nessimiani sp. nov. have wide frons (0.12–0.14); tylus more inflated; ventral surface of rostrum glabrous with a few setae; and a patch of thin rounded setae on the mesotrochanter. Females of this species have a median longitudinal stripe of hemelytra distinctly narrower than in M. brasiliensis , and a stripe originating at the hemelytral process with an angular shape. Males of M. brasiliensis have a narrow frons (0.09–0.11); tylus not inflated; apex of second rostral segment and entire ventral surface of third rostral segment pubescent ( Fig. 9 ); a little wider median longitudinal stripe ( Fig. 10 ); patch of thin setae on mesotrochanter with irregular shape ( Fig. 11 ); and small differences in the shape of the claspers ( Fig. 12, 13 ). Females of M. brasiliensis show a wider median longitudinal stripe and stripe of hemelytral process straight to slightly convex ( Fig. 14 ).

Distribution. So far, known in three Brazilian states, in North (State of Pará), Central-West (State of Goiás), and South regions (State of Minas Gerais) ( Fig. 13 ).

Etymology. The species epithet is named in honor of Jorge L. Nessimian (Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil), in recognition of his contributions to the knowledge of aquatic insects of Brazil.

Figures

FIGURES 1 – 14. Martarega nessimiani sp. nov. (1 – 8): (1) Brachypterous male hemelytra in lateral view, (2) male mesotrochanter, (3) male ventropleurites and metaxyphus, (4) male genital capsule in lateral view showing right clasper, (5) male genital capsule in lateral view showing left clasper, (6) brachypterous female hemelytra in lateral view, (7) macropterous female hemelytra, (8) female in lateral view. Martarega brasiliensis (9 – 14): (9) rostral segments in frontal view, (10) brachypterous male hemelytra in lateral view, (11) male mesotrochanter, (12) male genital capsule in lateral view showing right clasper, (13) male genital capsule in lateral view showing left clasper, (14) female hemelytra in lateral view.