Carvalhoiella acuminata Rodrigues and Sites

Rodrigues, Higor D. D., Sites, Robert W. & Giehl, Nubia F. S., 2016, Revision of the Neotropical genus Carvalhoiella De Carlo (Heteroptera: Nepomorpha: Naucoridae), Zootaxa 4138 (3), pp. 577-590 : 578-581

Carvalhoiella acuminata Rodrigues and Sites , NEW SPECIES

( Figs. 1–6 , 32 )

Description. Macropterous female. HOLOTYPE, length 9.84; maximum width 6.64. Paratypes (n = 4), length 9.28–9.76 (mean = 9.54); maximum width 6.24–6.56 (mean = 6.40). General shape oval, widest across embolia; overall coloration dorsally dark brown, with parts of pronotum, scutellum, embolium, and connexiva yellow ( Fig. 1 ); ventral surface mostly dark brown; legs, lateral part of propleura, and abdominal laterosternites yellow ( Fig. 2 ).

Head. Length 1.68, maximum width 2.80. Lightly punctate, brown with wide dark brown median area narrowing anteriorly; several setae near inner margins of eyes; projecting beyond eyes 9.52% of head length. Eyes dark brown, length 1.4× width, length/width 1.12/0.80, inner margins shallowly convergent, lateral margins rounded, synthlipsis 1.12. Labrum brown, broadly rounded distally, width 1.5× length, width/length = 0.60/0.40. Labium with three visible segments, darkening distally from two yellowish basal segments to dark brown distal segment, short, extending 0.30 beyond labrum. Antenna short, length 0.68, hirsute mainly in last two antennomeres, not extending beyond lateral margin of eye, relative lengths 4:9:11:8.

Thorax. Pronotum broad, brown, lateral margins yellow in posterior half; scattered dark brown punctation; transverse sulcus setting off band in posterior 1/4; maximum width 5.76, length at midline 1.76; posterior margin straight in midline, slightly rounded laterally; lateral margins convex, convergent anteriorly; posterolateral corners rounded; rugosity especially evident anteromedially. Scutellum dark brown, with yellow areas near anterolateral corners; punctate; width 3.76, length at midline 1.92. Mesoscutum partially exposed behind pronotum with head/ pronotum deflexion. Hemelytra dark brown with lighter mottling; punctate; length 7.20 (chord measurement). Clavus distinct, dark brown with lighter mottling. Embolium well delineated, lateral margins convex throughout, convexity stronger in posterior 2/3, yellow anteriorly transitioning to dark brown area in posterior third, maximum width 1.04, length 3.20. Hemelytra attaining tip of abdomen; venation not evident, membrane of underlapping wing (left) not punctured. Hindwings well developed. Ventrally, prosternum with mid-ventral carina. Propleuron laterally with extensive yellow, glabrous area extending 1/2 distance to mesal margin; golden setae posteriorly, near inner margin of glabrous area. Mesobasisternum without medial carina, and with golden setae near midline. Mesosternellum with lateral margins slightly thickened. Mesopleuron with golden setae on lateral margin. Metasternellum (=metaxyphus) with longitudinal carina, apex obtuse.

Legs. All segments yellow except brown protibia and tarsus, and distal portion of third tarsomere of middle and hind legs. Profemur with scattered brown spots in posterior 3/4 on dorsal and ventral surfaces; anterior margin with dense pad of golden-brown setae. Protibia with inner surface flattened; tarsus one-segmented; single claw minute, indistinct. Middle and hind coxae covered with pale brown, recumbent setae. Meso- and metafemora with two posteroventral rows of peglike spines, becoming obsolete proximally. Meso- and metatibiae with rows of stout reddish brown spines, 2 transverse rows of long, stout spines at apex, meso- and metatibiae and tarsi with long, golden brown swimming hairs. Meso- and metapretarsal claws paired, slender, evenly curved. Leg measurements as follows: foreleg, femur 2.36, tibia 1.68, tarsus 0.48; middle leg, femur 2.40, tibia 2.08, tarsomeres 1–3, 0.20, 0.32, 0.48; hind leg, femur 3.04, tibia 3.52, tarsomeres 1–3, 0.28, 0.56, 0.76.

Abdomen. Connexiva III–VI exposed laterally beyond hemelytra; laterotergites III–VI each brown anteriorly, yellow posteriorly, lateral margins smooth, with small tuft of elongate hairs posteriorly; posterolateral corners of II–V slightly acute, VI rounded. Venter densely pilose, except broad marginal band on laterosternites and median part of mediosternites V–VII naked, shiny. Subgenital plate (=mediosternite VII) with lateral margins convergent posteriorly and truncate medially ( Fig. 3 ).

Macropterous male. Paratypes (n = 10), length 8.96–9.60 (mean = 9.28); maximum width 6.08–6.56 (mean = 6.35). Similar to female in general structure and coloration, except as follows: Tergum V asymmetrical, with posterior margin displaced slightly to left. Tergum VI asymmetrical with concavity larger on right lateral margin, without accessory genitalic process or posterior protuberance. Terga VII–VIII, including medial lobes of tergum VIII (=pseudoparameres) symmetrical; medial lobes of VIII directed posterolaterally, apices rounded ( Fig. 4 ). Pygophore brown, elongate golden setae concentrated on posterior half of lateral margins and apex; anterior margin between parameres rounded. Parameres symmetrical, teardrop-shaped ( Fig. 5 ). Phallosoma elongate, ventrally with a pair of sclerotized lobes, both unarmed with teeth; right lobe overlaps left lobe ( Fig. 6 ).

Diagnosis and comparative notes. Carvalhoiella acuminata sp. nov. can be distinguished from its congeners by the dark brown ventral color pattern of the body ( Fig. 2 ) and by the posteriorly convergent female subgenital plate ( Fig. 3 ). This new species is most similar to C. stysi because both have the dark brown ventral coloration; however, the latter has the posterior margin of the female subgenital plate broadly concave medially ( Fig. 28 ).

Etymology. Acuminatus (Latin), pointed, tapering to a point; referring to the female subgenital plate acuminate posteriorly.

Distribution. This species occurs on the west side of the Araguaia-Tocantins Basin, in the state of Mato Grosso, central-western Brazil ( Fig. 32 ).

Type material examined. All specimens macropterous. Holotype: ♀ ( MZUSP), BRAZIL, Mato Grosso, Nova Xavantina, waterfall at Córrego Chupador, 18.IX.2010, H. Cabette et al. col. Paratypes: 2♂ ( MZUSP), 4♂, 1♀ ( CZNX), 1♂ (UMC), same data as holotype; 1♂ ( MZUSP), 1♂ ( CZNX), 1♂, 1♀ (UMC), same data as holotype, except 29.IV.2011; 1♂, 1♀ ( MZUSP), 1♂ ( CZNX), 1♀ (UMC) waterfall at Córrego Buriti, 14°45’04.1”S / 52°33’11.0”W, 27.IV.2011, H. Cabette et al.; 1♂ ( MZUSP), same data, except 19.IX.2010; 2♂ ( MZUSP), waterfall at Córrego Duílio, 17.IX.2010, H. Cabette et al. col.; 1♀ ( MZUSP), same data, except downstream, 14°48’18.8”S / 52°30’10.7”W, 01.V.2011; 1♂ ( MZUSP), same data, except N.F.S. Giehl col.

Figures

FIGURE 32. Distribution records of all species of Carvalhoiella.

FIGURES 1 – 6. Carvalhoiella acuminata sp. nov. (1) Dorsal and (2) ventral habitus of holotype, (3) terminal abdominal sterna of holotype, (4) terminal abdominal terga of male paratype (genital capsule removed), (5) genital capsule of male showing pygophore, phallosoma, and parameres, (6) ventral side of phallosoma. Size bar = 0.5 mm and pertains only to Figs. 5, 6.

FIGURES 26 – 31. Carvalhoiella stysi. (26) Dorsal and (27) ventral habitus of female, (28) terminal abdominal sterna of female, (29) terminal abdominal terga of male (genital capsule removed), (30) genital capsule of male showing pygophore, phallosoma, and parameres, (31) ventral side of phallosoma. Size bar = 0.5 mm and pertains only to Figs. 30, 31.