Tachygonidius fluminensis, Vanin, Sergio Antonio & Mermudes, José Ricardo M., 2007

Vanin, Sergio Antonio & Mermudes, José Ricardo M., 2007, Two new Tachygonidius species from the Atlantic coast of Brazil (Coleoptera: Curculionidae), Zootaxa 1415, pp. 57-64 : 57-61

Tachygonidius fluminensis , sp. nov.

( Figs. 1–6 , 8–11 )

Type series: Holotype male (dissected, right posterior leg missing) “Restinga da Barra de Maricá, Maricá, RJ, Brasil; Data: 1995; Coletor: Ricardo Monteiro”. Paratypes: same data, 1 female; same locality and collector, but “1992; minador de folha de Ochnaceae ”, 1 male, 1 female. Types deposited in the collection of the Museu de Zoologia, Universidade de São Paulo ( MZSP).

Description. Body sub-rhomboidal ( Fig. 1 ), broad, about 1.3 times as long as wide (including head), dark reddish with black discal patches on pronotum and elytra; under surface of body black, densely clothed with white pectinate scales.

Length (rostrum excluded), males: 3.6 mm; females: 3.7–3.9 mm.

Head ovate, dorsally punctate and with ochreous and white pectinate scales; in frontal view slightly higher than wide; eyes dorsally connate, ventrally becoming separate, inter-ocular space narrow and triangular; rostrum about as long as head and nearly twice as long as wide, lateral margins sub-parallel, slightly widened toward flattened apex; frons and basal 2/3 of rostrum densely clothed with white pectinate scales, triangular area of middle-third portion and distal third bare and shining. Antenna (Fig. 3) yellow, funicle with articles 1 to 3 elongate, 1 about as wide as scape, about as long as article 2 but nearly twice as broad, 4 to 6 transverse and increasing progressively in width; club elongate-oval, about 3 times as long as wide, and as long as length of articles 1 to 4 combined; scape and article 1 of funicle with a few white pectinate scales, other articles of funicle with erect setae; club densely clothed with recumbent short setae, resulting in silky aspect.

Pronotum sub-pentagonal, transverse, about 0.6 times as long as wide, with lateral margins rounded; pronotal disc flattened, coarsely and irregularly punctate, except along narrow, elongate-oval median space, with a short and weak longitudinal carina at middle. Sides of prothorax, anterior and posterior angles of pronotum densely clothed with ochreous and white pectinate scales; disc and sides of prothorax also with sparse, long and erect black setae.

Elytra cordiform, slightly wider than long, weakly constricted behind humeri, humeri pronounced and bulbous, feebly depressed on disc, with coarse, deep, confluently punctate striae, and weakly raised discal interstriae; each elytron with one prominent callus formed by confluence of interstriae in front of elytral declivity; elytra with sparse short, decumbent yellowish setae, and sparse long and erect black setae; sutural interstriae with one row of white scales, smaller, pectinate and decumbent in basal 2/3, and longer, white crossing setae in distal 1/3; this row of scales margined on each outer side by one row of brightly yellow pectinate scales; white pectinate scales forming, faint oblique band from elytral margin near posterior coxa to about stria V, and additional yellow or white pectinate scales forming rows or clusters in front of humeri, elytral base, and margins and declivous areas of elytral apices.

Anterior (Fig. 4) and median legs yellowish, in some specimens with one dark red irregular band near femoral apex, densely clothed with yellow and white pectinate scales (Fig. 5), and long, erect, white and black setae, mainly on tibiae; posterior legs with femora reddish, with sparse, long, erect, black setae, and tibiae darker with dense fringe of long, curved brownish setae on the inner margin, and shorter stiff setae on outer margin; surface of hind tibiae with 3 –15 white pectinate scales ( Fig. 2 ); posterior tarsi with dorsal and lateral sides of articles 1–3 with one dense brush black and white setae. Posterior femora slender ( Fig. 2 ), nearly 10 times as long as wide, armed with about 17 small to medium sized teeth and 1 long tooth, widest near distal ¼, which bears the largest tooth. Tibia elongate-triangular ( Figs. 2 and 6 ), about 3.2–3.3 times as long as wide, flattened, inner margin crenulated and feebly arcuate, outer margin weakly crenulated on about basal third and nearly smooth on distal two-thirds, strongly curved and with a large, concave notch near apex. Posterior tarsomeres 1–3 with dense brush of white and yellowish hairs.

Sexual dimorphism. Declivous portion of pygidium oblique and transverse, deeper in male ( Fig.8 ), about 2.7 times as wide as long, in female less deep ( Fig.9 ), about 4.0 times as wide as long.

Male genitalia. Median lobe ( Figs. 10 and 11 ) about 2.3 times as long as wide (apophysis excluded), expanded in apical 1/3 and constricted sub-apically, apex with two obtuse prominences; basal apophysis about as long as median lobe.

Etymology: “ fluminensis ”, Latin, adjective that refers to those who are born in the state of Rio de Janeiro, the place where the type specimens were collected, in the city of Marambaia. Geographic distribution: only known from the type locality.

Type locality: BRAZIL. Rio de Janeiro, Restinga da Marambaia. Remarks. See below under Tachygonidius paulensis .

Figures

FIGURE 1 – 2. Tachygonidius fluminensis sp. nov., (1) habitus, female paratype (length: 3.9 mm). (2), right posterior leg, female paratype.

FIGURE 6 – 7. hind left tibia, dorsal view, setae omitted, (6) Tachygonidius fluminensis sp. nov., female paratype; (7) Tachygonidius paulensis sp. nov., female holotype (scale bar = 0.5 mm).

FIGURE 8 – 11. Tachygonidius fluminensis sp. nov., declivous region of pygidium: male holotype (8); female paratype (9) (scale bar = 0.5 mm); aedeagus: dorsal (10) and lateral (11) views, male holotype (scale bar = 0.2 mm).