Tibraca Stal, 1860

Tibraca Stal, 1860

Tibraca Stãl, 1860: 18 . - Stãl, 1867: 26. - Stãl, 1872: 30. - Lethieny & Severin, 1893: 132. - Kirkaldy, 1909: 72. - Costa Lima, 1947: 312.

Ogmocoris ; Costa Lima, 1947: 313 (syn.) (error).

Type species: Tibraca limbaliventris Stâl, 1860 (by monotypy)

Castaneous to dark caslaneous. Head long and acuminate. Anterolateral margins of pronotum yellowish. Body length arising 10.00 to 16.00 longoAbdominal width arising 6.00 to 8.00 long.

Head longer than the width between eyes and nearly as long as pronotum; anteocular portion longer than wide. Jugae and tylus subequal in length. Jugae progressively narrowing to apex. Antennae: segment I not attaining apex of head; segment ll1 the longest; I longer than II; V tanger than IV; segment IV slightly dorsoventrally depressed and longitudinally sulcated. Head in profile withjugae in a lower levei lhan tylus. Bucculae rectilinear, in proftle, weakly developed and evanescent at base ot'head. Rostrum attaining at least the first urosternite. Rostrum: segment I as long as bucculae but not hidden by them; segment II shorter than III and IV together. Dorsal punctures of head regularly distributed, ventral punctures concentrated c10se to antenniferous tubercles and base ofbucculae.

Pronotum trapezoidal, anterior angles distinctly toothed. Anterolateral margins rectilinear, entire and yellowish. Humeral angles not developed. Pronotum densely and uniformly punctured.

Thorax ventrally and irregularly punctured. Prosternum and mesosternum piceous. Anterior half of mesosternum carinate. A narrow row of white hairs aiong mesosternum. Metasternum shallowly concave. Each ostiolar ruga clavated. Evaporatory area matte. Tibiae dorsally sulcated. Femora and tibiae with piceous dots. Coxa, trocanters and tarsi immaculate. Basal angle of scutelum foveate, apex rounded not attaining posterior border of fifth segmento Posterior angle of corium acute reaching sixth segment of connexivum. Apex of radial vein with a small pale yellow callus. Hemelytralmembrane hyaline and infuscate, veins brown sometimes bifurcate. Well-exposed connexivum with concolorous punctures. Connexivum with mm·gins subcalosed and fuscous; postero-lateral angles weakly projected.

Ventral surface with smaller and more concentrated punctures than in the dorsal surface. Sutures of abdominal segments fuscous near lateral margins. Each trichobothrium separated by a longitudinal imaginary line tangential to the spiracles.

Male. Pygophore quadrangular, globose opening dorso-posteriorly. Dorsal rim excavated in an open "U". Postero-lateral angles rounded, slightly projected. Ventral rim forming two layers; the superior one expanded in 1 +1 breast-like structures, postero-ventrally directed and 1 +1 cylindrical arms dorsally-directed, each one beside segment X. Inferior layer carinated with I + I conical projections, that are close together; bristles sparsely distributed between superior and inferior layers. Segl11ent X (proctiger) cylindrical, apex rounded with I + I basal processes. Parameres reduced and trapezoidal in profile. Phallus dorso-ventrally depressed. Dorsal connectives short;processus capi/ali well developed. Phallotheca with 1+ 1 median, ventral, digitiform processes (processus phallothecae) almost parallel and shorter than processus conjunctivae I. Postero-Iateral angles of phalLotheca developed. Conjunctiva with two processes. Processus conjunctivae 1 in I + I divergent, slightly sclerotized arms beside processus phallolhecae I; processus conjunclivae 2 in I + I lateral digitiform structures. Vesica in a membranous collar ventrally excavated in an open "U" and dorsally with a shield-like processus (processus vesicae). Opening of vesica ventrally-directed, duclus seminis dislalis extremely long helicoidal and very delicate, normally noL preserved after dissecLion.

Fel11ale. Posterior border of gonocoxites 8 arched, l11esial borders parallel. Posterior border oflaterotergites 8 forl11ing an obtuse angle, spiracles absent. Apices of laterotergites 9 rounded and surpassing transverse band linking laterotergites 8 dorsally. Gonocoxites 9 trapezoidal, antero-lateral angles expanded into narrow and curved arms. Gonapophyses 9 with a pair of secondary thickening. Thickening of vaginal intima conical. Ductus receptacllli before and after vesicular area very long, but not as long as in Hypatropis Bergroth ( FERNANDES & GRAZlA 1996); dllctus helicoidal after vesicular area, and occasionally wound before vesicular area. Pars intermedialis with a basal sclerotized ring. Annular crests well developed and parallel. Capsula seminalis globose.

Comments. Tibraca belongs to a monophyletic group forl11ed by Mecocephala Dallas, 1851 , Paratibraca Campos & Grazia, 1995 , Glyphepomis Berg, 1891 , Parahypatropis Grazia & Fernandes, 1996 and Hypalropis Bergroth, 1891; the states of characters found in male genitalia, shared by these genera, represent the synapomorphies of the genera. BENVEGNÚ (1968) studied the pygophore and phallus of T. limbativentris , M. aeuminata Dallas, 1851 and Parameeoeephala foveala Benvegnú, 1968 and recognized the similarities among them. ln Tibraea and Meeoeephala, besides the biggest size ofthe body, the head is longer than wide, acuminate at apex, with a lighter band on pronotum and ostiolar ruga extending through 1 /3 of evaporatory area width.

The shorter rostrum and the absence of median abdominal sulcus separate Tibraea from Meeoeephala.

Distribution. Tibraea is found in Caribbean, Northwest Neotropical and Souheast Neotropical regions ( AMORIM & PIRES 1996). Its species have been reported from rice crops. T. limbaliventris has the widest known distribution of ali species ranging in Neotropical region from Southeast area to Northwest and Caribbean areas; T. similima is restricted to Ecuador, and T. exiglla , found in South Brazil, Argentina and Uruguay.

Key for identification of the species of Tibraca

1. Abdominal area between trichobothrial and lateral margins yellowish, sparsely punctured. Basal processes of proctiger, in males, in a posteriorly directed horn-like projection.. ......... ..... ..... .... ............ ...... 2 - Abdominal area between trichobothrial and lateral margins yellowish, with punctures almost as concentrated as in lhe abdomen. Basal processes of proctiger, in males, in a conical projection ...... ........ similima Barber

2. Small specimens (equal or shorter than 12.0 mm); legs red to dark red. Proeessus eonjuntivae I, in males, digitiform and dorsally curved at apex.. exigua sp.n. - Large specimens (equal or longer than 13.0 mm); legs castaneous, concolor with the body. Proeessus eonjunlivae I, in males, widened at apex, in profile .................................................. limbativentris Stâl