Belostoma ribeiroi De Carlo, 1933

Ribeiro, Josė Ricardo Inacio, 2007, A review of the species of Belostoma Latreille, 1807 (Hemiptera: Heteroptera: Belostomatidae) from the four southeastern Brazilian states, Zootaxa 1477 (1), pp. 1-70 : 50-52

Belostoma ribeiroi De Carlo, 1933

( Figs 14 ; 20C ; 24B )

Belostoma ribeiroi De Carlo, 1933: 95 , Fig. 3 .

Belostoma dufouri De Carlo, 1933: 96 , Fig. 4 .

Belostoma lundbladi De Carlo, 1963: 20 . Syn. n.

Types.— Belostoma ribeiroi was described based on male holotype ( Gruta do Tucum [?], Mato Grosso) deposited in MNRJ .

Material examined.— BRAZIL. Distrito Federal— *1 f (DZRJ-a 454): Brasília, Bacia do Riacho Fundo, 18.I.1996, ( V. Pires), J. R. I. Ribeiro det. 1999. Mato Grosso — * 1 m ( MNRJ 118): [without date and collector], J. A. de Carlo det. as B. dufouri, J. R. I. Ribeiro det. 1999, B. dufouri paratype. * 1 m ( MNRJ 119): Gruta do Tucum, 17.X.1908, (M. Ribeiro), J. A. de Carlo det., holotype. Minas Gerais — * 1 m ( DPIC 1209): Diamantina, 19.III.1994, (A. L. Melo), A. L. Melo det. *1 f ( DPIC 1619): same, Cachoeira Sentinela [“abaixo”], 19.III.1994, (A. L. Melo and N. Nieser), N. Nieser det. * 1 m ( DPIC 1785): same, [“riacho 1”], 20.III.1994, (A. L. Melo), A. L. Melo det. * 1 m ( MACN): Paracatu, Córrego Rico, 06.VII.1960, “Expedição Formosa”, J. A. de Carlo det. as B. lundbladi, J. R. I. Ribeiro det. 1999, B. lundbladi paratype. * 1 m / 1 f ( MNRJ 120): same, “DZ 54/62”, 06.VII.1960, “Exp. Formosa”, J. A. de Carlo det. as B. lundbladi, J. R. I. Ribeiro det. 1999, B. lundbladi holotype. 2 m / 2 f (DZRJ-a 508): Serra do Cipó-km 117 [1.100 m, 19 º 15’ 92” S, 43 º 32’ 86” W], 17.IV.1999, (A. L. Melo and J. R. I. Ribeiro), J. R. I. Ribeiro det. 1999. Santa Catarina — 1 m ( MACN): Nova Teutônia [300–500 m], IX.1951, (F. Plaumann), J. A. de Carlo det. as B. testaceopallidum, J. R. I. Ribeiro det. 1999.

Distribution.— BRAZIL: Distrito Federal ( Ribeiro 2005), Goiás ( Menke & Lauck 1962), Mato Grosso ( De Carlo 1933), Minas Gerais ( Nieser & Melo 1997) [but see De Carlo (1963)], Rio de Janeiro ( Ribeiro 2005), Santa Catarina ( Ribeiro 2005).

Description.—Measurements (m / f). Total length (from apex of head to apex of hemelytra at rest) 26.0– 32.3 / 27.8–31.2; largest width of body 12.8–15.3 / 13.3–14.8; median length of pronotum 4.80–5.40 / 4.80– 5.40; greatest pronotal width 9.20–10.40 / 8.64–10.64.

General coloration dark brown.

Body elliptical. Length of anteoculus 0.96–1.38 times length of interoculus; length of rostral segment I 0.82–1.04 times length of rostral segment II; anterior frontogenal suture longer than posterior frontogenal suture; clypeus reaching or not reaching ocular line (0–0.16 mm); vertex without longitudinal median carina; posterior interocular width 1.27–1.64 times length of anteoculus, and 1.43–1.82 times width of eye; eyes rounded. Pronotum usually with longitudinal median carina on its posterior portion; greatest pronotal width 1.76–1.97 times its length; scutellum reaching or not reaching nodal line (0–0.48 mm), usually with longitudinal median carina; prosternal keel not prominent, somewhat rounded and anteriorly projected at apex ( Fig. 14A ). Pilosity extending along the genital operculum, covering entire margin of connexivum and all or part of sternites.

Male genitalia ( Fig. 14C–E ).—Caudal portion of phallus flattened. Dorsal arms divergent, neither narrowing nor broading, rounded at apex in dorsal view; ventral diverticulum without dorsal caudal protuberance in dorsal and lateral views, and without ventroapical protuberance in lateral and ventral views; caudal lateral margins of ventral diverticulum convex, not sinuous in ventral view; width of ventral diverticulum equal to its length in ventral view.

Variation.—I examined the B. lundbladi holotype and paratype from Minas Gerais in the MNRJ, as designated by De Carlo. They show the prosternal keel weakly anteriorly projected and more acute at apex ( Fig. 14B ). Moreover, the dorsal arms are broader, narrowing apically in dorsal view ( Fig. 14F–H ) .

Notes on biology—According to Nieser and Melo (1997), B. ribeiroi has been most often collected at the edges of various running waters. The species apparently is not rare, and has so far only been found in Brazil.

Comparative notes.—The history of B. ribeiroi has become somewhat confused. De Carlo (1938) and Lauck (1963) observed specimens with rostral segment I shorter than II. However, in De Carlo’s (1960) specimens, rostral segment I is slightly longer than II.

Belostoma lundbladi keys to B. ribeiroi in Nieser and Melo’s (1997: 59) key. Both B. lundbladi and B. ribeiroi have similar body lengths and phallic traits. Nevertheless, De Carlo (1963) differentiated these two species only on the basis of differences in rostral lengths. The differences between the types of the two species in rostral lengths are small and well within the limits of variability found for other specimens studied here. I do not consider these differences significant, and I am confident in synonymizing B. lundbladi with B. ribeiroi , as suggested by Nieser and Melo (1997).

Belostoma ribeiroi might be confused with B. testaceopallidum . In both have the pilosity covers the entire margin of connexivum and part or all of the sternites. However, according to Lauck (1963) and Nieser and Melo (1997), B. ribeiroi can be readily distinguished from B. testaceopallidum by its total length being more than twice its width and by the caudal lateral margins of ventral diverticulum not being sinuous in ventral view ( Fig. 14C–H ).

Figures

FIGURE 3. Belostoma aurivillianum (Montandon, 1899). 3A–B, Prosternal keel (lateral view): 3A, Specimen from Roraima (INPA 0020902). 3B, Specimen from Pará (SEMC 6479). 3C–J, Phallus: 3C–E, Specimen from Pará (INPA 0020991). 3F–H, Specimen from Rondônia (MZSP). 3I–J, Specimen with danified phallus from São Paulo (MACN). 3C, 3F and 3I, Dorsal views. 3D, 3G and 3J, Ventral views. 3E and 3H, Lateral views. Scale bar: 1.00 mm.

FIGURE 4. Belostoma bergi (Montandon, 1899) and B. bosqi De Carlo, 1932. B. bergi. 4A–B, Prosternal keel (lateral view): 4A, Specimen from São Paulo (MNRJ 165); 4B, Specimen from Corrientes, Argentina (MNRJ 166). 4C–H, Phallus: 4C–E, Specimen from Corrientes, Argentina (MNRJ 166). 4F–H, Specimen from São Paulo (MNRJ 164). B. bosqi. 4I–J, Prosternal keel (lateral view) of the specimens from Minas Gerais (DPIC). 4K–P, Phallus: 4K–M, Specimen from Minas Gerais (DPIC). 4N–P, Specimen from Mato Grosso (SEMC). 4C, 4F, 4K, and 4N, Dorsal views. 4D, 4G, 4L, and 4O, Ventral views. 4E, 4H, 4M, and 4P, Lateral views. Scale bar: 1.00 mm.

FIGURE 14. Belostoma ribeiroi De Carlo, 1933. 14A–B, Prosternal keel (lateral view): 14A, Specimen without a more precise locality (MNRJ 106). 14B, Specimen from State of Minas Gerais (MNRJ 120). 14C–H, Phallus: 14C–E, Specimen (holotype) from State of Mato Grosso (MNRJ 119). 14F–H, Specimen from State of Minas Gerais (MNRJ 120). 14C and 14F, Dorsal views. 14D and 14G, Ventral views. 14E and 14H, Lateral views. Scale bar: 1.00 mm.

FIGURE 20. Dorsal habitus. 20A, Belostoma noualhieri Montandon, 1903: specimen from State of Rio Grande do Sul (MNHN, holotype). 20B, B. plebejum (Stål, 1860): specimen from State of Espírito Santo (MNRJ 170). 20C, B. ribeiroi De Carlo, 1933: specimen from State of Rio de Janeiro (MACN 3680). 20D, B. sanctulum Montandon, 1903: specimen from State of Espírito Santo (HNHM). Scale bar: 5.00 mm.

FIGURE 24. Geographic distribution map of Belostoma species in southeastern Brazil. 24A, = B. foveolatum, = B. horvathi. 24B, = B. plebejum, = B. ribeiroi, = B. sanctulum.