Belostoma elongatum Montandon, 1908

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 : 28-29

Belostoma elongatum Montandon, 1908

( Figs 7M–P ; 19A ; 23B )

Belostoma elongatum Montandon apud Lauck, 1962: 299.

Belostoma boscii: De Carlo, 1930: 112 , plate V ( Fig. 11 ), plate VII (Figs 27–28).

Types.—According to Lauck (1962) and Schnack (1976), B. elongatum was described based on syntypes (Asunción and Apa River, Paraguay) deposited, respectively, in HNHM and MIZT. These specimens have not been examined.

Material examined.— ARGENTINA. 1 m / 1 f ( HMHN): Chaco, Resistencia –“nr. P-B 313”, “Hungariin Soil-zool. Exp.”, 23.XII.1965, ([?] Mahunka), J. R. I. Ribeiro det. 1999. *1 f ( MZSP): Salta, Tartagal , XII.1961, (A. Martinez), J. R. I. Ribeiro det. 1999. BRAZIL. Mato Grosso — 3 m ( MNRJ 96 ): Cáceres , 02.XII.1955, (M. Alvarenga), J. A. de Carlo det. * 1 m ( MNRJ 95 ): same, I.1941, (“ Pass’i ” [?]), J. A. de Carlo det. 1 m ( DPIC 3221 ): Cuiabá, Coxipó , 12.X.1988, (U. M. Bezerra), A. L. Melo det. * 2 m / 3 f ( MNRJ 93 ): Urucum , I.1955, (“ Comissão I. O. Cruz ”), J. A. de Carlo det. Mato Grosso do Sul — * 1 m ( DPIC 567 ): Corumbá , 17.XI.1992, (Fabiana [?] and T. P. S. Sereno), J. R. I. Ribeiro det. 1999. 5 m / 5 f ( MNRJ 90 ): Salobra , I.1955, (“ Comissão I. O. Cruz ”), J. A. de Carlo det. * 2 f ( SEMC): same, I.1955, (C. A. Camargo [this specimen has been exchanged with P. F. S. Pereira]), J. R. I. Ribeiro det. 1999. Minas Gerais — *1 f ( DPIC 419 ): Belo Horizonte, Pampulha Lake , 16.XII.1991, (A. L. Melo), N. Nieser det. 1 f ( DPIC 201 ): Lagoa Santa , 10.III.1990, (A. Pelli), A. L. Melo det. Piauí — 1 f ( MNRJ 94 ): Teresina , I.1960, (O. Fontoura and C. S. Ferreira), J. R. I. Ribeiro det. 1999. Rondônia — *1 f ( MZSP): Príncipe da Beira , 19.XI–03.XII.1967, (G. R. Kloss), J. R. I. Ribeiro det. 1999. PARAGUAY. * 1 m ( MZSP): Puerto Casado , XII.1958, ([?] Martinez), J. R. I. Ribeiro det. 1999.

Distribution.— ARGENTINA: Buenos Aires ( De Carlo 1930), Catamarca ( De Carlo 1930), Chaco ( De Carlo 1930), Corrientes ( De Carlo 1930), Entre Ríos ( De Carlo 1930), Mendoza ( Lauck 1962), Misiones ( Lauck 1962), Salta (new record), Santa Fe ( Lauck 1962), Santiago del Estero ( Lauck 1962). BOLIVIA: Roboré ( Lauck 1962), Santa Cruz ( Lauck 1962), Pando ( Lauck 1962) [as “Chiquitos”]. BRAZIL: Mato Grosso (new record), Mato Grosso do Sul (new record), Minas Gerais (new record in southeastern Brazil), Piauí (new record), Rio Grande do Sul ( Lanzer 1976), Rondônia (new record). COLOMBIA ( De Carlo 1930). COSTA RICA ( De Carlo 1930). CUBA ( De Carlo 1930). DOMINICAN REPUBLIC: Santo Domingo ( De Carlo 1930). GUATEMALA ( De Carlo 1930). GUYANAS [?] ( De Carlo 1930). MÉXICO ( De Carlo 1930). PANAMA ( De Carlo 1930). PARAGUAY: Asunción ( De Carlo 1930), Central ( Lauck 1962), Guairá ( Lauck

1962), Paraguari ( Lauck 1962), Puerto Casado (new record). PERU: Junín ( Lauck 1962). URUGUAY ( De Carlo 1930): Artigas ( Ruffinelli & Pirán 1959), Canelones ( Ruffinelli & Pirán 1959), Montevideo ( Ruffinelli & Pirán 1959), Rivera ( Ruffinelli & Pirán 1959), Sierra de Mahoma ( Lauck 1962) [as “ San José ”], Treinta y Tres ( Ruffinelli & Pirán 1959).

Description.—Measurements (m / f). Total length (from apex of head to apex of hemelytra at rest) 33.3– 38.4 / 36.7–40.9; largest width of body 13.8–15.3 / 14.4–15.5; median length of pronotum 5.86–6.86 / 6.14– 6.79; greatest pronotal width 10.29–11.57 / 10.71–11.86.

General coloration yellowish brown. Anterior portion of pronotum usually with two dark longitudinal stripes, each parallel to lateral borders.

Body elongate and strongly straight. Length of anteoculus 1.03–1.37 times length of interoculus; length of rostral segment I 1.11–1.41 times length of segment II; anterior frontogenal suture usually longer than posterior frontogenal suture; clypeus not reaching ocular line (0.14–0.43 mm); vertex without ongitudinal median carina; posterior interocular width 1.00–1.17 times length of anteoculus, and 1.11–1.57 times width of eye; eyes rounded. Posterior part of pronotum occasionally with longitudinal median carina; greatest pronotal width 1.69–1.81 times its length; scutellum reaching nodal line, occasionally with weakly longitudinal median carina; prosternal keel prominent, somewhat rounded at apex ( Fig. 7M ). Pilosity not extending along genital operculum, usually covering about half of connexivum.

Male genitalia ( Fig. 7N–P ).—Dorsal arms anteriorly broad, narrowing gradually toward apex in dorsal view; ventral diverticulum with dorsal caudal protuberance in dorsal and lateral views, and with developed ventroapical protuberance in lateral and ventral views; caudal lateral margins of ventral diverticulum sinuous in ventral view; width of ventral diverticulum about 1.3 times its length in ventral view.

Comparative notes.—As defined by De Carlo (1930, 1938) and Schnack (1976), in B. elongatum the anteoculus and interoculus are subequal. As argued by Lauck (1962), and based on results herein reported, these structures may be subequal in some specimens, but this may be the result of imprecise measurements (A. L. Melo, pers. comm.). Thus, this character cannot be considered diagnostic for this species. As mentioned by Lauck (1962), it would appear that this is a species complex.

The specimens studied by Lauck (1962) and Schnack (1973, 1976) agree with the specimens studied here, which possess the greatest pronotal width less than twice its length in the midline. According to De Carlo (1938), B. elongatum has, by contrast, the greatest pronotal width twice its median length (as herein mentioned in the key to B. plebejum , B. micantulum , and B. orbiculatum ), but these measures are suspect, because they appear to be erroneous.

The history of this species is closely linked with that of B. foveolatum . According to Schnack (1976), B. foveolatum differs from B. elongatum by lacking the two dark longitudinal pronotal stripes. Yet B. elongatum specimens studied by De Carlo (1930, 1938) bear two dark longitudinal stripes on the pronotum. However, this structural difference cited by these authors between B. elongatum and B. foveolatum is slight and well within the range of variability found intraspecifically in other species of Belostoma .

Figures

FIGURE 7. Belostoma dentatum (Mayr, 1863) and B. elongatum Montandon, 1908. B. dentatum. 7A–C, Prosternal keel (lateral view): 7A, Specimen from Chaco, Argentina (MACN 5653). 7B, Specimen from Amazonas (INPA 0021059). 7C, Specimen from Rondônia (MZSP). 7D–L, Phallus: 7D–F, Specimen from Chaco (MACN 52437). 7G–I, Specimen from Chaco (MACN 52438). 7J–L, Specimen from Chaco (MACN 50274). B. elongatum. 7M, Prosternal keel (lateral view): specimen from State of Mato Grosso do Sul (DPIC 567). 7N–P, Phallus: specimen from State of Mato Grosso do Sul (DPIC 567). 7D, 7G, 7J, and 7N, Dorsal views. 7E, 7H, 7K, and 7O, Ventral views. 7F, 7I, 7L, and 7P, Lateral views. Scale bar: 1.00 mm.

FIGURE 11. Belostoma candidulum Montandon, 1903, B. horvathi Montandon, 1903, and B. sanctulum Montandon, 1903. B. candidulum. 11A, Prosternal keel (lateral view): specimen from State of São Paulo (SEMC). Scale: 0.50 mm. 11B–D, Phallus: specimen from Chaco, Argentina (MACN 39307). Scale: 1.00 mm. B. horvathi. 11E–F, Prosternal keel (lateral view): 11E, Specimen from State of Minas Gerais (DPIC 1641). 11F, Specimen from State of Minas Gerais (DPIC 1218). 11G–I, Phallus: specimen from State of São Paulo (SEMC 1063). Scale bar: 1.00 mm. B. sanctulum. 11J– K, Prosternal keel (lateral view): 11J, Specimen from State of Espírito Santo (ISNB). 11K, Specimen from State of Rio de Janeiro (DZRJ 17). Scale: 0.50 mm. 11L–N, Phallus: specimen from State of Espírito Santo (ISNB). Scale: 1.00 mm. 11B, 11G and 11L, Dorsal views. 11C, 11H, and 11M, Ventral views. 11D, 11I and 11N, Lateral views. (VED) ventral dilatation.

FIGURE 19. Dorsal habitus. 19A, Belostoma elongatum Montandon, 1908: specimen from State of Mato Grosso (MNRJ 96). 19B, B. foveolatum (Mayr, 1863): specimen from State of São Paulo (MNRJ 85). 19C, B. horvathi Montandon, 1903: specimen from State of Rio de Janeiro (DZRJ 18). 19D, B. micantulum (Stål, 1860): specimen from State of Amazonas (INPA 0021057). Scale bar: 5.00 mm.

FIGURE 23. Geographic distribution map of Belostoma species in southeastern Brazil. 23A, = B. costalimai, = B. cummingsi, = B. dallasi. 23B, = B. dentatum, = B. dilatatum, = B. discretum, = B. elongatum.