Belostoma micantulum ( Stål, 1860 )

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 : 43-46

Belostoma micantulum ( Stål, 1860)

( Figs 12A–E ; 19D )

Zaitha micantula Stål, 1860: 84 .

Zaitha zelotypus White, 1879: 270 .

Belostoma micantulum: Kirkaldy & Torre-Bueno 1909: 191 .

Types.— Belostoma micantulum was described based on a syntype (Rio de Janeiro) deposited in NHRS (see Schnack 1976). Estévez (1996: 71) designated this male specimen syntype as lectotype [not examined].

Material examined.— ARGENTINA. 1 f ( MACN 50264 ): Corrientes, San Cosme , [without date], (Wurth [?]), J. A. de Carlo det. 2 f ( MACN 50331 ): same. * 2 m / 2 f ( MACN 50332 ): Formosa, Palo Santo [?], VI.1941, (Hopper [?]), J. A. de Carlo det. 1 m / 1 f ( MZSP): Salta, Pocitos , I.1959, (A. Martinez), J. R. I. Ribeiro det. 1999. BRAZIL. Amazonas — * 1 m ( INPA 0020959 ): “CUA”, Reserva Duke [?], 20. V.1982, (J. W. Morais), J. R. I. Ribeiro det. 1999. 1 f ( INPA 0020880 ): Igarapé Miratuca , “Parque Nacional Jau”, [01 º 57’ 08” S / 61 º 49’ 19” W], 14–29.VII.1993, ( R. Andreazze, W. Costa, and L. Aquino), J. R. I. Ribeiro det. 1999, [“lençol com luz mista mercúrio, luz negra BL e BLB”]. 1 m ( INPA 0020881 ): same. 1 f ( INPA 0020876 ): Ilha de Marchantaria , 26.III.1976, (I. S. Goraveb [?]), J. R. I. Ribeiro det. 1999. 1 f ( INPA 0020961 ): same, ( Albuquerque ), J. R. I. Ribeiro det. 1999. *1 f ( INPA 0020963 ): same. 1 f ( INPA 0020879 ): Itacoatiara , “Fazenda Aruana-AM 010, km 215”, 25–26.IX.1992, (C. E. Motta, F. A. Peralta, R. S. G. Hutchings, B. R. Teles, and N. Hamada), J. R. I. Ribeiro det. 1999. 1 f ( INPA 0020960 ): Janauacá lake , IX.1976, ([?] Ício), J. R. I. Ribeiro det. 1999. 1 f ( INPA 0021056 ) [“2419”]: Manaus , V.1962, (“vários coletores” [?]), J. R. I. Ribeiro det. 1999. 1 m ( INPA 0021057 ) [“2478”]: same, 05.XI.1962, (“vários coletores” [?]), J. R. I. Ribeiro det. 1999. 1 f ( INPA 0021026 ): same, “ MAO ”, 28.XII.1985, (F. A. Peralta), J. R. I. Ribeiro det. 1999. 1 f ( INPA 0020953 ): “médio Purus ”, 30.VII.1979, (J. Campbell), J. R. I. Ribeiro det. 1999. 1 m ( INPA 0020954 ): same. 1 m ( INPA 0020891 ) [“A342”?]: Negro River, Igarapé Aduja [?], III.1960, (E. J. Fittkau), J. R. I. Ribeiro det. 1999. *1 f ( INPA 0020888 ) [“Sl/Sa 10”?]: Solimões River, Igarapé Grande , 29.IX.1959, ([?] Sioli and [?] Sattler), H. H. Weber det. 1966. 1 m ( INPA 0020889 ) [“Sl/Sa 10”?]: same. Ceará — 1 m ( AMNH): [without a more precise locality and date], (“ Mann and Baker – Stanford Expedition ”), J. R. I. Ribeiro det. 1999. 1 m ( AMNH): Barbalha , V.1969, (M. Alvarenga), J. R. I. Ribeiro det. 1999. Mato Grosso — 3 m / 2 f ( AMNH): Barra do Tapirapé , 26.VII.1963, (B. Malkin), J. R. I. Ribeiro det. 1999. 1 f ( INPA 0020943 ): Bodoquena , XI.1941, (“ Comissão I. O. Cruz ”), J. R. I. Ribeiro det. 1999. 1 m ( INPA 0020975 ): same. * 3 m / 4 f ( AMNH): Porto Velho, Tapirapé River , 18.XII.1962, (B. Malkin), J. R. I. Ribeiro det. 1999. Mato Grosso do Sul — *4 f (DZRJ-a 26): Corumbá, Popular Nova , 06.II.1997, (J. R. I. Ribeiro), J. R. I. Ribeiro det. 1999. Pará — 1 f ( AMNH): Belém- 8 km E, Ananindéua , 01[?]. VI.1973, ( R. T. Schuh), J. R. I. Ribeiro det. 1999, [at light]. * 6 m / 3 f ( AMNH): same, Guamá River , 22.III.1974, ( R. T. Schuh), J. R. I. Ribeiro det. 1999. * 2 m ( AMNH): Jacareacanga , XII.1968, (M. Alvarenga), J. R. I. Ribeiro det. 1999. PARAGUAY. 1 m ( MACN 44197 ): Guairá, Villarrica sic [= Villa Rica], XI.1938, [without collector], J. A. de Carlo det. SURINAM. * 1 m ( MACN): [without a more precise locality, date, and collector], N. Nieser det., J. A. de Carlo det.

Distribution.— ARGENTINA: Buenos Aires ( De Carlo 1930), Chaco ( De Carlo 1930), Corrientes ( De Carlo 1930), Entre Ríos ( De Carlo 1930), Formosa ( Estévez 1996), Itatí ( Schnack 1976), La Plata ( Mayr 1871), Misiones ( De Carlo 1930), Rosário ( Schnack 1976), Salta ( De Carlo 1938), Santa Fe ( De Carlo 1930), Santiago del Estero ( De Carlo 1930), Tucumán ( Estévez 1996). BOLIVIA: Chapare ( Estévez 1996), El Beni [as “Espíritu”] ( Estévez 1996), Santa Cruz ( Estévez 1996). BRAZIL ( Stål 1860): Amapá ( Nieser 1975), Amazonas ( Nieser 1975), Ceará ( Ribeiro 2005), Goiás ( Menke & Lauck 1962), Mato Grosso ( Estévez 1996), Mato Grosso do Sul ( Ribeiro 2005), Minas Gerais ( Nieser & Melo 1997), Pará ( Nieser 1975), Rio de Janeiro ( Mayr 1871), Rio Grande do Sul ( Estévez 1996), Tocantins [as Goiás –Ilha do Bananal] ( Estévez 1996). COLOM- BIA: Amazonas ( Estévez 1996), Cuatro Bocas ( Estévez 1996), Meta ( Roback & Nieser 1974). GUYANA: Alexander Village ( Nieser 1975), Georgetown ( Nieser 1975), Karanambo ( Nieser 1975), West Bank Demerata ( Nieser 1975). PARAGUAY ( De Carlo 1930): Alto [= Altoverá?] ( Estévez 1996), Colonia Fernheim ( Estévez 1996), Emboscada ( Estévez 1996), Primavera ( Estévez 1996), Puerto Guaraní ( De Carlo 1938), Sapucay ( Estévez 1996), Trinidad ( Estévez 1996), Guairá [as “Villarica” sic] ( Estévez 1996). SURINAM: Brokopondo ( Nieser 1975), Commewijne ( Nieser 1975), Coronie ( Nieser 1975), Marowijne ( Nieser 1975), Saramacca ( Nieser 1975), Paramaribo ( Nieser 1975), Republiek ( Nieser 1975), Zanderij ( Nieser 1975). URU- GUAY: Artigas [including Barra de Yucutuja] ( Ruffinelli & Pirán 1959), Arroyo de la Invernada ( Ruffinelli & Pirán 1959). VENEZUELA: Barinas ( Estévez 1996), Caracas ( Estévez 1996), Monagas ( Estévez 1996), San Esteban ( Estévez 1996).

Description.—Measurements (m / f). Total length (from apex of head to apex of hemelytra at rest) 10.4– 13.3 / 11.4–12.4; largest width of body 5.0–6.3 / 5.0–5.8; median length of pronotum 1.85–2.20 / 1.90–2.15; greatest pronotal width 3.75–4.25 / 3.80–4.30.

General coloration dark brown.

Body elliptical. Length of anteoculus 0.85 –0.96 times length of interoculus; length of rostral segment I 0.82–0.95 times length of segment II; anterior frontogenal suture equal to longer than posterior frontogenal suture; clypeus reaching or not reaching ocular line (0–0.03 mm); vertex without longitudinal median carina; posterior interocular width 1.82–2.02 times length of anteoculus, and 1.60–2.00 times width of eye; eyes rounded. Pronotum with longitudinal median carina on its posterior portion; greatest pronotal width 1.93–2.03 times its length; scutellum not reaching nodal line (0.06–0.51 mm), without longitudinal median carina; prosternal keel poorly prominent, rounded, obtuse at apex ( Fig. 12A ). Pilosity not extending along genital operculum, covering about half of connexivum.

Male genitalia ( Fig. 12C ).—Dorsal arms slightly divergent, covering the external margin of ventral diverticulum, rounded at apex in dorsal view; ventral diverticulum strongly curved, with median depression ( MED) on its caudal portion, 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 about 1.1 times its length in ventral view.

Variation.—I have seen a specimen from Corrientes, Argentina which has the prosternal keel more rounded ( Fig. 12B ) than in other specimens.

Notes on biology.—According to Nieser (1975), B. micantulum is a common and eurytopic species, being most often collected at the edges of stagnant waters with vegetation or plant debris. Occasionally it has been found in running water or at places with little or no vegetation or plant debris ( Nieser & Alkins-Koo 1991). Moreover, it does not seem to prefer shade to exposure.

Schnack et al. (1986) stated that this species has a polygamous social system. According to them, polygynous B. micantulum specimens are more abundant than polyandrous ones.

Comparative notes.—As reported in this study, in Nieser (1975), and in Nieser and Alkins-Koo (1991), there is some variation in pronotal size in this species. Forms with pronotal widths less than or considerably more than twice the lengths have been found.

De Carlo (1938) and Nieser and Melo (1997) state that B. micantulum can be distinguished from B. plebejum by the length of body, which is more than 13.0 mm in B. plebejum . Several authors differentiate these two species only on the basis of differences in body length. Interestingly, according to Pereira (1992) and Pereira and Melo (1998), the lengths of adult B. plebejum differed significantly when they were reared exclusively on mosquito larvae or on snails. These differences can bring any B. plebejum specimens within the range of B. micantulum .

Within the B. plebejum group several species may be similar in general shape. The very similar B. plebejum , according to Nieser (1975), has nearly the same genitalia but it seems to be restricted to the central and southern part of South America. Based on Nieser and Melo (1997) and as herein stated, some B. micantulum specimens may be similar to B. plebejum and B. sanctulum (which has been treated as a species of the B. oxyurum group). Yet only the specimens from Minas Gerais agree in several respects with the specimens studied by Stål, Lauck, and Nieser, including the body length ( Menke & Lauck 1962; Nieser & Alkins-Koo 1991; Nieser & Melo 1997). It is possible that several authors apply the name B. micantulum to a complex of species, including B. pygmeum ( Dufour, 1863) and B. denticolle Montandon, 1903 ( Nieser 1975) .

Belostoma sp. [species not yet described, see Estévez (1996) for more details], which may be similar in general shape, has the prosternal keel prominent and the ventral diverticulum of phallus with prominent thickenings along laterodorsal margins ( Estévez 1996). Belostoma lariversi De Carlo, 1960 may be very similar too, but it can be distinguished from B. micantulum by the presence of prominent thickenings along the laterodorsal margins of the ventral diverticulum of the phallus. According to Estévez (1996), B. micantulum can be distinguished from the remaining species of the B. plebejum group by the ventral diverticulum with a median depression on its caudal portion.

Figures

FIGURE 12. Belostoma micantulum (Stål, 1860) and B. plebejum (Stål, 1860). B. micantulum. 12A–B, Prosternal keel (lateral view): 12A, Specimen from Suriname (MACN); 12B, Specimen from Corrientes, Argentina (MACN 50331). Scale: 0.50 mm. 12C–E, Phallus: specimen from State of Pará (AMNH). Scale: 1.00 mm. B. plebejum. 12F, Prosternal keel (lateral view): specimen from State of Bahia (AMNH). 12G–O, Phallus: 12G–I, Specimen from State of Bahia (AMNH). 12J–L, Specimen from State of Minas Gerais (AMNH). 12M–O, Specimen from State of Rio de Janeiro (DZRJ 22). Scale bar: 1.00 mm. 12C, 12G, 12J, and 12M, Dorsal views. 12D, 12H, 12K, and 12N, Ventral views. 12E, 12I, 12L, and 12O, Lateral views. (MED) median depression.

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.