Triatoma pallidipennis ( Stål, 1872 )

Rengifo-Correa, Laura, Téllez-Rendón, Juan Luis, Esteban, Lyda, Huerta, Herón & Morrone, Juan J., 2021, The Triatoma phyllosoma species group (Hemiptera: Reduviidae: Triatominae), vectors of Chagas disease: Diagnoses and a key to the species, Zootaxa 5023 (3), pp. 335-365 : 353-354

Triatoma pallidipennis ( Stål, 1872)

( Fig. 5F )

Meccus pallidipennis Stål, 1872: 110 ; Champion, 1899: 210; Carcavallo et al., 2000: 81; Galvão et al., 2003: 7.

Triatoma pallidipennis ; Pinto, 1927: 108; Lent & Wygodzinsky, 1979: 284; Schofield & Galvão, 2009: 91; Monteiro et al., 2018: 284.

Triatoma phyllosoma usingeri Mazzotti, 1943: 81 ; Usinger, 1944: 60.

Triatoma phyllosoma pallidipennis ; Usinger, 1944: 59; Usinger et al., 1966: 310; Marcilla et al., 2001: 141; Martínez et al., 2006: 285; Martínez-Hernández et al., 2010: 80.

Diagnosis. Male body length 31.0–34.0 mm. Female body length 32.0–35.0 mm. Anteocular region three times as long as postocular region. First antennal segment extending beyond level of apex of clypeus. Pronotum black, with short (0.3 mm), strongly decumbent or adpressed setae. Hemelytra of males extending to middle of urotergite VII; hemelytra of females not quite attaining posterior margin of urotergite VI. Membrane of hemelytra and basal half of clavus black. Corium extensively yellowish white, with a basal light orange mark and an apical black triangular mark; short (0.1–0.2 mm) decumbent or adpressed setae. Spongy fossulae of fore and mid tibiae absent in both sexes. Abdomen strongly widened. Connexival segments largely black, with orange-red subtriangular spots on posterior portion. Pygophore round, as wide as long ( Figs. 8D , 9D ).

Specimens examined. Mexico. 1 male ( CAIM), Guerrero, Chilpancingo, Col. Bella Vista , 21 vi 2010 , A. Carreón Soto. 1 male ( CAIM), Guerrero, Eduardo Neri, Zumpango , 28 v 2009 , n/d. 1 female ( CAIM), Jalisco, Autlán , 08 viii 2008 , n/d. 1 female ( CAIM), Guerrero, Taxco de Alarcón, Tecapulco , 22 iv 2010 , U. Entomol. 4. 1 female ( CAIM), Guerrero, Tlapa, Cuadrilla Contlalco , 15 ii 2010 , A. Hdz. Flores. 1 female ( CAIM), Jalisco, Jilotlán de los Dolores, La Calera , 07 vii 2010 , entomological brigade. 1 male ( CAIM), Jalisco, Juchitlán , 24 iii 2009 , n/d. 1 male ( CAIM), Jalisco, Tenamaxtlán , 21 ix 2007 , n/d. 1 female ( CAIM), State of Mexico, Malinalco, Chichicasco , 07 iv 2008 , L. Ochoa. 1 female ( CAIM), State of Mexico, Malinalco , Col. Aldama, 29 iii 2008 , L. Ochoa. 1 male ( CAIM), State of Mexico, Tejupilco, Cañada de Chivas , 28 iv 2008 , n/d. 1 female ( CAIM), State of Mexico, Tejupilco, Carmen de Ixtapa , 24 x 2002 , n/d. 1 male ( CAIM) Michoacán, Churumuco , 20 i 2010 , n/d. 1 male ( CAIM), Michoacán, Taretan , 20 vii 2008 , R. Ponce. 1 male ( CAIM), Michoacán, Tacaltepen, Cerrito de Olivos , 20 i 2010 , n/d. 1 female ( CAIM), Morelos, Cocoyoc , 15 vi 2008 , n/d. 1 female ( CAIM), Morelos, Cuernavaca, Lomas de Ahuatepec, n/d, V. Ochoa. 1 male ( CAIM), Oaxaca, Mariscala , 14 x 2009 , n/d.

Distribution. Mexico: Colima, Guerrero, Jalisco, State of Mexico, Michoacán, Morelos, Nayarit, Puebla, and Zacatecas ( Zárate & Zárate 1985; Galvão et al. 2003). We agree with Zárate and Zárate (1985) that the only historical record of a single specimen in Veracruz state does not represent the true distribution of T. pallidipennis . Wild hybridization between T. pallidipennis , T. longipennis , and T. picturata is recorded in Jalisco and Nayarit ( Martínez-Hernandez et al. 2010).

Comments. This species is closely related to T. bassolsae , T. mazzottii , and T. phyllosoma ( Rengifo-Correa et al. 2021) . Triatoma pallidipennis spatially co-occurs and hybridizes with several species of the T. phyllosoma complex ( T. bassolsae , T. longipennis , T. mazzottiii , and T. picturata ). Hybrids of these species usually exhibit a mixture of characters, but sometimes can be cryptic ( Martínez-Ibarra et al. 2008, 2009, 2011a). Probably, populations of T. pallidipennis from the state of Morelos lack hybrids because this species does not co-occur in the area with other closely related species ( Rengifo-Correa et al. 2021). Hybrids of T. pallidipennis with T. phyllosoma and T. recurva are retrieved in laboratory, but distributions of these species do not overlap ( Rengifo-Correa et al. 2021). Therefore, absence of wild hybrids is probable, but confirmation needs empirical studies. Triatoma pallidipennis was considered a subspecies of T. phyllosoma because of its potential of hybridization and low genetic divergence from other closely related species ( Marcilla et al. 2001; Martínez et al. 2006; Martínez-Ibarra et al. 2008; Martínez- Hernández et al. 2010). Here, we re-establish its valid species status according to phenotypic (morphology and reproductive behavior) and genotypic cohesion evidence (see T. longipennis and T. picturata comments).

Figures

FIGURE 5. Triatoma spp. A, T. longipennis; B, T. mazzottii; C, D, E. T. mexicana. F, T. pallidipennis.

FIGURE 8. Pygophore of Triatoma spp., ventral view (A, T. bassolsae; B, T. longipennis; C, T. mazzottii; D, T. pallidipennis; E, T. phyllosoma; F, T. picturata.

FIGURE 9. Pygophore of Triatoma spp., lateral view A, T. bassolsae; B, T. longipennis; C, T. mazzottii; D, T. pallidipennis; E, T. phyllosoma; F, T. picturata.