Triatoma picturata Usinger, 1939

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 : 356

Triatoma picturata Usinger, 1939

( Fig. 6B )

Triatoma sp. Mazzotti, 1939: 197 .

Triatoma picturata Usinger, 1939: 47 ; Mazzotti, 1940: 98; Islas, 1941: 311; Lent & Wygodzinsky, 1979: 296; Schofield & Galvão, 2009: 92; Monteiro et al., 2018: 284.

Triatoma phyllosoma picturata ; Usinger, 1944: 60; Marcilla et al., 2001: 141; Martínez et al., 2006: 285; Martínez-Hernández et al., 2010: 80.

Meccus picturatus ; Carcavallo et al., 2000: 81; Galvão et al., 2003: 7.

Diagnosis. Male body length 30.5–32.0 mm. Female body length 32.0–33.0 mm. Anteocular region three times as long as postocular region. First antennal segment attaining or shortly surpassing level of apex of clypeus. Overall color of pronotum black, with orange red areas on hind lobe of variable extension; adpressed setae short (0.3 mm). Hemelytra of male attaining hind border of urotergite VII; hemelytra of female not extending beyond basal third of urotergite VII. Overall color of hemelytra black. Corium with orange-red areas, large basal triangular mark, and subapical subquadrate mark; short setae (0.1–0.2 mm). Spongy fossulae of fore and mid tibiae absent in both sexes. Abdomen strongly widened. Overall color of connexival segments black, with posterolateral orange-red markings of variable size, sometimes reaching inner and anterior portion of connexival segments. Pygophore round, as wide as long ( Figs. 8F , 9F ).

Specimens examined. Mexico. 1female ( CAIM), Jalisco, Puerto Vallarta, Brisas del Pacífico , 22 vi 2015 , n/d. 1female ( CAIM), Jalisco, Puerto Vallarta, Colorado, 25 viii 2010 , B.E. 1 male ( CAIM), Jalisco, Puerto Vallarta, Pitillal, 26 v 2011 , n/d. 1 female ( CAIM), Jalisco, Puerto Vallarta, Playa Grande, 29 iv 2011 , n/d. 1 female ( CAIM), Jalisco, Puerto Vallarta, 21 vii 2010 , entomological brigade.

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

Comments. This species is closely related to T. longipennis and T. recurva ( Rengifo-Correa et al. 2021) . Hybrids of T. picturata with T. longipennis and T. pallidipennis are widely expected in the field ( Martínez-Hernández et al. 2010; Rengifo-Correa et al. 2021). Hybrids with T. longipennis are cryptic, exhibiting characters of one or another species, but not a mixture of characters ( Martínez-Ibarra et al. 2008). Morphology of hybrids with T. pallidipennis can be either cryptic or exhibit a mixture of characters of the parental species ( Martínez-Ibarra et al. 2009), for example, they may exhibit the pronotum color of T. picturata and the corium color of T. pallidipennis (Martínez- Ibarra et al. 2009). Triatoma picturata 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). However, the antennal phenotype of non-hybrid specimens presents more cohesion within specimens identified as T. picturata than between these specimens and those classified as T. pallidipennis ( Martínez-Hernández et al. 2010) . The antennal phenotype of T. picturata and T. longipennis is indiscernible ( Martínez-Hernández et al. 2010), but this might be a consequence of their common ancestry. For diagnostic characters, even hybrids retain phenotypic cohesion to just one parent ( Martínez-Ibarra et al. 2008). Specimens of T. picturata , T. pallidipennis , and T. longipennis retain phenotypic identity despite hybridization because their hybrids have lower fitness than their parents ( Martínez-Ibarra et al. 2008, 2015a). Besides, non-hybrid specimens of T. picturata conserve more genetic cohesion with T. longipennis and T. recurva than with T. bassolsae , T. mazzottii , T. pallidipennis , and T. phyllosoma ( Rengifo-Correa et al. 2021) . Then, T. picturata cannot be longer classified as a subspecies of T. phyllosoma and here, we re-establish its species status.

Figures

FIGURE 6. Triatoma spp. A, T. phyllosoma; B, T. picturata; C, T. recurva; D, T. sanguisuga (6D courtesy of C. Dale).

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.