Triatoma mopan Dorn, Justi & Dale, 2018

Dorn, Patricia L., Justi, Silvia A., Dale, Carolina, Stevens, Lori, Galvao, Cleber, Lima-Cordon, Raquel & Monroy, Carlota, 2018, Description of Triatomamopan sp. n. from a cave in Belize (Hemiptera, Reduviidae, Triatominae), ZooKeys 775, pp. 69-95 : 69

Triatoma mopan Dorn, Justi & Dale, 2018 sp. n. Figure 6

Material.

Holotype Male. BELIZE: Cayo: Rio Frio Cave, coordinates: 16.956939/-88.979675, 15 June 2016, Dorn, Justi, Stevens, Monroy, CTIOC, FIOCRUZ. Paratypes. Five males and six females, Cayo: Rio Frio Cave, coordinates: 16.956939/-88.979675, 15 June 2016, Dorn, Justi, Stevens, Monroy (CTIOC; FIOCRUZ [four males and five females]; National Museum of Natural History, Smithsonian Institution [one male and one female])

Diagnosis.

Triatoma mopan has an overall vestiture similar to T. dimidiata , generally with a more slender body. It is believed to have been wrongly identified as T. dimidiata by Lent and Wygodzinsky (1979). Upon close examination, T. mopan can be easily distinguished from T. dimidiata specimens by the consistently pale-yellow hemelytra, and uniformly dark brown to black head and pronotum with scarce pale setae, absent in T. dimidiata . Triatoma mopan has the pronotum with a straight latitudinal depression dividing it in half and the anterior lobe of the pronotum rugose without any distinguishable tubercles (all the examined morphotypes of T. dimidiata present such tubercles) (Figure 3). In addition, the fore-femora with 1+1 apical, small denticles, 2 +1 subapical denticles in both males and females; and mid-femora with 1+1 apical, small denticles, 2 +2 asymmetrical subapical larger denticles on males and 2 +2 larger, asymmetrical subapical denticles on females. In contrast, T. dimidiata presents 1+1 small subapical denticles on both fore- and mid-femora in both sexes (Figure 4). Abdominal spiracles are close or adjacent to the connexival suture and surrounded by spot slightly darker then the tegument in T. mopan , but never adjacent and always surrounded by a well-defined dark spot in T. dimidiata (Figure 5).

Description.

Length of male 26.6-30.1 mm., of female 32.1-38 mm.; width of pronotum of male 6.2-6.3 mm., of female 6-7.4 mm (Table 4). Overall color dark brown or black, with connexivum and corium pale yellow. Pilosity pale yellow, short and scarce (Figure 6).

Head distinctively rugose dorsally (Figure 7), averaging twice as long as width across the eyes (1:0.39-0.46) and slightly longer than the pronotum (1:1.09-1.23). Short, scarce, pale yellow pilosity present in both dorsal and ventral portions (Figure 7). Anteocular region from 2.8 to 3.2 times as long as post ocular (1:0.31-0.35), post ocular region with sides almost straight, subparallel and not rounded. Eyes in lateral view surpassing the level of the ventral surface of the head. Ratio of the width of eye to synthlipsis: 1:1.81-2.46. Ocelli very small, with diameter averaging about half the distance from their anterior border to the posterior margin of the eye. Antenniferous tubercles subcylindrical, situated slightly posterior of middle of anteocular region of head; first antennal segment attaining to the level of or surpassing the apex of clypeus; second segment with many strong setae. Antennal segments presenting a darker to lighter coloration from the first to the fourth segment, going from dark brown (first segment), reddish brown (second segment) to pale yellow (third and fourth segments). Ratio of antennal segments: 1:2.71 –3.4:2.5– 2.6:1.15. Labium slender; first visible segment extending almost to the base of the antenniferous tubercle in males and to the level of apex of antenniferous tubercle in females; second visible segment extending to the anterior portion of the thorax, almost reaching the stridulatory sulcus in males, and attaining level of posterior border of head on females; third visible segment attaining almost to the posterior portion of the stridulatory sulcus in males, and to the anterior half of the stridulatory sulcus on females (Figure 7). Ratio of visible labium segments: 1:1.79 –2.15:0.44– 0.69. Color dark brown (first visible segment) to light reddish brown (third visible segment). Setae pale yellow, with length and density increasing from the first visible through the third visible segment, being the longest and denser on the third segment (Figure 7).

Neck dark, with 1+1 lateral light brown to yellowish spots. Pronotum uniformly dark brown to black, with a distinctive depression forming a straight latitudinal line from the neck to the posterior portion of the pronotum (Figure 8). Anterior lobe rugose, without distinctive tubercles (Figures 3 and 8). Anterolateral angles, short, rounded, in some specimens subconical. Scutellum shallowly rugose, with central median depression heart shaped, apical process about as long as body of scutellum, subcylindrical, slightly downwardly bent at apex. Hemelytra usually surpassing the apex of abdomen but leaving female genital segments exposed. Basal portion of clavus dark brown, apex pale yellow. Corium pale yellow, with the extreme apex black, and with a dark central spot of variable size. Membrane almost as pale as the corium. Legs uniformly dark. Forelegs with 1+1 apical small denticles 2 +1 subapical denticles on both males and females. Middle legs with 1+1 apical small denticles 2 +2 asymmetrical subapical denticles on males and 2 +2 asymmetrical subapical denticles on females (Figure 4).

Abdomen ventrally convex, minutely striate transversally, with scarce yellow pilosity. Mostly dark brown, with yellow spots extending from the connexival suture (Figure 9). Spiracles close or adjacent to connexival suture, usually surrounded by a spot slightly darker than tegument (Figure 9). Connexival segments piceous or black on anterior third to half across entire width, almost always as an extension of the piceous portion of the abdomen, pale posteriorly.

External genitalia dark brown to black, almost round, with setae darker than the rest of the tegument in males; triangular, with long reddish setae on females (Figure 9).

Distribution.

To date, the species is only known from the type locality.

Type-locality.

Rio Frio cave, Cayo District, Belize, coordinates 16.956939/-88.979675.

Etymology.

The specific epithet mopan was chosen to honor the indigenous Mopan people, one of the Mayan groups historically and presently in this area of Belize and Guatemala, and comprises the lineage previously referred to as T. sp. aff. dimidiata (Group 4 - cave; Monteiro et al. 2013, Stevens et al. 2014, Dorn et al. 2016, Justi et al. 2018).

Host-parasite data.

Specimens of T. mopan sp. n. collected prior to its description, in the same Rio Frio cave, were found to be infected with Trypanosoma cruzi (Monroy, unpublished data). The type series was not investigated for parasite infection in order to preserve the integrity of the samples.

Earlier studies completed by our research group, identifying blood sources on specimens of the then undescribed T. mopan collected in the same Rio Frio cave indicate that this species feeds on human, pig, goat or sheep, rat, mouse, duck, bat, opossum, and synanthropic and wild vertebrates ( Stevens et al. 2014).

Bionomics.

Found in caves, in cracks in rocks near water, in humid environment.