Perilestes jueni, Mendoza-Penagos & Kenzy & Gonçalves & Vilela, 2022

Mendoza-Penagos, Cristian Camilo, Kenzy, Myckey, Gonçalves, Silva & Vilela, Diogo Silva, 2022, Perilestes jueni (Zygoptera: Perilestidae), new species from Amazonas State Northern Brazil, Zootaxa 5219 (6), pp. 576-582 : 577-579

Perilestes jueni sp. nov. Mendoza-Penagos & Vilela

( Figs 1 , 2a )

Holotype. J, Brazil, Amazonas State , São Gabriel da Cachoeira, Ponto 8 (0.165, -67.007, 92 m asl), 2.xii.2021, C.C. Mendoza-Penagos, M. Silva-Gonçalves & S. Da Silva Ribeiro leg.

Etymology. Named jueni (noun in genitive case) after Dr. Leandro Juen, great Brazilian odonatologist, whose tireless work has trained dozens of professionals and made invaluable contributions to our ecological understanding of the Amazonian Odonata fauna.

Description of holotype

Head ( Fig. 1 ). Mouthparts pale, with darkened apex; labrum mostly sky-blue, with a basal dark-brown stripe; anteclypeus sky-blue, postclypeus black; remainder of head black with metallic reflections on frons and vertex; postocular lobes and occipital bar black, with no metallic reflections. Rear of head black.

Thorax ( Fig. 1 ). Prothorax brown dorsally, pale brown laterally; posterior margin of hind lobe nearly straight, with lateral apices slightly bent posteriorly. Humeral stripe of pterothorax thick, black medially, dark brown toward mesopleural suture; a thin white stripe on mesopleural suture; mesepimeron with a dark brown stripe, extending up to mesinfraepisternum; metepisternum white, with a thin basal dark brown stripe; remainder of pterothorax white, with three (one medial and one on each side) ventral dark brown stripes. Procoxae white, meso- and metacoxae white, with an anterodorsal dark brown spot; femora dark brown, paler apically, with a white ring medially; tibiae white, with darkened apical areas; tarsi black.

Wings ( Fig. 1 ). Hyaline, Pt black; Px 10 in FW and 10 in HW; RP 2 arising at Px 6 in Fw and Px 5 in Hw; IR 1 arising distal to pterostigma in both wings; 7 cells behind CuA in FW, 4 in HW.

Abdomen ( Fig. 1 ). S1 with a black dorsoanterior spot, overall coloration light brown dorsally, becoming paler laterally and ventrally; S2 dark brown dorsally, white laterally; S3−7 dorsal and laterally dark brown with a white basal ring and a white spot on each side of apical 3/4; S8 black with a white basal ring and thin basal stripes; S9 black with a thin white basal stripe; S10 black dorsal and laterally, basally white; overall ventral coloration pale brown.

Anal appendages ( Fig. 2a ; right cercus missing). Overall coloration dark brown, with lighter areas on BP, medial lobe of MP and apex of AP; the three portions of cercus subequal in length; BP entire, cylindrical, of uniform width, lacking any lobe or projection; medial lobe of MP forming an entire plate ending in a squared angulation of 90º, with no additional tooth or incision; AP roughly spoon-shaped, with rounded apex.

Measurements (in mm). AL 48.7; TL 57.4; FW 23.2; HW 22.8.

Female. Unknown.

Differential diagnosis. The new species is morphologically close to P. attenuatus , with which it shares the simple morphology of cercus, lacking incisions and additional basal sharp teeth (present in the remaining species of the genus), besides overall body coloration and size. However, a combination of characters of the cerci readily separates P. jueni ( Fig. 2a ) from P. attenuatus ( Fig. 2b , in parentheses): portions of cercus subequal in length (BP the longest portion of cercus), BP of uniform width (BP wide basally, narrower toward apex), MP plate ending in a squared angulation of 90º, with no additional tooth or incision (MP plate rounded, lacking squared angulations, with a small additional posterior globose lobe).

Habitat and Ecology. The holotype was collected in a first-order river inside a terra firme forest with dense vegetation cover ( Fig. 3 ). The forest is used by the Baniwa indigenous community, who carry out some basic subsistence activities within it, such as planting cassava ( Manihot esculenta Crantz ), fruits, and collecting water. However, these activities do not have a severe impact on the environment, which remains otherwise intact. The stream is classified as first order (less than 1 m), black water (according to the classification by Ríos-Villamizar et al. 2013) and with moderate water flow. The stream bottom is mainly sandy with the presence of organic matter. The vegetation is mainly dominated by large trees and small shrubs. Perilestes jueni was perched approximately 1 m high, with wings closed and head up on the tip of a dry branch. This type of pose is common in the representatives of this family, and due to this characteristic, they are difficult to observe in the field. Despite intensive search in the area, only one specimen was found at the site. Other dragonfly species found at this site include Epipleoneura ocuene De Marmels, 1989 , Dimeragrion sp. nov., Heteragrion bariai De Marmels, 1989 , Palaemnema clementia (Selys, 1886) , Psaironeura bifurcata Sj ̂stedt, 1918 and Uracis ovipositrix Calvert, 1909 .

Distribution. So far, the distribution of P. jueni is restricted to a remote area in the municipality of São Gabriel da Cachoeira, Amazonas State, extreme northern Brazil, close to the Colombian-Venezuelan border ( Fig. 4 ).

Figures

FIGURE 1. Perilestes jueni sp. nov. male holotype from Amazonas State, Brazil: left view of habitus.

FIGURE 2. (a) Perilestes jueni sp. nov. male holotype from Amazonas State, Brazil: dorsal view of left cercus; (b) Perilestes attetnuatus Selys, 1886, from Rondônia State, Brazil: dorsal view of cerci.

FIGURE 3. Type location of Perilestes jueni sp. nov. in São Gabriel da Cachoeira, Amazonas State, Brazil.

FIGURE 4. Distributional map of Perilestes jueni sp. nov. and P. attenuatus Selys, 1886, in South America.