Leptagrion itabaiana Vilela & Lencioni & Santos 2021, sp. nov.

Leptagrion itabaiana sp. nov.

(Figs. 1a, 2 a−b, 3, 4i−j, 6e−f)

Holotype. ♂ (C2256), Brazil, Sergipe, Areia Branca, Serra de Itabaiana National Park, 10.7517 S, 37.3415 W, 179 m asl), 3.ii.2021, J.C. Santos leg. (UFS).

Paratypes. 7♂♂ (C2253, C2254, C2255, C2257, C2258, C2259, C2260), same data as holotype (5♂♂ at UFS, 2♂♂ at FAAL).

Etymology. Named itabaiana (noun in apposition) after the Serra de Itabaiana National Park, Areia Branca municipality, Sergipe state, Brazil, where the new species was collected.

Description of holotype. Head (Figs. 1a, 2 a−b, 6e−f). Labium, labrum, and postclypeus light blue with a black median stripe; base of mandibles and genae pale colored, apex of mandibles black; remainder of head with cupreous metallic reflections, except for two small pale spots lateral to lateral ocelli. Rear of head pale basally, black apically.

Thorax (Figs. 1a, 2 a−b, 6e−f). Anterior lobe of prothorax light blue; medial lobe brown dorsally, light blue laterally; posterior lobe light blue, convex, slightly trilobed, its medial lobe the largest. Pterothorax with a cupreous metallic middorsal carina covering most of mesepisternum; remainder of mesepisternum blue, including mesopleural suture; mesepimeron mostly orange, posteriorly blue; mesinfraepisternum orange anteriorly, light blue posteriorly; metepisternum mostly pale colored, with a thin apical blue stripe, a thin medial orange stripe, and a thin basal blue stripe; remainder of prothorax pale colored. Coxae and trochanter pale colored; legs mostly pale with brown femoral areas.

Wings (Fig. 3). Hyaline; Pt dark brown, rectangular, with pale borders, overlying slightly more than 1 cell in all wings; 8 Px in FW and HW; RP 1 originates at Px 6 in all wings.

Abdomen (Figs. 1a, 2 a−b). S1 dark brown dorsally, pale blue laterally and ventrally; S2 dark brown dorsally, mostly pale laterally, with a blue posterior coloration; S3−6 mostly brown, paler ventrally, with pale basal rings and thick black apical rings; S7 dark brown with a pale basal ring; S−10 brown dorsally, light blue and brown laterally, pale ventrally.

Anal appendages (Figs. 4 i−j). Cerci dark brown, slightly longer than S10; in dorsal view slightly curved inwards, with a medial protuberance; STT beak-like with a sclerotized acute apex; TAT with acute apex, slightly curved inwards; in lateral view cercus with a rounded medial protuberance, ending in a TAT with acute apex. Paraprocts vestigial.

Measurements. FW: 16.6; HW: 16.4; AL: 28.9; TL: 35.9.

Variations in paratypes. Male paratypes do not vary in cercal morphology. Slight differences were observed in thoracic and abdominal coloration, which are probably related to age and/or postmortem differences. Male paratypes varied in size as follows: FW: 16−17, HW: 16−17, AL: 28−30, TL: 35−37.

Female. Unknown.

Differential diagnosis. Leptagrion itabaiana sp. nov. belongs to the group of Leptagrion species possessing cercus with a subterminal tooth (STT) curved medially or slightly cephalad, and possessing or not a terminal apical tooth (TAT), which can have blunt or acute apexes (i.e., L. afonsoi Machado, 2007, L. capixabae Santos, 1965, L. dispar Selys, 1876, and L. elongatum Selys, 1876). Of the aforementioned taxa, the new species is closest to L. afonsoi (Figs. 1b, 4 a−b), and can be separated from this and other congeners by the following character combination (see Table 1 for a comparison with other species): STT of cercus beak-like with a sclerotized acute apex; TAT with acute apex, slightly curved inwards; in lateral view cercus with a rounded medial protuberance, ending in a TAT with acute apex (Figs. 4 i−j).

Habitat and Ecology. Males were found nearby the head office of Serra de Itabaiana National Park (Fig. 5), perching at or flying nearby tank bromeliads of Aechmea aff. marauensis Leme and Aechmea aff. aquilega (Salisb.) Griseb. (Figs. 6 a−f), and also other Aechmea Ruiz & Pav., and Hohenbergia Schult. & Schult. species. At the same locality we also found specimens of L. garbei Santos, 1961 perching at or near bromeliads, where they presented agonistic behaviors against L. itabaiana sp. nov. The type locality is a transition area between two biomes: Caatinga and Atlantic Forest (Silva et al. 2019). Damselflies were found specifically in open areas of white sandy soils called “White Sand” (“Areias Brancas” in Portuguese) that occupy 347 ha, about 0.4 % of the park area (Dantas & Ribeiro 2010). In this type biome many plant species are found such as graminoids (Poaceae and Cyperaceae), shrubs, palms, cacti and bromeliads (Vicente et al., 2005; Silva et al., 2019). The Serra de Itabaiana National Park is a federal conservation unit, and the new species is apparently not threatened by human activities. However, it is important to highlight that the park suffers from the recreational use of trails without park ranger control (Oliveira 2008). The population of L. itabaiana was found adjacent to the main trail, called the “Trilha do Poço das Moças”. In this trail, several anthropic impacts were detected, for instance: damaged plants, clearings, widening of the trail, secondary trails, excessive visitors, noise, unpleasant odor, and garbage (Oliveira 2008).

Final remarks. This is the 18 th Leptagrion species to be described, four years after the last addition to the genus: L. lencioninetoi Lencioni, 2017. Most of Leptagrion species occur in Southern-Southeastern Brazil. Besides L. itabaiana sp. nov., the Leptagrion species recorded so far from the Northeastern region are: L. cyanostigma Machado, 2012, L. dardanoi Santos, 1968, L. dispar Selys, 1876, L. garbei Santos, 1961, L. perlongum Calvert, 1909 and L. siqueirai Santos, 1968 (Lencioni 2006). Our results highlight the importance of preserving fragmented Caatinga and Atlantic Forest areas in the Northeastern region that hold several endemic populations, as well as the importance of encouraging more surveys in Sergipe and other Northeastern states, which may reveal even more species new to science.