Argia tupi Calvert, 1909

Vilela, Diogo Silva, Guillermo-Ferreira, Rhainer, Del-Claro, Kleber & Cordero-Rivera, Adolfo, 2018, Females of two species of Argia from Chapada dos Guimarães National Park, Brazil (Odonata: Coenagrionidae), Zootaxa 4420 (3), pp. 430-438 : 434-437

Description of the female of Argia tupi Calvert, 1909

Figs. 14‒24 , 29b .

Material examined. 2 ♀ (LESTES, Cod. ACR 8184 (described below), ACR 8197), BRAZIL, Mato Grosso, Chapada dos Guimarães National Park, Cachoeira do Marimbondo (15.4330° S, 55.7198° W, 370 m), 0 1 xi 2015, A. Cordero-Rivera leg. [ACR] and R. Guillermo-Ferreira leg. [RGF].

Female ( Fig. 14 ). Head. Labium, labrum, clypeus, base of mandibles, genae, frons and front of head to level of antennae tan, epicranium black, except for small dark cupreous spots lateral to each lateral ocelli and at base of antennae, postocular spots tan, tan occipital bar separated from postocular spots by a thin black line, border of postocular lobes black; eyes (in life) black dorsally and white ventrally; rear of head largely black, a pale line bordering eye margin.

Thorax. Anterior lobe of prothorax tan; middle lobe black with two lateral pale circular spots; propleuron tan, posterior lobe tan, except for rectangular black spot at base, almost separated medially; mesostigmal plate black, mesostigmal lobes strongly erect, almost perpendicular to the mesepisternum, lying somewhat diagonally with medio-apical portion of lobe bent posteriorly ( Figs. 15‒16 ); pterothorax pale with usual pair of black thoracic stripes as follows: mid-dorsal stripe slightly narrower than tan antehumeral stripe, this followed by a broad deeply forked humeral stripe, its upper 0.60 a narrow line along mesopleural suture slightly enlarged at mesopleural pit, posterior arm thicker, extending diagonally to base of wings and connected along crest with mid-dorsal strip, mesinfraepisternum black, pale tan on 0.25 lower portion, remainder of thorax ivory with narrow metapleural stripe ending ventrally at metastigma; venter of the thorax ivory.

Wings. Hyaline, venation black, pterostigma brown; postnodals 16/ 15 in Fw, 14/ 13 in Hw, postquadrangular cells 4/ 4 in Fw and 4/ 4 in Hw, RP2 branching at postnodal 8 in Fw and at postnodal 7 in Hw.

Abdomen. Tan above, ivory below with following areas black: S1 with a dorsal black spot covering basal half; S2 with a dorso-lateral stripe narrowed above medially followed by an expanded portion dorsally but not connecting above, ventrally with an ill-defined black stripe bordering margin; S3‒7 with a similar pattern but middorsal stripe narrower medially and connecting above at apical 0.10 thus isolating a broad tan spindle-shaped dorsal stripe, dorso-lateral stripe apically almost (S3) or (S4‒6) connecting with ventral stripe; S7 with black more expansive thus losing pale spindle-shaped stripe laterally; S8‒9 black apically with a pale blue trident shaped dorsal spot, thicker on S9, S10 mostly pale blue, remainder black; appendages black, ovipositor and styli black, except for white basis of the styli.

Measurements. Fw 28, Hw 27.3, abdomen 32.4, total length 42.

Variations on the specimens examined (n = 2). The other female showed no variations on mesostigmal plates morphology; wing venation showed no variation in postquadrangular cells, RP2 branching or postnodal; size varied as follows: abdomen 31.8‒32.4 (32.1±0.4), total length 41.1‒42 (41.5±0.6), Fw 27.3–28 (27.6±0.4), Hw 26.6–27.3 (26.9±0.4). Body coloration variation for both females is shown in Figs. 17‒24 . The tan and blue coloration were darker in the other female.

Differential diagnosis. In contrast to A. bicellulata , A. tupi is one of the largest Brazilian species occuring within Chapada. Apart from the large body size, A. tupi females can be separated from other Brazilian species, including A. clausseni and A. cyathigera (females yet to be described by Rosser Garrison and Natalia von Ellenrieder) by the morphology of its mesostigmal lobes. In A. tupi the short narrow mesostigmal lobe is strongly erect ( Fig. 16 ), with a less rounded shape when compared to A. claussenii ( Figs. 25‒26 ) and A. cyathigera ( Fig. 27‒28 ). The medio-apical portion of the lobe of A. tupi lies somewhat diagonally in relation to the mesepisternum and is bent posteriorly, whereas in A. claussenii ( Fig. 25 ) and A. ciathygera ( Fig. 27 ) these lobes are not bent posteriorly and have a larger foliate shape.

Habitats and Ecology. This species was collected at a waterfall area in Chapada dos Guimarães National Park ( Fig. 29a ). It inhabits the exposed streams above the waterfall and was found perched on the stones and vegetation around stream margin ( Fig. 29b ). Oviposition was observed in tandem, on the rocky walls of the waterfall, in the roots and other vegetal debris found on the rapid areas of the stream.

Figures

FIGURE 14. Argia tupi (Calvert) BRAZIL: Chapada dos Guimarães; ♀ (ACR 8184).

FIGURES 15‒16. Argia tupi (Calvert) BRAZIL: Serra do Cipó mesostigmal lobes; 15. ♀ dorsal view; 16. ♀ anterior view.

FIGURES 17‒24. Argia tupi (Calvert) BRAZIL: Chapada dos Guimarães; 17. S1‒10, ♀ (ACR 8184); 18. S1‒10, ♀ (ACR 8197); 19. head, ♀ (ACR 8184); 20. head, ♀ (ACR 8197); 21. S8‒10, ♀ (ACR 8184); 22. S8‒10, ♀ (ACR 8197); 23. thorax, ♀ (ACR 8197); 24. thorax, ♀ (ACR 8184).

FIGURE 29 a‒b. Habitats of Argia tupi. 29a. Cachoeira do Marimbondo, natural habitat of Argia tupi; 29b. couple of Argia tupi at its natural habitat.

FIGURES 25‒26. Argia claussenii (Selys) BRAZIL: Serra do Cipó mesostigmal lobes; 25. ♀ dorsal view; 26. ♀ anterior view.

FIGURES 27‒28. Argia cyathigera (Navás) BRAZIL: Nova Teutonia mesostigmal lobes; 27. ♀ dorsal view; 28. ♀ anterior view.