Argia cuspidata Garrison & von Ellenrieder, 2018

Garrison, Rosser W. & Ellenrieder, Natalia Von, 2018, Damselflies of the genus Argia (Odonata: Coenagrionidae) from Ecuador with descriptions of five new species, Zootaxa 4470 (1), pp. 1-69 : 12-13

Argia cuspidata Garrison & von Ellenrieder , n. sp.

Figs. 1 (head ♀), 13 (head, thorax, S1– 3 ♂), 24 (head, thorax, S1– 3 ♀), 45 (S1– 3 ♂), 46, 47 (S7– 10 ♂), 60 (S7– 10 ♀), 72 (mesostigmal plates ♀), 106 (appendages ♂), 136 (map)

Etymology. Named cuspidata (L. cuspidata , adj.) in reference to the large ventrally directed blunt cusp-like tooth on the male cercus.

Types. Holotype ♂: ECUADOR, Santo Domingo de los Tsáchilas Prov.: 19 km east of Santo Domingo de los Colorados {0°18'49'' S, 79°1'44'' W, 740 m}, 7 May 1975, A. Langley & J. Cohen leg. [ USNM].

Specimens examined (all paratypes). 8 ♂♂, 1 ♀. ECUADOR, Esmeraldas Prov. : 1 ♂, 1 ♀ (in tandem), seeps 1.1 km NW of Lita at bridge, 5:00 pm {0°53'6'' N, 78°28'32'' W, 470 m}, 2 February 1997, Jerrell J. Daigle leg. [ JJD] ; 2 ♂♂ (1 ♂ in tandem with ♀ of Argia oculata Hagen in Selys ), same data but, seepage pools along RR tracks, 1 km north west of Lita {0°52'57'' N, 78°27'36'' W, 514 m}, 5 February 1997, Jerrell J. Daigle leg. [ RWG] ; 1 ♂, same data but Kenneth J. Tennessen leg. [ RWG] ; 1 ♂, same data but [ FSCA]; Santo Domingo de los Tsáchilas Prov. : 2 ♂♂, 19 km east of Santo Domingo de los Colorados {0°18'49'' S, 79°1'44'' W, 744 m}, 5 July 1975, A. Langley & J. Cohen leg. [ RWG] ; 1 ♂ same data but [ USNM] .

A medium-sized largely dark species with male cercus armed with a blunt anteapical ventral tooth ( Fig. 106 ) and unmodified mesostigmal lobe in the female ( Fig. 72 ).

Description of male holotype. Head: labrum, base of mandibles, genae and frons entirely pale (ivory green), anteclypeus brown, postclypeus dark brown with a well-defined medial pale spot, epicranium black with small pale spot anterolateral to lateral ocellus, large violaceous postocular spot laterally confluent with eye, occipital bar black (as in Fig. 13 ), dorsal surface of postocular lobe black; antennae black, rear of head mostly black with broad lateral margin bordering eye ivory.

Prothorax black with following areas pale: obscure pale rim on anterior lobe, dorsolateral spot on middle lobe confluent posterolaterally with pale propleuron, lateral third of hind lobe of prothorax. Pale areas of synthorax purple laterally, olive dorsally, with broad black middorsal stripe about twice as wide as olive antehumeral stripe, the latter slightly narrowing dorsally; broad black parallel humeral stripe (as in Fig. 13 ) extending from base of mesinfraepisternum and connecting below antealar crest with middorsal stripe above and with dorsal portion of obsolete interpleural suture; metapleural stripe narrow; pale colors on side of thorax purple.

Wings hyaline with venation black; pterostigma dark brown, surmounting 1 cell in all wings; postnodals Fw 11/12, Hw 10/11; postquadrangular cells Fw 3/3, Hw 3/3; RP 2 at Fw 6/5.5, Hw 4/4. Coxae and trochanters pale except for black on ventral and anterior portions of coxae and dorsum of trochanters; base of metafemora and external surface of tibiae pale, tarsi and armature black.

Abdomen (as in Figs. 45, 46) mostly black; S1 with a black basal ring, remainder purple; S2 violaceous with a lateral black stripe interrupted medially with latter part extending to apical fourth of segment, broadening dorsally with a narrow dorsal offshoot thus restricting pale dorsum of segment; S3 black with a pale basal ring and a broad parallel pale dorsal stripe extending to and abruptly ending at apical 0.5 of segment, a vestigial obscure pale ventrolateral stripe at along medial half of segment; S4–7 similar to S3 but entirely black dorsally and with medial pale stripe longer and paler thus giving the appearance of a dark, pale, dark pattern when viewed laterally; S8 black with an elongate pale (purple) spot, about twice as high posteriorly as basally and anteriorly almost connecting with incomplete dorsal pale basal ring; S9 black laterally with a large pale spot dorsally, apical fourth black dorsally; S10 black; torus pale, appendages black.

Genital ligula as in A. acridens (as in Fig. 89 ), lacking microspinulate patch on ental surface proximal to flexure on sclerotized area; distal segment largely membranous armed basally with a curved sclerotized flagellum. Torus small, oval, swollen, occupying outer half of torifer ( Fig. 106a ); area around epiproct and base of same black; cercus ( Fig. 106b ) slightly surpassing paraproct, slightly longer than wide, swollen basally with medial basal margin linear and carinate narrowing distally and armed with a large ventrally directed subapical tooth whose tip is bluntly rounded ( Figs. 106a, c, e ); paraproct unilobate, almost quadrate in lateral view with a small tuberculate tip ( Figs. 106b, c ).

Dimensions. Hw 19.5, abdomen 27.2, total length 34.8.

Description of female paratype ( Ecuador: Esmeraldas Prov., seeps 1.1 km northwest of Lita at bridge, collected in tandem with male).

Head ( Fig. 1 ), pro- and synthorax and S1, 2 as in male ( Fig. 24 ), but pale areas light brown and more extensive and dark humeral stripe parallel, as black as middorsal stripe; S1 as in male; S3 tan dorsally, with a elongate lateral black stripe with apical 0.20 enlarged and sending a dorsal offshoot thus constricting pale dorsal stripe above followed ventrally by an irregular pale lateral stripe and margined ventrally by black; S4 entirely black with following areas pale: a complete irregular pale basal ring connecting with a thin pale middorsal stripe that extends to apical 0.2 of segment, and an elongate pale ventrolateral spot along medial half of segment thus giving the appearance of a dark, pale, dark pattern when viewed laterally; S4–7 similar to S3; S8 black with pale light olive green spot dorsally and laterally, this spot constricted laterally by black and posteriorly by black apical ring; S9 black except for small ill-defined pale lateral spot at apical third; S10 black; ovipositor black with dorsoapical margin brown, cercus black (Fig. 60).

Mesostigmal lobe lacking, area immediately behind obsolete posterior margin of mesostigmal plate with a slight depression ( Fig. 72 ) medial arm of mesostigmal plate prominent, glabrous.

Variation in paratypes. Little variation was observed in the paratype series. The pale lateral spot on S 8 in male can range from moderately large as in holotype (Fig. 46) to very small (Fig. 47). Pterostigma surmounting 1 cell in males (N=9), 1 in female (N =1); postnodals: Fw 11–14 in males, 12 in female, Hw 10–12 in males, 10 in female; postquadrangular cells Fw 3, Hw 3 in males, Fw 3, Hw 3 in female; RP 2 at Fw 5–7, Hw 4–6 in males, Fw 5, Hw 4 in female. Dimensions. ♂: Hw 19.3 ± 0.5 [18.6–20.2], abdomen 27.5 ± 0.6 [26.4–28.3], total length 35.1 ± 0.8 [33.9–36.5]; ♀: Hw 20.5, abdomen 25.2, total length 32.8.

Diagnosis. This species is similar to the sympatric A. acridens and is diagnosed under that species.

Remarks. A male of A. cuspidata from the same locality as the female described above as A. cuspidata was collected in tandem with a female of another species. That pair, collected by J. Daigle, presented a problem as to which of these two females, the one described above, or the one in tandem, represented the true female of A. cuspidata . Close examination of the latter female mesostigmal plates and body markings matched those for A. oculata and some males of that species were collected at the same locality. We are, therefore, fairly certain that the single female described above truly represents the female of A. cuspidata .

Habitat. Apparently confined to seepages associated with larger rivers and creeks.

Distribution. As far as known endemic to Ecuador, restricted to Esmeraldas and Santo Domingo de los Tsáchilas Provinces west of the Andes ( Fig. 136 ).

Figures

FIGURES 1–8. Color pattern of head. Head, anterior view (1); head posterior view (2–5); labrum, anterior view (6–8).

FIGURES 103–106. Male caudal appendages. (a) lateral view; (b) dorsal view; (c) mediodorsal view; (d) posterior view; (e) ventral view.

FIGURES 69–72. Female mesostigmal plates. (a) dorsal view; (b) detail of mesostigmal lobe, dorsal view; (c) frontal (anterior) view; (d) detail of mesostigmal lobe, posterodorsal view (on edge).

FIGURES 9–13. Color pattern of male head, thorax, and S1–4. Head, dorsal view, thorax and S1–4, lateral view.

FIGURES 89–93. Genital ligula. (a) lateral view; (b) ectal view; (c) entolateral view.

FIGURES 23–27. Color pattern of female. Head, thorax, and S1–4 (23, 24, 26, 27); pterothorax (25). Head, dorsal view, thorax and S1–4, lateral view.

FIGURES 136–137. Distribution of new Argia species and closest congeners in Ecuador.