Argia schorri Garrison & von Ellenrieder

Garrison, Rosser W. & Ellenrieder, Natalia Von, 2017, New species of the damselfly genus Argia from Mexico, Central America and Ecuador with an emphasis on Costa Rica (Insecta: Odonata: Coenagrionidae), Zootaxa 4235 (1), pp. 1-93 : 27-29

Argia schorri Garrison & von Ellenrieder , n. sp.

Figs. 28 (head, thorax, S1– 3 ♂); 51 (head, thorax, S1– 3 ♀); 77 (S7– 10 ♂); 100 (S7– 10 ♀), 101 (S1–5); 121 (mesostigmal plates ♀); 125 (wings); 142 (genital ligula); 162 (appendages ♂); 170 (map); 190 (field picture of ♀); Table 4 (measurements).

Etymology. Named schorri (Latinized name) in honor of our friend and colleague Martin Schorr, in recognition of his contributions to our knowledge of Odonata through the establishment of the International Dragonfly Fund, which has supported the research of countless odonatologists worldwide, his compilation of the Odonatological Abstract Service, and editing of the IDF-Reports for the past twenty years.

Specimens examined. 6 ♂, 1 ♀. Types . Holotype ♂: COSTA RICA , Puntarenas Prov.: 2.8 miles E of Golfito {8°39' N, 83°7 W, 35 m}, 4 vii 1967, O. S. Flint, Jr. & M. A. Ortiz B. leg. [ USNM] . Paratypes: COSTA RICA , Puntarenas Prov.: 1 ♂, same data as holotype [ USNM] ; 1 ♂ same data as holotype but [RWG] ; 1 ♂ same data as holotype but [ CSCA] ; 1 ♂, same data as holotype but [ USNM] ; 2 ♂, 1 ♀, 2 km NE of Uvita, Finca Carolina, Uvita Tropical Studies Institute, Río Ballena and small tributaries in primary and secondary forest (9°9'47'' N, 83°42'49'' W, 275 m), 15 xi 2010, W. Haber leg. [RWG].

A dark medium-sized species similar in male appendage morphology ( Fig. 162 ) to A. popoluca ( Figs. 163, 164 ).

Description of male holotype (colors poorly preserved). Head: Labium pale merging to black at basal half, ante- and postclypeus black, genae and base of mandibles pale, ante- and postfrons and anterior portion of scape pale, remainder of head black with purple postocular spots and small pale spot anterolateral to lateral ocellus; remainder of antennae black, rear of head black except for broad margin bordering eye.

Prothorax black with following areas pale: anterior lobe, dorsolateral spot on middle lobe, propleuron except for notopleural suture. Pale areas of pterothorax dark purple, with black middorsal stripe about as wide as pale antehumeral stripe, the latter gradually narrowing dorsally; black humeral stripe extending from base of mesinfraepisternum and connecting narrowly below antealar crest with middorsal stripe above and encompassing a small pale spot just below carina (similar to Fig. 28 ); interpleural suture with narrow black stripe separating paler areas on side of thorax (as in Fig. 28 ). Wings hyaline with venation black; pterostigma short, black, surmounting 1 cell in all wings (as in Fig. 125 ); postnodals Fw 12/12, Hw 11/11; postquadrangular cells Fw 3/3, Hw 3/3; RP2 at Fw 7/7, Hw 5/5. Coxae and trochanters pale washed with black anterior portions of coxae; femora, tibiae, tarsi and armature black.

Abdomen (as in Figs. 28 , 77 ) mostly black; S1 with a black basal ring, remainder purple; S1 blue with a narrow irregular black ring basally; S2 pale (purple) above with an irregular black lateral stripe ending just before black annulus, its anterior end connecting as a narrow black ring above, at apical 0.20 sending a narrow triangular offshoot dorsally but connecting above, ventrally with irregular pale stripe; S3–4 black laterally with pale basal ring and middorsal stripe ending at apical 0.20; S5–7 black with incomplete pale basal ring; S8–10 blue dorsally, black laterally (as in Fig. 77 ); torus pale, appendages black.

Genital ligula ( Fig. 142 ) consisting of a long ridged flagellum, with a pair of entolaterally directed quadrate lobes at base.

Torus small, confined to ventral margin of torifer, the latter slightly triangularly concave, its base approximate to the opposite, and both completely overlapping bilobed epiproct ( Fig. 162 a, c); cercus ( Fig. 162 a, c) about twice as long as wide, rectangular, about subequal to paraproct, its tip slightly concave with a small partially hidden recurved tooth on medioapical margin; paraproct bilobed, its ventral branch much smaller than broadly triangular anteriorly directed dorsal branch ( Fig. 162 a, b).

Dimensions. Hw 19.4, abdomen 27, total length 34.4.

Description of female paratype ( Costa Rica: Puntarenas Prov., 2 km NE of Uvita, Finca Carolina, Uvita Tropical Studies Institute, Fig. 190 ). Head similar to male but postocular spot not confluent to eye ( Fig. 51 ); pro- and pterothorax and S1 as in male but antehumeral stripe brown and pale areas of pterothorax pale green ( Fig. 51 ); S2 similar to male but with campanulate spot extending to apical 0.40; S3 with a blue basal ring and narrow blue middorsal stripe, apical 0.30 and laterally except for medial pale streak black ( Figs. 51 , 101 ); S4 similar but pale middorsal stripe narrower and pale mediolateral streak reduced; S5–7 black except for pale basal ring; S8 blue dorsally, black laterally; S9 narrowly blue dorsally with an offshoot of blue extending cephalad to medial 0.50, remainder black; S10 and ovipositor black ( Fig. 100 ).

Mesostigmal lobe small, forming a raised recurved planar lobe arising laterally on lateral branch of carina just posterior to medial border of mesostigmal plate ( Fig. 121 d, c); lobe thickened when viewed posteriorly ( Fig. 121 e); a prominent mesepisternal tubercle medioposteriorly to mesostigmal lobe ( Fig. 121 b, c, e).

Variation in paratypes. Little variation was observed in the paratype series. The metapleural stripe in two males (2 km NE of Uvita, Fig. 28 ) is about 0.70 as thick as the humeral stripe. Pterostigma surmounting 1 cell in males and female; postnodals: Fw 12–14 in males, 13 in female, Hw 10–11 in males, 10 in female; postquadrangular cells Fw 3–5, Hw 3 in males, Fw 3, Hw 3 in female; RP2 at Fw 6–8, Hw 5 in males, Fw 6–7, Hw 4 in female. Dimensions. ♂: Hw 18.8 ± 0.90 [17.6–20.3], abdomen 25.5 ± 1.11 [24–27], total length 32.7 ± 1.27 [31.1–34.2]; ♀: Hw 20.1, abdomen 25.3, total length 32.8.

Diagnosis. Species unique in the male by diminutive rim-like torus and adjacent torifer completely overlapping epiproct ( Fig. 162 a, c), and in the female by the placement of recurved mesostigmal lobe on lateral branch of middorsal carina. In addition, the genital ligula consisting of a long, ridged single flagellum and a pair of entolaterally directed quadrate lobes at base ( Fig. 142 ) and the shortened pterostigma covering only one cell ( Fig. 125 ) will easily serve to distinguish this species. The male appendages of A. schorri ( Fig. 162 ) are superficially similar to those of A. popoluca ( Figs. 163, 164 ), as well as its color pattern ( Figs. 129 ; 188, 189). However, A. popoluca differs from A. schorri by its male tori broadly ovate, occupying the ventral half of the torifer and not overlapping the epiproct ( Figs. 163 a, c, 164a, c) and by its two long flagella united basally by a common stem, broadened laminate base and lack of a pair of entolaterally directed quadrate lobes at base of genital ligula ( Figs. 143, 144 ). In the field, male A. popoluca have smaller postocular spots that are not confluent with the eye, and the pale middorsal stripes are more extensive, often attaining the apical 0.20 of S6 ( Figs. 188, 189 ). In the female, the mesostigmal lobes occupy the medial 0.50 of the hind margin of the mesostigmal plate, and are large broadly upright foliate structures that are almost approximate. Most females of A. popoluca have mesostigmal lobes as shown in Fig. 123 , but one female ( Costa Rica: Braulio Carrillo National Park) has a strongly recurved lobe medially ( Fig. 122 c, d, e). It was collected with a male the appendages of which are typical for this species.

Argia popoluca is apparently a variable species. Calvert (1902) in his original description mentions four postquadrangular cells in the Fw, and most material we have examined from Mexico sustains Calvert’s observation. Specimens from farther south generally have only three Fw postquadrangular cells. The extent of the middorsal blue stripe is also variable, extending for most of the dorsum on S3 variably through S7 ( Figs. 188, 189 )1.

Remarks. The small series (including holotype) of four males from Golfito was apparently exposed to 1. Garrison et al. (2003) examined the syntypes of Argia variata Navás, 1935 , stating that “… A. variata is a bona fide species in the [A.] gerhardi [ Calvert, 1909]/ nigrior [ Calvert, 1909] group.” Further examination of specimens of A. popoluca from over its entire range show that South American material previously referable to A. variata do not significantly differ from Central American material currently going under the name of A. popoluca . The genital ligula morphology of A. variata is the same as for Central American specimens, and all specimens differ from species (including type material) previously included within the A. gerhardi / kokama / nigrior complex. Correspondingly, we consider Argia variata Navás, 1935 , to be a junior synonym of A. popoluca Calvert, 1902 .

excessive heat, causing the wing membrane and entire body to become excessively shiny and the colors poorly preserved.

Habitat. Small trickles within primary and secondary forests. On 31 May 2013, we attempted to locate this species at its type locality (2.8 mi E of Golfito) but were unsuccessful, probably due to overcast weather and intermittent precipitation. The area consisted of a small shaded stream within shaded forest, and no Odonata were seen. Specimens have been collected at elevations ranging from about 35 m (2.8 mi E of Golfito) to 275 m (2 km NE of Uvita), ranging from July (2.8 mi E of Golfito) to November (2 km NE of Uvita). Haber noted the following for two males and female collected at Finca Carolina: "[male & female] Perched on shrubs in sunny spot on high bank of tiny trickle down steep hillside" and [male taken in] "Light gap on high bank of tiny forest trickle down steep hillside".

Distribution. Known so far only from the southern Pacific side of Costa Rica, where it is sympatric with its similar-looking congener A. popoluca ( Fig. 170 ).

Figures

FIGURES 27 – 29. Color pattern of male head, thorax, and S 1 – 4 of other species. Head, dorsal view, thorax and S 1 – 4, lateral view.

FIGURES 161 – 164. Male caudal appendages of other species. (a) mediodorsal view; (b) lateral view; (c) dorsal view; (d) right cercus, ventral view.

FIGURES 124 – 125. Male wings, right pair.

FIGURES 73 – 79. Color pattern of male S 7 – 10 of other species, lateral view.

FIGURES 142 – 144. Genital ligula of other species. (a) lateral view; (b) ectal view; (c) entolateral view.

FIGURES 187 – 190. Field photographs of other species. (187) A. rhoadsi, pair in copula from forest stream at McAllen Nature Center, Texas State, USA, 12 xi 2005; (188) A. popoluca, male at road into Arenal Observatory Lodge, Alajuela prov., Costa Rica, 4 vi 2015; (189) male of A. popoluca from El Remanso, NW of Cabo Matapalo and 22 km by road S of Puerto Jimenez, Puntarenas Prov., Costa Rica, 23 i 2005; (190) female of A. schorri at La Gamba Biological Station, 8 km NW of Golfito, Puntarenas Prov., Costa Rica, 11 ix 2011. Photograph (187, 189) by DRP; (188) by N. Smith; (190) by WAH.

FIGURES 50 – 52. Color pattern of female head, thorax, and S 1 – 4 of other species. Head, dorsal view, thorax and S 1 – 4, lateral view.

FIGURES 96 – 102. Color pattern of female S 7 – 10 of other species, lateral view (93 – 100, 102); S 1 – 5, dorsolateral view (101).

FIGURES 121 – 123. Female mesostigmal plates of other species. (a) frontal (anterior) view; (b) detail of left mesostigmal lobe, frontal view; (c) dorsal view; (d) detail of left mesostigmal lobe, dorsal view; (e) detail of right mesostigmal lobe, posterior view.

FIGURES 129 – 131. Genital ligula of metallic species. (a) lateral view; (b) ectal view; (c) entolateral view.

FIGURES 169 – 170. Distribution of other species.