Argia carolus 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 : 12-14

Argia carolus Garrison & von Ellenrieder , n. sp.

Figs. 24 (head, thorax, S1– 4 ♂); 47–49 (head, thorax, S1– 4 ♀); 73 (S7– 10 ♂); 96–98 (S7– 10 ♀); 119 (mesostigmal plates ♀); 138 (genital ligula); 158 (appendages ♂); 169 (map); 184 (field picture of ♂); 185 (field picture of ♀); Table 4 (measurements).

Etymology. Named carolus (to be treated as an indeclinable noun) in honor of our friend and colleague Carlos 'Carolus' Esquivel Heredia, in recognition to his valuable contributions to the knowledge of Costa Rican odonates and his kind help and camaraderie during our studies in that country.

Specimens examined. 49 ♂, 7 ♀. Types. Holotype ♂: COSTA RICA , San José Prov.: Reserva Biológica El Rodeo , 7 km W of Villa Colón (9°54' N, 84°16' W, 795 m), 10–13 vii 1990, TWD leg. [ FSCA] . Paratypes: COSTA RICA , Puntarenas Prov. : 1 ♂, La Guaria, 8 km SSW of Santa Elena on road to Interamerican highway, Quebrada Guaria , small side flood channel (10°14'55'' N, 84°50'52'' W, 597 m), 4 viii 2006, WAH & E. Cruz leg. [RWG] ; 1 ♂, Río Cataratas at Pan-American highway (9°5'29'' N, 83°16'14'' W, 160 m), 8 iii 2009, F. C. Sibley leg. [RWG] ; 1 ♂, Golfito, Gamba (8°42'11'' N, 83°11'15'' W, 80 m), ii 2007, S. Schneeweihs & F. Hofhansl leg. [CEH] ; 2 ♂, forest interior W of Gamba (8°42'7'' N, 83°10'47'' W, 200 m), xii 2015, S. Degenhart leg. [RWG] ; 1 ♀, same data but (8°41'2'' N, 83°10'51'' W, 130 m), i 2016, S. Degenhart leg. [RWG] ; 1 ♂, same data but xii 2015 [ CSCA] ; 1 ♂, 1 ♀, same data but (8°41'8'' N, 83°10'48'' W) [SD] ; 3 ♂ same data but [RWG] ; 1 ♂, same data but [ CSCA] ; 3 ♂, same data but (8°42'5'' N, 83°12'46'' W, 115 m) [RWG] ; 1 ♂, same data but [ CSCA] ; 3 ♂, same data but (8°41'16'' N, 83°10'49'' W, 115 m) [RWG] ; 1 ♂, same data but [SD] ; 2 ♂, same data but (8°41'46'' N, 83°12'20'' W, 120 m) [RWG] ; 1 ♂, same data but [SD] ; 1 ♂, same data but (8°40'37'' N, 83°11'59'' W, 110 m) [RWG] ; 1 ♂, same data but (8°40'22'' N, 83°12'6'' W, 100 m) [SD] ; 1 ♂, same data but (8°40'20'' N, 83°11'58'' W, 120 m) [SD] ; 3 ♂ same data but [RWG] ; 1 ♂ same data but [ CSCA] ; 1 ♂, Corcovado National Park , Piedra el Arco (8°34'34'' N, 83°41'42'' W, 20 m), 10–11 iv 1989, Holzenthal & Blahnik leg. [RWG]; Alajuela Prov. : 1 ♂, Río Quebrada Honda, San Mateo {9°56' N, 84°31' W, 290 m}, 6 iii 1987, J. Belle leg. [RWG] ; 1 ♂, Bonnefil Farm, Río Surubres (9°56' N, 84°31' W, 147 m), 16 x 1909, P. P. Calvert leg. [RWG] ; 1 ♂, 1 ♀, same data but [ UMMZ]; San José Prov. : 1 ♂, Hacienda El Rodeo , 7 km W of Ciudad Colón (9°54'49'' N, 84°16'10'' W, 859 m), 17 vii 1990, CEH leg. [CEH] ; 1 ♀, same data but 10–13 vii 1990, TWD leg. [ FSCA] ; 3 ♂, 1 ♀, same data but 28 v 2013, N. von Ellenrieder & RWG leg. [ CSCA] ; 4 ♂, same data but [RWG] ; 1 ♀, 4 km S of Tinamaste, Río Diamantes (9°15'44'' N, 83°46'53'' W, 520 m), 7 iii 2009, F. C. Sibley leg. [RWG] ; 5 ♂, same data but F. C. Sibley leg. [ FSCA] ; 2 ♂, 1 ♀, same data but WAH & F. C. Sibley leg. [RWG]; Cartago Prov. : 1 ♂, Estación de Biología Tropical Río Macho, on trail in secondary forest along Río Juco (9°46'1'' N, 83°51'45'' W, 1,590 m), 13 ix 1990, CEH leg. [CEH].

A medium-sized largely dark species with forcipate male appendages ( Fig. 158 ).

Description of male holotype. Head: entirely black with following parts pale (purple): labrum, base of mandibles, genae, anteclypeus, postfrons, postocular spots and small pale spot anterolateral to lateral ocellus; antennae black, rear of head black except for pale narrow margin bordering eye margin (similar to Fig 24 ).

Prothorax black with following areas pale: anterior lobe, dorsolateral spot on middle lobe, lateral 0.30 of posterior margin of propleuron. Pale areas of pterothorax purple, with broad black middorsal stripe about four times as wide as pale antehumeral stripe, the latter gradually narrowing dorsally to about 0.50 width of base; black humeral stripe extending from anterior 0.80 base of mesinfraepisternum and narrowing above to about 0.50 of basal width, slightly emarginate posteriorly at mesopleural fossa and connecting narrowly below antealar crest with middorsal stripe above and with a short ventrally directed finger on dorsal portion of obsolete interpleural suture; metapleural suture with a narrow elongate black spot at metapleural fossa; posterior carina of metepimeron narrowly rimmed with black; pale colors on side of thorax purple. Wings hyaline with venation black; pterostigma dark brown, surmounting 1.5 cells in all wings; postnodals Fw 17/17, Hw 15/15; postquadrangular cells Fw 4/4, Hw 4/4; RP2 at Fw 8/8, Hw 7/7. Coxae and trochanters black with a wash of brown medially; femora, tibiae, tarsi and armature black.

Abdomen (as in Figs. 24 ; 73; 184) mostly black; S1 with a black basal ring, remainder purple; S2 black with an incomplete pale (purple) dorsal campanulate spot occupying basal 0.60 of segment, laterally black with an indistinct pale lateral stripe; S3 black except for narrow basal ring extended dorsally into a point ending at basal 0.20 of segment; S4 similar to S3 but with only a narrow pale basal ring; S5 with an obscure pale lateral spot basally; S6–8 entirely black; S9–10 blue dorsolaterally and ventrally black; S10 black; torus pale, appendages black.

Genital ligula ( Fig. 138 ), ending in a pair of flexible curved distal flagella strongly arching basally before uniting in a common stem that is partly covered by a broad, quadrate ectal hood ( Fig. 138 a); ental surface of genital ligula distal to flexure smooth ( Fig. 138 c); latero-basal portion of apical segment with an acute sclerotized lobe laterally, its tip ending just before flexure; inner fold present, sclerotized portion proximal to flexure lacking a microspinulate patch on ental surface on each side.

Torus narrow, transversely oval, swollen ventrally, occupying ventral half of torifer and not overlapping bilobed epiproct ( Fig. 158 c); area around epiproct black; epiproct black except for small pale medial lobe and margin of lateral lobes; cercus ( Figs. 158 a, c) about three times longer than wide, narrowing distally abruptly at distal third, extending beyond paraproct, divided apically into a small bluntly triangular lobe and meeting longer linear branch at about a right angle; inner branch long forming slightly inflated capitate glabrous tooth; medial margin slightly concave apically, convex basally, planate dorsomedially; paraproct ( Fig. 158 b) bilobed, its ventral branch subequal to upper branch, ventral branch triangular, its tip acute; upper branch a rounded lobe.

Dimensions. Hw 23.7, abdomen 31.2, total length 39.7.

Description of female paratype ( Costa Rica: San José Prov., 4 km S of Tinamaste, Río Diamantes). Head, pro-, pterothorax and S1–2 as in male ( Fig. 49 ) but pale colors orange brown; black humeral stripe more deeply divided at distal 0.30, the anterior (main) fork narrow and enlarged at mesopleural sulcus; pale dorsal campanulate spot smaller than in holotype; S3 with incomplete narrow pale basal ring; S4–7 entirely black; S8 black with blue distal spot occupying apical 0.50 with narrowing offshoot extending anteriorly to basal 0.30; S9 black with posterior 0.50 blue extending laterally and projecting anteriorly to basal 0.30; S10 blue dorsally, black ventrally, cerci and ovipositor black ( Fig. 98 ).

Mesostigmal lobe as in Fig. 119 , well developed but small, forming a flat, medially directed digit-like lobe elevated above depressed area on mesepisternum and not overlying branch of middorsal carina; base of lobe in dorsal (as in Figs. 119 c, d) and anterior (as in Figs. 119 a, b) views slightly swollen anteriorly, accompanied by a weak transverse carina; distal base of lobe slightly angulate posteriorly, thus setting off lobe from rest of mesostigmal plate; in posterior view (as in Fig. 119 e) lobe thickened externally but lacking a tubercle at juncture with mesepisternum; a small mesepisternal tubercle present at latero-basal margin of mesostigmal lobe.

Variation in paratypes. Variation exists in extent of thoracic and abdominal markings as well as pale color. Fully adult male in life is a dark olive purple which turns almost black in preserved material, even if properly acetoned. Fully adult male often dusted with white pruinosity on sides of thorax especially on metathorax; black humeral stripe in most males as in Fig. 24 but in one male (Hacienda El Rodeo), the stripe is not forked, and it gradually narrows above to about the thickness of the metapleural stripe; another male (Hacienda El Rodeo) similar to that in Fig. 47 . In contrast to male, female varies in pale thoracic coloration from orange brown ( Figs. 47, 49 ) to dark olive green ( Fig. 48 ) to purplish ( Fig. 185 ) as well as development of black humeral stripe. Pale spots on S8– 10 vary in size and reduction as shown in Figs. 96, 97 . Some females lack a carina at anterior base of mesostigmal lobe but distal base of lobe slightly angulate posteriorly thus setting of lobe from rest of mesostigmal plate. Pterostigma surmounting 1–2 cell in males, 1–1.5 in females; postnodals: Fw 14–17, Hw 13–15 in males, Fw 14– 16, Hw 12–14 in females; postquadrangular cells Fw 4, Hw 3–4 in males and females; RP2 at Fw 7–8, Hw 6–7 in males and females. Dimensions. ♂: Hw 22.2 ± 1.11 [20.8–23.9], abdomen 29.8 ± 1.43 [27.6–32.1], total length 38.5 ± 1.8 [35.8–41.5]. ♀: Hw 21.8 ± 2.3 [18.5–24.7], abdomen 26.5 ± 2.3 [23.3–29.3], total length 34.9 ± 3.3 [30.5–38.5].

Diagnosis. Male unique by elongate forcipate shape of cercus ( Fig 158 a). No other species within its range is similar. Argia schneideri ( Fig. 159 ) also has a forcipate cercus but it is longer, extends beyond the level of the paraproct and it lacks the accessory lobe along the distal margin at the distal fourth of the appendage. The genital ligula of A. schneideri ( Fig. 139 ) consists of a long single flagellum instead of the pair present in A. carolus ( Fig. 138 ), and the former species also lacks the large quadrate hood and aciculate recurved lateral lobes present in A. carolus . In the female, the small, mesally directed mesostigmal lobe accompanied by a swollen base and slightly angulate external base is distinctive. The lobe is similar to that of A. schneideri ( Fig. 120 ) but is considerably smaller, about two-thirds the size of that of A. carolus . In both sexes of A. schneideri , the black humeral stripe is not forked or encompasses a small pale isolated spot just below the alar carina ( Figs. 25 , 50 ); in A. carolus , a forked humeral stripe of varying height and condition is usually present ( Figs. 24 , 47–49 ).

Habitat. We collected a few specimens of this dark species at a small, partially shaded, moderately flowing rocky stream at Hacienda El Rodeo on 28 May 2013. Part of the stream was exposed due to clearing of vegetation. Argia carolus was collected at the stream where it entered the shady undisturbed forest. Adults were inconspicuous due to their overall dark color. Other species collected here included Argia anceps , A. cupraurea (one female in tandem with a male of A. oenea ), A. frequentula Calvert , A. oculata Hagen in Selys , A. oenea and A. rogersi Calvert. Haber and Sibley describe the Río Diamantes as a "stream with small and large rocks, about 5 m across". They noted the following for the female: "Tandem at 11:01 with 5909 [male]. Flew up from riffle area with collected mats of dead vegetable debris; apparently ovipositing." At the Río Cataratas, Sibley found this species to be "Fairly common along fast flowing, rocky stream through forest." Specimens were taken at elevations ranging from about 20 m (Parque Nacional Corcovado) to about 1,600 m (Estación de Biología Tropical Río Macho). Flight dates range from March (Río Diamantes) through September (Estación de Biología Tropical Río Macho).

Distribution. Argia carolus seems to be endemic to the Pacific slope of Costa Rica. Its most similar congener, A. schneideri , is clearly allopatric, being restricted as far as known to Ecuador ( Fig. 169 ). We suspect that A. carolus will eventually be found in neighboring Panama.

Figures

FIGURES 24 – 26. Color pattern of male head, thorax, and S 1 – 4 of other species. Head, dorsal view, thorax and S 1 – 4, lateral view.

FIGURES 158 – 160. Male caudal appendages of other species. (a) mediodorsal view; (b) lateral view; (c) dorsal view.

FIGURES 138 – 139. Genital ligula of other species. (a) lateral view; (b) ectal view; (c) entolateral view; (d) detail of field of michrothrichia on distal segment’s base.

FIGURES 47 – 49. 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 119 – 120. 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 184 – 186. Field photographs of other species. (184) A. carolus, male from Quebrada La Guaria, 10 km SSW of Monteverde, Puntarenas Prov., Costa Rica, 4 viii 2006; (185) A. carolus, female from Surubres river, Higuito village, 3.5 km NE of San Mateo, Alajuela Prov., Costa Rica, 7 ix 2008; (186) male of A. rhoadsi from Coy River headwaters, 27 km S of Ciudad Valles, San Luis Potosí State, Mexico, 18 viii 1999. Photograph (184, 185) by WAH; (186) by RWG.

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 169 – 170. Distribution of other species.