Thraulodes panamensis, Kluge, Nikita J., 2020

Kluge, Nikita J., 2020, Systematic position of Thraulodes Ulmer 1920 (Ephemeroptera: Leptophlebiidae) and descriptions of new and little-known species, Zootaxa 4756 (1), pp. 1-142 : 44-50

4. Thraulodes panamensis sp. n.

( Figs 122–150 )

Etymology. At present this species is known only from Panama.

Material examined. Holotype: L-S-I ♂ {specimen [ XVI] (7) 2018}, PANAMA, Provincia Bocas del Toro, Punta de Peña, Rio Guabo (8°55’N, 82°11’W), 30.I.2018, coll. N. Kluge & L. Sheyko. Paratypes: the same locality and collectors, 29–31.I.2018: 1 L-S-I ♂, 2 L /S ♂, 1 L-S-I ♀; Provincia de Colon, Parque Nacional Soberania, Rio Fri- joles, camina del oleoducto, 10.II.2018, coll. N. Kluge & L. Sheyko: 2 L-S-I ♀, 3 S-I ♂, 1 S-I ♀, 39 larvae; Provincia Chiriqui, E. of Caldera, 19.XII.1977, coll., R. W. Flowers: 2 I ♂, 2 I ♀.

Descriptions. Larva. CUTICULAR COLORATION ( Figs 122–127 ). Dorsal side of head, thorax and abdomen mostly brown with few blanks: pronotum bordered by light laterally, with or without other blanks; fore protoptera with convex and concave longitudinal veins lighter than background; abdominal terga with blanks on lateral parts, area mediad of tergalii attachments nearly unicolor brown. Femora mostly brown, with blanks; tibiae and tarsi uniformly light brown.

HYPODERMAL COLORATION ( Fig. 128 ). Abdominal terga, besides cuticular coloration (see above) often with paired transverse or round blackish spots corresponding to midway gray spots of imago. Tergalii brown or gray, tracheae black ( Fig. 129 ).

SHAPE AND SETATION. Clypeus widened distally; labrum 1.3–1.4 times wider than clypeus ( Fig. 123 ). Labrum widest at 1/3 of length from base; initial fore margin (turned ventrally) without median emargination, with all 5 denticles wide; anterior transverse setal row regular, as wide as 3 denticles (as in Fig. 88 ). Maxilla with 16–17 pectinate setae in apical-ventral row.

Femora: Stout setae on anterior surface widened distally, apically rounded ( Fig. 130 ). Irregular row of hairs near inner margin absent on fore femur, present on middle and hind femora.

Fore tibia ( Fig. 131 ): outer hairs form two irregular rows; inner-anterior row of recurved hairs absent; inneranterior row of stout setae absent; inner field of stout pointed setae moderately dense (setae lengths subequal to distances between them), its setae subequal in lengths, forming 2 rows (setae of anterior row partly dentate, setae of posterior row smooth).

Hind tibia ( Fig. 132 ): outer-anterior row of stout setae consists of two clearly different types of stout setae: numerous very short truncated ones and several long spoon-like ones; outer-posterior row of stout setae consists of blunt stout setae of various lengths; posterior hairs located between these rows, numerous and form more than one row (besides row of hairs posteriad of outer-posterior row of stout setae); stout setae of inner-anterior row short, widened distally and blunt.

Claws with 6–9 denticles on rigid portion, with or without minute denticles on articulatory portion.

Tergalii ( Fig. 129 ): each lamella slender, tracheae without side branches.

Male genitalia in last larval instar ( Fig. 147 ): protogonostyli short and separated one from another by shallow emargination. Each protopenis lobe with small, sharply projected gonopore-bearing process bent laterally; gonopores opened caudally-laterally.

Subimago ( Figs 137–138 , 146 ). CUTICULAR COLORATION. Cuticle mostly colorless, with brown areas. Flagellum of antenna brown. Pronotum colorless. Mesonotum mostly colorless, with contrasting dark brown antelateroparapsidal and lateroparapsidal sutures, brown anteronotal transverse impression and chromozone of medioscutum; chromozone of submedioscutum either nearly colorless ( Fig. 137 ), or light brownish, contrastingly lighter than chromozone of medioscutum ( Fig. 138 ). Thoracic pleura and sterna colorless. On each leg femur entirely colorless, tibia and tarsus brown. Cuticle of wings colorless, microtrichia light brownish. Abdominal terga, sterna and gonostyli colorless, caudalii brown.

TEXTURE. On tarsi of all legs, 1st tarsomere with microtrichia (as tibia), 2nd–5th tarsomeres coved by blunt microlepides; pointed microlepides present near apical margins of 2nd–4th tarsomeres of middle and hind legs (as in Fig. 473 ).

Male imago ( Figs 133–136, 140–142 , 143–145, 148 ). Head brown. Antenna with scapus ocher, pedicellus brown, flagellum ocher. Dorsal eyes contiguous medially, dull orange.

Prothorax whitish with pair of dark brown spots above coxa. Mesoscutum ocher with brown, scutellum whitish. Metanotum and lateral sides of pterothorax ocher with brown. Ventral side of pterothorax with mesothoracic episterna, furcasternal protuberances and furcasternal median impression dark brown, basisternum and other areas whitish ( Fig. 135 ).

Cuticle of legs mostly colorless; on fore leg apex of femur and base of tibia with cuticle light brownish. Legs with following hypodermal pigmentation on whitish background: Fore femur with triangular brown spot on anterior side at 1/4 from base and with multicolored apical band occupying distal 0.4 of femur; apical band orange, proximally and apically narrowly bordered by blackish-brown, on inner and outer sides with blackish-brown longitudinal stripes. Fore tibia with dark brown spots on base and on apex. Middle and hind femora with multicolored pre-apical band within apical 0.4 of femur; pre-apical band mainly orange-brown, proximally bordered by blackish-brown, on inner and outer sides with blackish-brown longitudinal stripes; apical 0.1 of femur non-pigmented. In holotype, relation of fore femur to fore wing length 60:270; proportions femur/tibia/tarsomeres on fore leg 60:90:2:21:14:9:6; on middle leg 60:68:2:4:3:2:6; on hind leg 71:77:2:4:3:2:6.

Fore and hind wings with dark brown macula on costal brace and bases of Sc and R; longitudinal and cross veins colorless (proximal coloration of fore and hind wings appears during larval development and present both in subimago and imago). Costal cross veins proximad of bulla few, colorless and very thin, so that visible only under high magnification ( Fig. 142 ). Pterostigmatic cross veins moderately dense, oblique, arched, non-branched ( Fig. 133 ). Hind wing with prominent or blunt costal projection ( Fig. 148 ).

Abdominal hypodermal coloration: Tergum I brown. Terga II–VI whitish, translucent; terga III–VI with pair of small gray midway spots; pleura with blackish stigmatic dots. Tergum VII orange, tergum VIII anteriorly-medially orange and posteriorly-laterally white, terga XI–X orange. Sterna I–IX whitish. Caudalii with segments alternated as following: black; white; white with base black; white.

Genitalia ( Figs 140–141 , 143–146 ): Styliger and gonostyli whitish. Dorsal extension of styliger narrow and prominent. Penis lobes relatively long, moderately widened and divergent apically, with narrow lateral pouches. Apico-lateral area forming ear, projected laterally-caudally. Telopenes in form of spear-like rolls, attached on dorsal side and directed medially-dorsally, nearly straight, with groove opened dorsally-laterally ( Fig. 144 ).

Female imago ( Fig. 139 ). Pronotum medially brown with ocher, laterally whitish; abdominal terga II–VI brownish with ocher; in other respects coloration similar to that of male.

Eggs ( Figs 149–150 ). Mostly barrel-shaped. Each KTC surrounded by thick ring-like cove. Other chorion with evenly dispersed protuberances.

Dimension. Fore wing length (and approximate body length) 6.5–7 mm.

Comparison. Male imago of Th. panamensis sp. n. has genital structure, coloration of thorax, wings and abdomen the same as in Th. bolivianus Dominguez 1986 described from Bolivia and Th. insular Domínguez et al. 2015 described by Zúñiga et al. (2015) from Gorgona Island in Colombia.

Th. panamensis sp. n. differs from Th. bolivianus by the coloration of the fore femur: proximad of the multicolored apical band, Th. panamensis sp. n. has a small spot ( Fig. 134 ), while Th. bolivianus has a wide band reaching the multicolored apical band: «una banda amplia, que ocupa el 1/3 medio y que toca la banda apical, también grisnegruzca» ( Domínguez 1986: 150).

Th. panamensis sp. n. differs from Th. insular by the absence of a black spot on proximal part of middle and hind femora ( Th. panamensis sp. n. has such a spot on fore femur only) and by orange color of the dorsal eyes (while in Th. insular the dorsal eyes are gray).

Th. panamensis sp. n. is similar to Th. centralis Traver 1946 by structure of genitalia; it differs by the white background of legs in imago and subimago (instead of yellowish orange in subimago of Th. centralis ), by the abdominal tergum VII darker than VIII (instead of lighter in Th. centralis ) and by white abdominal sterna (while in Th. centralis sterna VII-IX are dark red-brown).

Imagines of Th. panamensis sp. n. differ from other examined species by white scutellum.

Egg structure of Th. panamensis is similar to that of Th. cochunaensis Domínguez 1987 ( Domínguez 1987: fig. 5.2), while these species have quite different structure of male imagines (genitalia of Th. cochunaensis resemble that of Th. niger sp. n.).

Figures

FIGURES 122–132. Thraulodes panamensis sp. n. 122–127, larval exuviae at the same magnification: 122–124, parts of head with labrum and mandibles; 125, left half of pronotum and mesonotum; 126, part of sternum and left pleura with half of metanotum and hind protopteron, left fore, middle and hind legs; 127, abdominal terga and sterna; 128, immature larva with light cuticle and well visible blackish hypodermal markings on abdomen; 129, tergalius III; 130, anterior side of hind femur; 131, anterior side of fore tibia; 132, anterior side of hind tibia (122–127, 130, holotype).

FIGURES 133–142. Thraulodes panamensis sp. n. 133, pterostigma; 134–136, male imago in lateral in ventral and dorsal view; 137–138, left half of subimaginal exuviae of mesonotum of two different specimens; 139, female imago; 140–141, genitalia in lateral and ventral view; 142, costal margin of fore wing (arrows show proximal costal cross veins) (133, 134, 136, 137, 141, 142, holotype).

FIGURES 143–148. Thraulodes panamensis sp. n. 143, genitalia of male imago in lateral view; 144, apex of penis with spearlike roll in dorsal view; 145, genitalia of the same specimen in ventral view; 146, subimaginal exuviae of genitalia at the same magnification; 147, larval exuviae of protogonostyli and protopenis at the same magnification; 148, hind wing (146, 147, holotype). Abbreviations: lp, pateral pouch; tp, telopenis.

FIGURES 149–150. Thraulodes panamensis sp. n., egg.

FIGURES 86–93. Thraulodes telegraphicus. 86, median longitudinal section of labrum in usual condition; 87, the same, in spread condition; 88, labrum in spread condition in dorsal view (setal rows shown as dotted lines); 89, transverse section of hind tibia; 90–93, tergalii I, III, VI and VII. Abbreviations: anter.r, anterior transverse row of setae; dent., five denticles separated by six sensilla; poster.r, posterior transverse row of setae; i.f, inner field of stout pointed setae; i-a.h, inner-anterior recurved hairs; i-a.r, inner-anterior row of stout setae; o-a.r, outer-anterior row of stout setae; o.h, outer hairs; o-p.r, outer-posterior row of stout setae; p.r, row of posterior pointed pectinate setae.

FIGURES 464–473. Thraulodes nigrabdominalis sp. n. (holotype). 464, left half of subimaginal exuviae of mesonotum; 465, 466, male imago; 467–469, fore, middle and hind legs of male imago; 470, subimaginal exuviae of fore leg; 471, genitalia of male imago; 472, apex of penis; 473, subimaginal exuviae of tarsus.