Thraulodes viviparus, 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 : 50-52

5. Thraulodes viviparus sp. n.

( Figs 151–173 )

Etymology. This species is assumed to be ovoviviparous.

Material examined. Holotype: S-I ♂ {specimen [ XIV](B)2013}: PANAMA: Provincia Bocas del Toro, Bosque protector Palo Seco, Altos del Valle , Rio Buris (8°47’37’’N, 82°11’35’’W), 29.I.2018, coll. N. Kluge & L. Sheyko. Paratypes: the same locality and collectors, 26.I.2018: 1 S-I ♀; 24–28.I.2018: 1 larva (presumably associated).

Descriptions. Larva (presumably associated). CUTICULAR COLORATION ( Fig. 154 ): Dorsal side of head dark brown. Dorsal side of thorax mostly dark brown with small contrasting blanks. Abdominal terga brown, with blanks near tergalii bases, terga IV, V, VIII and IX with contrasting unpaired blanks medially. Femora brown with blanks; tibiae and tarsi uniformly light brown.

HYPODERMAL COLORATION.Abdominal terga III–VI, besides cuticular coloration (see above) with pair of transverse blackish spots (corresponding to midway gray spots of imago) and blackish spiracular spots ( Fig. 155 ). Tergalii brownish with costal areas gray, tracheae black ( Fig. 153 ).

SHAPE AND SETATION. Clypeus widened distally; labrum 1.4 times wider than clypeus. Labrum widest at 1/3 of length from base; initial fore margin (turned ventrally) without median emargination, with all 5 denticles wide (as in Fig. 88 ); anterior transverse setal row regular, wider than 3 denticles. Maxilla with 18 pectinate setae in apical-ventral row.

Femora: Stout setae on anterior surface parallel-sided or narrowed distally, occasionally widened distally, apically rounded or truncate ( Figs. 152 ). Irregular row of hairs near inner margin absent on fore femur, present on middle and hind femora.

Fore tibia: outer hairs form two irregular rows; inner-anterior row of recurved hairs absent; inner-anterior 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 mostly one row.

Hind tibia ( Fig. 151 ): both outer-anterior and outer-posterior rows of stout setae consist of various stout setae: short rounded, long spoon-like and intermediate ones; posterior hairs located between these rows, form more than one row (besides row of hairs posteriad of outer-posterior row of stout setae); stout setae of inner-anterior row moderately long, mostly narrowed distally, apically rounded.

Claws with 6 denticles on rigid portion, with pointed denticles on articulatory portion.

Tergalii ( Fig. 153 ): each lamella moderately wide, tracheae with few small side branches.

Male genitalia in last larval instar ( Fig. 172 ): protogonostyli short and separated one from another by shallow emargination. Each protopenis lobe with small, sharply projected gonopore-bearing process; gonopores opened caudally-laterally.

Subimago ( Figs 165 , 170 ). CUTICULAR COLORATION. Cuticle mostly colorless, with brown areas. Flagellum of antenna brown. Pronotum colorless. Mesonotum mostly colorless, with contrasting brown antelateroparapsidal and lateroparapsidal sutures, anteronotal transverse impression and chromozone of medioscutum; chromozone of submedioscutum nearly colorless ( Fig. 165 ). Thoracic pleura and sterna colorless. On each leg femur colorless, in distal part with inner and outer margins shed with brownish; tibia and tarsus light brown. Cuticle of wings colorless, microtrichia light brownish. Abdominal terga mostly colorless; terga II–IX with diffusive brown median stripe; tergum VI with wider median area diffusively light brownish. Caudalii light 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 156–161, 165–168 , 169, 171 ). Head brown. Antenna with scapus ocher, pedicellus brown, flagellum ocher. Dorsal eyes contiguous medially, dull orange.

Prothorax light ocher with pair of dark brown spots above coxa. Pterothorax brown with ocher; metathoracic scutellum apically brown ( Fig. 159 ); prosternum anteriorly dark, posteriorly ocher; furcasternal protuberances and furcasternal median impression equally brown ( Fig. 158 ).

Cuticle of legs mostly colorless; on fore leg apex of femur with cuticle light brownish. Legs with following hypodermal pigmentation on whitish background ( Figs 160–161 ): Fore femur with triangular orange 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 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 side with blackish-brown longitudinal stripe; apex of femur non-colored. In holotype, relation of fore femur to fore wing length 82:355; proportions femur/tibia/tarsomeres on fore leg 82:110:3:29:22:15:10; on middle leg 77:85:3:5:3:3:9; on hind leg 95:90:3:5:3:3:9.

Fore wing with dark brown macula just distad of costal brace and light brown band crossing wing posteriad of costal brace; costal brace lighter orange; very base of fore wing non-colored. Hind wing with dark brown macula on costal brace and bases of Sc and R. On all wings longitudinal and cross veins colorless. Costal cross veins proximad of bulla few, colorless and very thin, so that visible only under high magnification (as in Fig. 142 ). Pterostigmatic cross veins moderately dense, oblique, arched, non-branched ( Fig. 156 ). Hind wing with prominent costal projection ( Fig. 173 ).

Abdominal hypodermal coloration: Tergum I brown. Terga II–VI ocher, translucent, with light brown band on posterior margin; terga III–VI with pair of small gray midway spots; terga IV–VI with small diffusive orange stripe medially; pleura with blackish stigmatic dots. Tergum VII mainly orange, tergum VIII anteriorly-medially orange and posteriorly-laterally ocher, terga XI–X mainly orange. Sterna I–VI ocher, translucent; sterna VII–IX ocher with lateral sides colored with brownish and orange. Caudalii with segments alternated as following: black, white, white with base black, white; all joinings black.

Genitalia ( Figs 167–168 , 169–171 ): Styliger and gonostyli light ocher. Dorsal extension of styliger narrow and prominent. Penis lobes not long, markedly widened apically, with narrow lateral pouches. Telopenes in form of spear-like rolls, attached on dorsal side and directed medially-dorsally, nearly straight, with groove opened dorsallylaterally ( Fig. 171 ).

Female imago ( Figs 162–164 ). Pronotum medially brown with ocher, laterally whitish; abdominal terga II–VI brown with ocher; in other respects coloration similar to that of male.

Eggs. Chorion absent. In the single examined non-fecundated female imago, abdomen is entirely filled with polygonal eggs with smooth surfaces closely pressed one to another; no one egg has developed or developing chorion.

Dimension. Fore wing length (and approximate body length) 8.5–9 mm.

Comments. Male and female imagines, reared from subimagines, were associated by similar coloration of thorax, wings, legs and caudalii of imago and coloration of subimaginal exuviae; particularly, presence of brown band posteriad of costal brace ( Figs 157–159, 162–164 ) allowed to separate them from the similar sympatric species Th. panamensis sp. n., Th. marreroi , Th. sinuosus and Th. ludmilae sp. n.; in addition to this, brown color of metathoracic scutellum ( Figs 159, 164 ) distinguishes Th. viviparus from Th. panamensis sp. n.; brown medioscutal chromozone on subimaginal exuviae ( Fig. 165 ) distinguishes Th. viviparus from Th. sinuosus and Th. ludmilae sp. n.

A single male larva of last instar has no developing imaginal details, and venation of its protoptera is not preserved. Its association with Th. viviparus sp. n. is based only on blackish spots corresponding to the midway and spiracular spots of imago, the same size as in imago and the same locality. Among species of Thraulodes known from Panama, midway spots on abdominal terga III–VI and spiracular spots are present also in Th. panamensis sp. n., Th. sinuosus and Th. marreroi ; these species have smaller size; larvae of these three species are associated by rearing and differ from the larva presumably ascribed to Th. viviparus sp. n.

Comparison. Th. viviparus sp. n. differs from all other species by absence of sculptured chorion on eggs. By penis structure and coloration of legs and abdomen Th. viviparus sp. n. is similar to Th. guanare Chacón, Segnini & Domínguez 1999 , which was described as male and female imagines from Venezuela; egg structure of Th. guanare was not reported. Imagines of Th. viviparus sp. n. differ from Th. guanare by wider multicolored macula at wing base (instead of black spot in Th. guanare ) and proportion of penis, which in Th. viviparus sp. n. is shorter and wider than in Th. guanare . From the sympatric species Th. panamensis sp. n., imagines of Th. viviparus sp. n. can be distinguished by absence of white spot on scutellum, coloration of wing base and shape of penis.

Figures

FIGURES 151–155. Larva presumably attributed to Thraulodes viviparus sp. n. 151, anterior side of hind tibia; 152, anterior side of hind femur; 153, tergalius VII; 154, general view; 155, abdominal terga spread on slide (with brown and whitish cuticular coloration and blackish paired hypodermal markings).

FIGURES 156–168. Thraulodes viviparus sp. n. 156, pterostigma; 157–159, head and thorax of male imago in lateral in ventral and dorsal view; 160–161, fore and hind legs of male imago; 162–164, female imago in ventral in dorsal and lateral view; 165, left half of subimaginal exuviae of mesonotum; 166, abdominal terga and sterna; 167–168, penis with focus on dorsal and ventral side (156–161, 165–168, holotype).

FIGURES 169–173. Thraulodes viviparus sp. n. 169, genitalia of male imago in ventral view; 170, their subimaginal exuviae at the same magnification; 171, apex of penis in dorsal view; 172, protogonostyli and protopenis of presumably associated larva; 173, hind wing (169–171, 173, holotype). Abbreviations: lp, pateral pouch; tp, telopenis.

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.

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).