Thraulodes ludmilae, 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 : 22-26

1. Thraulodes ludmilae sp. n.

( Figs 5–41 )

Etymology. The species in named in honor of Ludmila Sheyko, who collected the single larva and paid attention to its unusual appearance.

Material examined. Holotype: L-S-I ♂ {specimen [XI](10)2018}, PANAMA, Provincia Bocas del Toro, Bosque protector Palo Seco, Altos del Valle , Rio Buris (8°47’37’’N, 82°11’35’’W), 26.I.2018, coll. L. Sheyko & N. Kluge. Paratype: the same locality and collectors, 24–29.I.2018: 1 S-I ♂.

Descriptions.

Larva (single specimen examined). CUTICULAR COLORATION ( Figs 5–10 ). Head and thorax with very contrastingly alternated large dark (i.e. dark brown) areas and large light (i.e. ocher or nearly colorless) areas. Labrum dark; clypeus, anterior part of frons and mandibles light; posterior part of head dark. Pronotum entirely light; mesonotum dark, with medioposterior part (corresponding to imaginal scutellum) light; fore protoptera dark with convex and concave longitudinal veins lighter. Thoracic pleura with sclerites dark; sterna light. Legs mostly light, femora with darker markings. Each abdominal tergum II–IX with anterior part dark, posterior part light, terga IV–V medially also light; abdominal sterna light, sternum IX darker.

HYPODERMAL COLORATION. Unknown; probably, abdominal terga with paired blackish spots corresponding to midway gray spots of imago (as in Fig. 68 ). Tergalii brownish, tracheae black ( Fig. 11 ).

SHAPE AND SETATION. Clypeus parallel-sided; labrum 1.3 times wider than clypeus ( Fig. 6 ). Labrum widest at midlength; 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 13 pectinate setae in apical-ventral row.

Femora: Stout setae on anterior surface parallel-sided and blunt ( Fig. 13 ). Irregular row of hairs near inner margin absent on fore and middle femora, very sparse on hind femur.

Fore tibia ( Fig. 21 ): outer hairs form two separated irregular rows; inner-anterior row of recurved hairs absent; inner-anterior row of stout setae represented by few (2–3) blunt stout setae near tibia base; 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. 24 ): each of three rows of stout setae—outer-anterior, outer-posterior and inner-anterior onesconsists of blunt stout setae of various lengths; hairs located between outer-anterior and outer-posterior rows, form one irregular row (besides row of hairs posteriad of outer-posterior row of stout setae).

Claws with 6–7 denticles on rigid portion, with several minute denticles on articulatory portion.

Tergalii ( Fig. 11 ): each lamella slender, tracheae without visible side branches.

Male genitalia in last larval instar ( Fig. 37 ): protogonostyli separated one from another by narrow and deep emargination. Each protopenis lobe very short, apically rounded, without gonopore-bearing process; gonopore opened caudally-laterally.

Subimago (31, 34, 36, 39). CUTICULAR COLORATION. Cuticle mostly colorless. Flagellum of antenna brownish. Mesonotum with antelateroparapsidal and lateroparapsidal sutures contrastingly colored with dark brown, posterior part of chromozone and some other areas shed with light brownish ( Fig. 34 ). On all legs tibia and tarsus light brownish ( Fig. 31 ). Cuticle of wings colorless, microtrichia light brownish. Caudalii light brownish. Other cuticle of body, legs and gonostyli colorless.

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 25–30, 32–33 , 35, 38, 40, 41 ). Head ocher with brown. Antenna with scapus ocher, pedicellus reddish-brown, flagellum ocher. Dorsal eyes contiguous medially, dull orange.

Prothorax ocher with pair of dark brown spots above coxa. Meso- and metanotum light brown. Lateral sides of pterothorax ocher with brown. Ventral side of pterothorax mostly ocher, with transverse pale orange band crossing anterior part of mesothoracic episterna and basisternum.

Cuticle of legs mostly colorless; on fore leg base of tibia with cuticle brown. Legs with following hypodermal pigmentation on whitish background: Fore femur with small orange spot on anterior side at 1/4 from base and multicolored apical band, occupying distal 0.4 of femur; apical band mainly orange, apically darker, proximally bordered by blackish-brown, on inner side with blackish-brown longitudinal stripe. Fore tibia with orange-brown apex. Middle and hind femora with multicolored pre-apical band within apical 1/3 of femur; pre-apical band mainly orange, proximally bordered by blackish-brown. In holotype, relation of fore femur to fore wing length 55:275; proportions femur/tibia/tarsomeres on fore leg 55:86:2:25:29:11:7; on middle leg 54:67:3:4:3:2:6; on hind leg 65:70:3:4:3:2:6.

Fore and hind wings with dark brown macula on costal brace and bases of Sc and R; longitudinal and cross veins colorless. Costal cross veins proximad of bulla few, colorless and very thin, visible only under high magnification ( Fig. 32 ). Pterostigmatic cross veins not dense, perpendicular to longitudinal veins or slightly oblique, nonbranched. Hind wing with prominent costal projection ( Fig. 41 ).

Abdominal hypodermal coloration: Abdominal tergum I brown. Terga II–VI whitish, translucent, with more or less expressed brown band on posterior margin; terga IV–V or IV–VI with pair of small gray midway spots; tergum IV with poorly expressed median transverse spots; tracheae and stigmata not colored. Tergum VII orange, tergum VIII anteriorly-medially orange and posteriorly-laterally white, terga XI–X orange. Sternum I brown due to hypodermal and cuticular pigmentation ( Fig. 27 ); sterna II–VI whitish, translucent; sternum VII whitish with brown ganglion; sterna VIII–IX whitish, laterally with orange. Caudalii mostly white, with black dot on each joining; larger and smaller dots alternated.

Genitalia ( Figs 33 , 35–40 ): Styliger, gonostyli and penis light ocher. Dorsal extension of styliger finger-like, denticulate, well separated from styliger margin and inserted dorsad of styliger. Penis lobes unusually small and simple, rounded apically, with ventro-median ridges expressed only at very base. Basal lobes (containing seminal pump) not separated from remainder penis. Telopenes very short, delicate, sharply bent ventrally-proximally, with groove shallow, widely opened and exposed ventrally-laterally.

Female and eggs. Unknown.

Dimension. Fore wing length (and approximate body length) 6–6.5 mm.

Comparison. Thraulodes ludmilae sp. n. is related to Th. sinuosus . Male imago of Th. ludmilae sp. n. differs from Th. sinuosus by separated dorsal extension of styliger, extremely shortened spears of penis, presence of orange spot on in proximal part of fore femur and colored apex of fore tibia. Larva of Th. ludmilae sp. n. differs from Th. sinuosus by cuticular coloration with clypeus, pronotum and posterior parts of abdominal terga contrastingly lighter than other areas (individual variability of larvae is not examined). In last instar, male larva of Th. ludmilae sp. n. differs from Th. sinuosus by narrower emargination between protogonostyli and by shorter protopenis.

Figures

FIGURES 5–13. Thraulodes ludmilae sp. n., larval exuviae of holotype (5–10 at the same magnification): 5–7, parts of head with labrum and mandibles; 8, right half of pronotum and mesonotum; 9, part of sternum and left pleura with half of metanotum and hind protopteron, left fore, middle and hind legs; 10, abdominal terga and sterna; 11, tergalii II–III; 12, part of pronotum; 13 anterior side of fore femur.Abbreviation: f.a.m, free anterior margin of pronotum.

FIGURES 14–20. Thraulodes ludmilae sp. n., exuviae of mouthparts of holotype (14, 17–19 at the same magnification): 14, labrum; 15, its anterior margin with focus on dorsal side; 16, the same, with focus on ventral side; 17–18, left and right mandibles; 19, labium and maxilla; 20, dorsal side of glossa.Abbreviations: anter.r, limits of anterior transverse row of setae; poster. r, posterior transverse row of setae; other arrows show six sensilla separating five denticles.

FIGURES 21–24. Thraulodes ludmilae sp. n., exuviae of tibiae of holotype (at the same magnification): 21, anterior side of fore leg; 22, anterior side of middle leg; 23, posterior side of hind leg; 24, anterior side of hind leg.

FIGURES 25–34. Thraulodes ludmilae sp. n.: 25, 27, male imago; 26, apex of fore wing; 28–30, fore, middle and hind legs of male imago; 31, subimaginal exuviae of hind leg; 32, costal margin of fore wing (arrows show proximal costal cross veins); 33, genitalia of male imago; 34, left half of subimaginal exuviae of mesonotum (25–26, 28–34, holotype).

FIGURES 35–41. Thraulodes ludmilae sp. n.: 35, genitalia of male imago in ventral view; 36, subimaginal exuviae of styliger and gonostyli at the same magnification; 37, larval exuviae of protogonostyli and protopenis at the same magnification; 38, imaginal styliger and penis enlarged; 39, subimaginal exuviae of penis at the same magnification; 40, genitalia of male imago in lateral view; 41, hind wing (35–39, 41, holotype). Abbreviations: bl, basal lobe; gr, groove of telopenis; dp, dorsal projection of styliger; m-v.r, medio-ventral ridge (recurved flap); tp, telopenis.

FIGURES 66–69. Thraulodes telegraphicus. 66–67, last instar larvae with intensive cuticular coloration and poorly visible hypodermal coloration; 68, younger larva with light cuticle and well visible blackish hypodermal markings on abdomen; 69, claw. Abbreviations: artic.p., articulatory portion; rigid p., rigid portion of claw.

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.