Thraulodes consortis Domínguez 1987

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 : 136-139

21. Thraulodes consortis Domínguez 1987 (?)

( Figs 654–672 )

Thraulodes consortis Domínguez 1987: 55 (♂ and ♀ imagines, larva, eggs).

Material examined. ARGENTINA: Provincia Jujuy, P.N. Calilegua: Rio Aguas Negras and Rio San Lorenzo , 26.VIII.1998, coll. L. Zhiltzova: 1 S ♂, 16 larvae. Provincia Tucuman: Quebrada de Los Sosa and its tributaries, 21 and 30.VIII.1998, coll. L. Zhiltzova: 10 larvae.

Descriptions.

Larva. CUTICULAR COLORATION. Brown, with diffusive blanks.

HYPODERMAL COLORATION. Abdominal terga II–VII or II–VI with pair of blackish transverse sublateral maculae (as in imago) ( Fig. 657 ). Tergalii gray ( Figs 666–672 ).

SHAPE AND SETATION. Clypeus slightly widened distally; labrum 1.3–1.4 times wider than clypeus. Labrum widest at 0.4 length from base, with lateral sides angulate; fore margin (often turned ventrally), without median emargination, with all 5 denticles wide; anterior transverse setal row regular (as in Fig. 88 ), as wide as all 5 denticles. Maxilla with 13–14 pectinate setae in apical-ventral row.

Femora: Stout setae on anterior surface widened distally or parallel-sided, apically rounded ( Fig. 662 ). Irregular row of hairs near inner margin present on all femora.

Fore tibia ( Fig. 663 ): outer hairs form two irregular rows; inner-anterior row of recurved hairs absent; inner-anterior row of stout setae represented by few (2–5) blunt stout setae near tibia base; inner field of stout pointed setae dense (i.e. setae longer than distances between them), consists of pointed bipectinate and smooth setae, situated irregularly (about 3 setae in cross section).

Hind tibia ( Figs 664–665 ): outer-anterior row of stout setae consists of two clearly different types of stout setae: numerous short widened distally and blunt ones and several long spoon-like ones; outer-posterior row of stout setae consists of blunt stout setae of various lengths and long spoon-like stout setae; 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 several minute denticles on articulatory portion.

Tergalii ( Figs 666–672 ): very wide; on both lamellae main trachea with many branches directed toward costal and anal margins; dorsal lamella with costal and anal margins equally convex in proximal and distal parts, abruptly narrowed toward apex, with slender apical filament; ventral lamella widest near base, gradually narrowed toward apex, with slender apical filament.

Male genitalia in last larval instar ( Fig. 654 ): protogonostyli separated one from another by deep emargination. Each protopenes lobe with lateral margin semicircular; gonopore-bearing process short, sharply projected caudally and located near median margin; gonopore opened caudally-laterally.

Subimago. CUTICULAR COLORATION. Mesonotum mostly brown, with darker brown antelateroparapsidal and lateroparapsidal sutures, colorless oblique stripes on posterior scutal protuberances and colorless achromozones; chromozones brown, medioscutal chromozone somewhat darker than submedioscutal chromozone (as in Th. nigrotibialis — Fig. 522 ). On all legs femur bordered by brown on outer and inner margins and apically; fore tibia brown proximally and apically, middle and hind tibiae brown only proximally. Cuticle of wings colorless, microtrichia 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 ).

Imago. Not examined. Coloration of imaginal legs and abdomen visible through subimaginal cuticle ( Figs 658–660 ). Judging by venation of fore wing of subimago and fore protopteron of last instar larva, in imaginal fore wing ICu 2 joined to ICu 1, but not to CuP; cross veins present in costal field proximad of bulla ( Fig. 655 ). Judging by hypodermal pigmentation of fore wing of subimago and fore protopteron of last instar larva, imaginal fore wing has following coloration ( Fig. 655 ): in anterior part of wing cross veins bordered by brown, especially widely in proximal half of costal and subcostal fields; brown macula on area of costal brace; large brown macula on bulla; small brown dot on posterior branch of RS posteriad of bulla; furcation of MA colored by brown. Judging by hypodermal pigmentation of hind wing of subimago and hind protopteron of last instar larva, imaginal hind wing has brown macula on area of costal brace ( Fig. 656 ).

Dimension. Fore wing length (and approximate body length) 10 mm.

Discussion. Larvae and subimago described above are associated based on the same hypodermal coloration of legs and abdomen and the same venation and hypodermal coloration of larval protoptera and subimaginal wings. Larval characters agree with the descriptions of Th. consortis Domínguez 1987 and Th. liminaris Domínguez 1987 .

In contrast to larvae and subimago described here, in the descriptions of Th. consortis and Th. liminaris , brown maculae on bulla, RS and MA are not reported and not figured ( Domínguez 1987: figs 2–3).

According to wing venation (ICu 2 joined to ICu 1, but not to CuP) these larvae agree with the description of Th. consortis , but not Th. liminaris . Domínguez (1987) reported difference between larvae of Th. consortis and Th. liminaris in structure of fore leg claw, which for Th. consortis was said to have «six or seven denticles progressively larger apically, except the apical denticle slightly larger» and for Th. liminaris was said to have «six denticles progressively larger apically» ( Domínguez 1987: figs 25–26, Domínguez et al. 2006: figs 191I–J); nothing was said about claws of middle and hind legs. In the examined larvae, rigid portion of claws of all legs have from 6 to 9 denticles varying in relative size, so that this character does not distinguish Th. consortis from Th. liminaris .

Figures

FIGURES 654–665. Thraulodes? consortis. 654, larval protogonostyli and protopenis; 655, fore protopteron; 656, hind protopteron; 657, larva with ocher cuticular coloration and blackish hypodermal markings on head and abdomen; 658–660, fore, middle and hind legs of male subimago; 661, abdominal terga and sterna of male subimago; 662, anterior side of hind femur; 663, anterior side of fore tibia; 664, hind tibia with focus on outer-posterior row of stout setae; 665, the same with focus on outer-anterior and inner-anterior rows of stout setae.

FIGURES 666–672. Thraulodes? consortis, tergalii I–VII.

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 522–531. Thraulodes nigrotibialis sp. n. 522, right half of subimaginal exuviae of mesonotum; 523, head and thorax of male imago in lateral view; 524–525, female imago in dorsal and lateral view; 526–527, fore and middle leg of male imago; 528, abdominal terga and sterna of male imago; 529–530, genitalia of male imago with focus on styliger and on penis; 531, genitalia of male subimago extracted from larva (522–523, 526–530, holotype).

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.