Thraulodes alapictus, Lima, Lucas R. C., Mariano, Rodolfo & Pinheiro, Ulisses, 2013

Lima, Lucas R. C., Mariano, Rodolfo & Pinheiro, Ulisses, 2013, New species for Thraulodes Ulmer, 1920 (Ephemeroptera: Leptophlebiidae: Atalophlebiinae) and the first key to adults from Brazil, Zootaxa 3709 (3), pp. 230-242 : 237-238

Thraulodes alapictus sp. nov., Mariano & Lima

( Figs. 6–7 ; 14–15; 27–30)

Diagnosis. The male imago of this species can be separated from all the other congeners by a combination of the following characters: (1) costal membrane basal to bulla with 10 cross veins ( Fig. 6 ); (2) costal and subcostal zones of the forewing translucent ( Fig. 6 ); (3) forewing hyaline with cross veins tinged with brown, with a central brown spot on MA fork ( Fig. 6 , 27 ); (4) two dark brown bands in median region of femora ( Fig. 27, 30 ); (5) spines of penes long and narrow, apicolateral area forming an “ear”, lateral pouch absent, and without recurved folds parallel to inner margin ( Figs. 14–15 ).

Male imago. Length: body, 11.5 mm; forewing, 11.1 mm; hind wings, 2.8 mm; general coloration light brown.

Head ( Figs. 27–28 ): black; antenna light brown with scape brown; upper portion of eye reddish brown, lower portion black; ocelli white with a black ring at base.

Thorax ( Figs. 28–29 ): pro-, meso and metanotum brown. Pronotum with a medial triangular dark spot. Meso and metanotum light brown with sutures dark brown; recurrent scuto-scutellar suture brown. Pleura whitish washed with some red spots; episternum of prothorax white tinged with purple; mesosternum dark brown with a medial white macula; metasternum dark brown.

Wings ( Figs. 6–7 ): membrane of forewing hyaline, tinged with light brown on fork of MA vein, and with dark spot near base; costal and subcostal zones translucent. Longitudinal veins light brown; costal and subcostal cross veins blackish, lighter towards apex. Veins ICu2 and CuP joined basally. Costal membrane with 10 cross veins basal to bulla and 15 cross veins distal to bulla. Hind wing hyaline with 13 light brown cross veins, with dark spot near base.

Legs: legs with femur yellowish, apical 1/3 of femur tinged with reddish followed by two black marks in median region, apex black; tibiae yellowish with apex black and a small blackish spot on the base; tarsi yellowish tinged with black with the last tarsomere darker.

Abdomen ( Figs. 27–28 ): general coloration translucent brown; tergum I brown washed with black; terga II–VI translucent brown with anterolateral dark spots and a medial light brown macula decreasing toward tergum VI; terga IV–VI with minute medial dark spots; terga VII brown; VIII–X reddish brown. Sternum I–II brown; sterna III–VI translucent, VII–IX whitish; four minute marks on sterna III–VIII.

Genitalia ( Figs 14–15 ): forceps whitish with inner margin washed with black. Posterior margin of subgenital plate rounded with a minute medial projection. Penes yellowish washed with black on ventral inner region; 2/3 of penes divided apically, with a pair of long and narrow spines, 3.0x the width of penes; apicolateral area forming an “ear”; external margin not forming lateral pouch and without recurved folds parallel to inner margin. Terminal filament whitish with base of segments black.

Female imago ( Fig. 30 ). Length: body, 11.9 mm; forewing, 11.1 mm; hind wing, 2.3 mm; general coloration brown. Head: black ventrally and whitish tinged with purple dorsally. Thorax: Pronotum brown with a medial dark line. Mesonotum and metanotum light brown with sutures whitish. Prosternum purple with median region whitish. Mesosternum purple with episternum and furcasternum brown. Metasternum brown. Legs: Same as male, except by general coloration of femora and tibiae darker. Abdomen entirely dark brown without segments translucent.

Nymph. Unknown

Type material. Holotype: one male imago, Brazil, Santa Catarina State, Urubici, Cachoeira Avental, 28°02.798’S, 49°37.070’W, 1229m, 08.i.2010, light trap, L.C. Pinho, H.F. Mendes & R. Moreto colls ( MZUESC). Paratype: same as preceding, one male and four female imagos ( CZNC).

Etymology. From the latin words, ala (wing) and pictus (point), due to macula on the central region of forewings.

Remarks. Thraulodes basimaculatus Giordano & Domínguez, 2005 from Bolivia is another species of this genus that has the forewing membrane pigmented. However, in the new species this pigmentation is a central spot restricted to fork of MA vein, whereas in T. basimaculatus most of the basal half and the entire membrane of the hind wing is pigmented. Thraulodes alapictus sp. nov., T. liminaris Domínguez, 1987 from Argentina, T. brunneus Koss, 1966 from USA (New Mexico), Honduras and Guatemala, and T. mexicanus (Eaton, 1884) from Mexico and Central America are the only ones that have the vein ICu2 of forewing joined at base to vein CuP. However, T. liminaris seems more related to T. alapictus sp. nov. by the following characteristics: large body length (over 10 mm), the costal area of forewing with numerous cross veins basal to bulla (over 10 cross veins), and a pair of long and narrow subapical spines on penes. The new species is easily distinguished from it by the abdominal color pattern with translucent segments, the presence of a central brown spot on forewing, with costal and subcostal areas hyaline, and the posterior margin of subgenital plate rounded (almost straight with medial rounded projection in T. liminaris ).

Figures

FIGURES 2 – 9. Wings of male imagos. 2, Thraulodes luizgonzagai sp. nov., forewing; 3, idem, hind wing; 4, T. sternimaculatus sp. nov., forewing; 5, idem, hind wing; 6, T. alapictus sp. nov., forewing; 7, idem, hind wing; 8, T. pinhoi sp, nov., forewing; 9, idem, hind wing.

FIGURES 27 – 30. Thraulodes alapictus sp. nov.: 27, lateral view; 28, dorsal view; 29, detail of prosternum; 30, lateral view of female imago (scales: 1 mm).

FIGURES 10 – 17. Genitalia of male imagos. 10, Thraulodes luizgonzagai sp. nov., genitalia (ventral view); 11, idem, penes (ventral view); 12, T. sternimaculatus sp. nov., genitalia (ventral view); 13, idem, penes (ventral view); 14, T. alapictus sp. nov., genitalia (ventral view); 15, idem, penes (ventral view); 16, T. pinhoi sp, nov. genitalia (ventral view); 17, idem, penes (ventral view).