Asthenopodes picteti Hubbard

Molineri, Carlos, Salles, Frederico F. & Peters, Janice G., 2015, Phylogeny and biogeography of Asthenopodinae with a revision of Asthenopus, reinstatement of Asthenopodes, and the description of the new genera Hubbardipes and Priasthenopus (Ephemeroptera, Polymitarcyidae), ZooKeys 478, pp. 45-128 : 72-74

Taxon classification Animalia Ephemeroptera Polymitarcyidae

Asthenopodes picteti Hubbard stat. n. Figs 11 A–D, 12 A–B, 13A, 20A

Palingenia albicans Pictet 1843: 149 (misidentification)

Campsurus albicans , Eaton 1871: 58.

Asthenopus albicans , Ulmer 1920 c: 107, Ulmer 1921: 239, Lestage 1924 c: 39.

Asthenopodes albicans , Ulmer 1924: 26, Traver 1956: 2.

Asthenopodes picteti , Hubbard 1975: 111, Domínguez 1988 a: 24.

Asthenopus picteti , Hubbard and Domínguez 1988: 207, Domínguez et al. 2006: 562.

Type material.

Type material was not studied; it consists of the holotype male imago, damaged, with many parts missing including the genitalia. It is a pinned specimen deposited at Naturistorisches Museum Wien, Hubbard and Domínguez (1988) presented a figure of the holotype forewing.

Additional material. 3 male subimagos from ARGENTINA, Misiones, Parque Provincial Urugua-í, Arroyo Yacutinga, S 25°44'51" − W 54°03'37", 355 m, 30.xi.2001, Domínguez et al. cols.; 8 female and 2 male imagos same data except Arroyo Uruzú, S 25°51'29" − W 54°10'10", 322 m, 25.xi−2.xii.2001; 1 female and 1 male imagos (slides IBN3-93 and 3-96) from URUGUAY, Maldonado, Arroyo de la Quinta, 4.i.1984, M. T. Gillies col. All the material deposited in IBN.

Diagnosis.

Asthenopodes picteti , type species of the genus Asthenopodes ( Ulmer 1924, Traver 1956, Hubbard 1975) presents 7 autapomorphies (Appendix 2) including: thinner male foretibia and slender penes. This species can be distinguished from the other species of the genus by the following combination of characters: 1) general coloration yellowish white (male), darker in female (yellowish light brown); 2) male FW 11.4-11.9 mm, female FW 14.5-19.0 mm, membrane whitish hyaline tinged with yellowish near hind margin; 3) foreleg length 0.9 times the length of FW; 4) pronotum width/length ratio: 1.6-1.9 (male), 1.5-2.3 (female); 5) 14-17 marginal intercalary veins present on the entire margin of FW (Fig. 11A) and HW (Fig. 11B), miv generally longer than distance between longitudinal veins; 6) male FW with 4 to 6 cross veins between Rs and MA basal to Rs fork; 7) ratio total length/basal width of forceps 6.7 (Fig. 12A); 8) penes long and slender (Fig. 12 A–B), male median remnant of styliger plate posterolaterally expanded forming a pair of rounded projections ( “Ll” in Fig. 12B); 9) female sternum VIII, anteromedian sockets present but concolorous with sternum, not evident; 10) egg polar caps only slightly thinner than maximum width of the egg, formed by 6 filaments; medium-sized and small chorionic disks-like structures present (Fig. 13A).

Male imago. Length (mm): body, 9.3-11.2; FW, 11.4-11.9; HW, 5.8-6.2; foreleg, 10.0-10.3; cerci, 30.1. Described in Traver (1956) and Domínguez (1988a). Additions to these descriptions follow: Prothorax width/length: 1.6-1.9. Wings. Hind margin of FW (Fig. 11A) with 14-17 marginal intercalary veins, relatively long; 4-6 cross veins between R and M, basal to R stem; IMP basally free or fused to MP1 by a cross veins, MP2 fused to IMP. HW as in Fig. 11B. Genitalia (Fig. 12 A–B): forceps length/width ratio: 6.7; median remnant of styliger plate with posterolateral corners roundly projecting.

Female adult. Length (mm): body, 11.5-12.6; FW, 14.5-19.0; HW, 6.3-9.4. General coloration yellowish light brown. Head dorsally blackish except on median zone, paler; venter of head yellowish white. Antennae light brown, shaded gray on scape. Thorax yellowish brown with blackish membranes, shaded with brownish gray on pronotum and with black on posteromedian marks on meso- and metanotum. Pronotum width/length: 1.5-2.3. Legs whitish yellow shaded brownish on dorsum of leg I and on apex of femur III. Wings (Fig. 11 C–D), membrane tinged with light brown, veins yellowish brown. Abdomen. Terga brownish with a pale mediolongitudinal line and paler areas on lateral margins on terga I–VII; sterna whitish yellow; female sternum VIII with anteromedian sockets, small and almost not distinguishable. Terminal filament whitish, shorter than tergum VIII; cerci yellowish brown paler apically, 0.5-0.6 times the length of the abdomen (0.2 the length of FW).

Eggs (Fig. 13A). Length, 325−355 µ; width, 215−235 µ. Two large and flat polar caps (maximum width, 155−180 µ), formed by 6 very long coiled threads. Chorionic surface with a fine granulated aspect, with small disk like structures.

Distribution.

Uruguay, Argentina. Asthenopus picteti is here newly recorded from Argentina. The record from Guyana given by Domínguez et al. (2006, p.562) is no longer valid since this material is now considered a different species ( Asthenopodes chumuco see below).

Discussion.

Asthenopodes picteti Hubbard was only partially known from the damaged holotype male from Brazil until Traver (1956) redescribed it (at that time as Asthenopodes albicans ) based on a complete male from Uruguay. Later Hubbard (1975) gave a new name to this species ( Asthenopus picteti ). Domínguez (1988) and Hubbard and Domínguez (1988) presented additional discussion and illustrations of the male imago, from type and non-type material (also collected in Uruguay). The description of Traver (1956) coincides with the new material studied, except for the relation of the male foretibia and forefemur. Traver reported that tibia is 1.33 times the length of femur but we found that it is 1.7 times that length.

Domínguez (1988) reported 2 female imagos collected at the same time than the males he redescribed, but did not presented a formal description of them. Both females and additional ones from Argentina (see list of material) are here shortly described and figured. It is difficult from the material available to determine if the females are in subimaginal or imaginal stage, so they are here referred as “adults”. The females are similar to the sympatric Asthenopodes traverae but can be separated from this species because Asthenopus picteti females are lighter in color, hind femora only shaded black on apex, paired female sockets present but small and hard to distinguish, cerci light colored, abdominal gill sclerites smaller, FW wider with shorter marginal intercalaries joined to main veins and partially anastomosed. The eggs present wider polar caps, only slightly thinner than the egg. Males can be separated from those of Asthenopodes traverae because the hind femora are only shaded black on apex and the penes are much slender.