Tortopus igaranus Needham & Murphy

Molineri, Carlos, 2010, A cladistic revision of Tor top us Needham & Murphy with description of the new genus Tortopsis (Ephemeroptera: Polymitarcyidae), Zootaxa 2481, pp. 1-36 : 11-15

Tortopus igaranus Needham & Murphy

Tortopus igaranus Needham & Murphy, 1924:24 (female) in part

Type material ( CUIC). Types in alcohol: holotype (female abdomen) and 4 female paratypes from Peru, río Putumayo between Puerto Alfonso and the mouth of the Igará-Paraná, 14-VIII-1920. One female specimen from Perú, río Igará-Paraná, 15-17-VII-1920 (1 pair of wings dissected, CUIC slide No. 629.3); and 1 female (body without wings, very damaged) from Peru, Puerto Bermudez (no more data). Type slides: the two holotype slides (No. 629.1) were not studied, CUIC reported them as completely broken and with missing parts. Paratype slides: No. 629.3 correspond to the female from Igará-Paraná mentioned above, but the slide (1 wing pair) presents the following data (presumably a mistake): blue carton “ PARATYPE /Cornell U./ No.629.3”, white carton “Cornell University/N0 654/ SUB. 14 SL.Ƥ/ Tortopus / Campsurus / igaranus /Rio Putumayo/ DATE 14 Aug.´20 Peru ”.

The following material is removed from the type series since they represent female adults of a different species: six females originally designated as paratypes ( Needham & Murphy 1924), were removed from the vial containing the holotype ( Peru, río Putumayo between Puerto Alfonso and the mouth of the Igará-Paraná, 14-VIII-1920). The slides No. 629.2, 629.4 and 629.5 are not conspecific with the holotype, the bodies in alcohol that correspond to the slides 629.2 and 629.4 are among the 6 females mentioned above (the slide 629.5 does not have an associated specimen in alcohol). Additional material ( IML). Five male and 4 female imagos from Colombia: Depto. Amazonas, Leticia, Isla Beatriz, 93 m, 8-II-1999, S 4º 4' 23" W 69º 59' 12", light trap 18–20 h, M. C. Zúñiga, E. Domínguez & C. Molineri cols.

Holotype (only female abdominal segments VII–X). Eggs orangeish. Abdominal tergum VII damaged, incomplete; terga VIII–X shaded slightly with gray, lighter in X. Abdominal sterna without gray shading, parastyli receptors on sternum VIII relatively small and near the medial line, with paired shallow longitudinal furrows directed anteriorly from each socket (Fig. 7). Cerci translucent yellowish white, vestigial terminal filament translucent whitish.

Paratype female adults. One of the four specimens from Putumayo river is much damaged presenting only the thorax and the wings (fore wings, 12.5 mm; hind wings, 5.0). The other 3 are in better condition (one of them with a pair of wings dissected, without associated slide), body length: 7.0 (shrunken specimen)- 8.5 mm; fore wings, 9.8–10.0 mm; hind wings, 3.5–3.9 mm. The paratype specimen from Igaraná-Paraná (and associated slide) is in a rather good condition, measures: body, 6.5 mm (shrunken), fore wing 10.2 mm, hind wing, 3.9 mm. General coloration yellowish white, eggs orangeish. Head with a whitish triangular mark behind median ocellus, occiput with a pair of grayish oblique bands extending from each lateral ocellus to the medial line near hind margin (Fig. 5). Antennae: scape and pedicel yellowish tinted with gray, flagellum hyaline. Thorax. Pronotum markedly convex dorsally, with well developed anterior hump; shaded with gray except laterally, medial line whitish, anterior margin shaded with gray sublaterally. Mesonotum whitish yellow, except medioposterior zone whitish, anterior phragma orangeish. Metanotum whitish medially, rest yellowish. Thoracic sterna pale, furcasternal protuberances with divergent medial margins (Fig. 4). Legs whitish except coxae yellowish. Wings. Membrane hyaline to whitish translucent, longitudinal veins yellowish brown, cross veins whitish; R3 and short intercalary vein before it present in fore wings (Fig. 8); reticulate pattern of cross veins in anal region of hind wings slightly marked (Fig. 9). Abdomen. Terga translucent whitish slightly and widely shaded with gray, darker on terga VIII–IX, tergum X whitish. Abdominal sterna pale, parastyli receptors (Fig. 6) on sternum VIII as holotype.

Length of voucher female imagos (collected with the males described below): body, 9.0– 9.2 mm; fore wings, 8.5–10.0 mm; hind wings, 3.5–3.6 mm; cerci, 2.2–2.7 mm.

Eggs ( Figs. 67–69 ). Subcircular outline. Length, 325 µm; width, 300 µm. No attachment device present. The convex area of the egg is sculptured with pentagonal and hexagonal cells ( Fig. 68 ). The concave area shows a regular arrangement of shallow circular grooves ( Fig. 69 ). The entire zone forming the margin between the above mentioned areas is smooth ( Fig. 67 ).

Male imago. Length (mm): body, 7.5–9.8; fore wing, 8.0–8.9; hind wing, 3.4–3.9 mm; fore leg (from base of coxae to apex of claw), 3.7–4.0; cerci, 20.0–22.0. General coloration whitish yellow. Head whitish shaded gray on pair of oblique bands on occiput, each band extending from lateral ocellus posteriorly towards medial line. Antennae: scape and pedicel whitish shaded light gray, flagellum hyaline. Thorax. Pronotum dorsally convex, anterior ring hyaline translucent, projecting anteriorly ("anterior hump"), a blackish marks is present laterally on fore margin; posterior ring of pronotum whitish translucent shaded with gray medially; propleura and presternum hyaline to whitish translucent. Mesonotum whitish yellow with darker margins and carinae, shaded slightly with gray along medioparapsidal sutures and inner margins of posterior scutal protuberances. Metanotum whitish translucent shaded gray anteromedially. Meso- and metaplaurae and sterna pale. Legs yellowish white, shaded with light gray on fore leg, more markedly on fore tibiae and tarsi, except intertarsal joinings. Wings. Membrane hyaline except apical third of C and Sc area whitish translucent; veins whitish translucent shaded with gray on veins Sc and RA. Abdomen whitish translucent shaded gray dorsally, very slightly on anterior segments but darkening posteriorly; terga III–VII with a pair of submedian bands, each band turns laterally towards hind margin; terga VIII–X shaded more widely, stronger on hind margin of tergum X; medial line of all terga pale. Abdominal sterna pale, with blackish spot in the middle of sternum IX. Genitalia whitish except parastyli and outer margin of penes yellowish. Caudal filaments whitish translucent except basal segment yellowish.

Discussion and diagnosis. From the study of the type series, two groups of females representing two different genera ( Tortopus and Tortopsis ) were distinguished. Fortunately, the holotype abdomen in alcohol was preserved enough to show important characters for species identification (holotype slides were reported as broken and with lost parts). The holotype and conespecific paratypes of T. igaranus were compared to newly collected material from sites near to the type localities. Descriptions given above are based on this morphotype. The abdomens of the above described paratypes coincide completely with the holotype in morphology and coloration, including the shape of the parastyli receptors. Veins R3 and the short intercalary before it on fore wings are hard to distinguish in the relatively damaged wings of the paratypes, they are present in one slide ( CUIC No. 629.3) and on one of the specimens in alcohol.

The holotype and the 4 conspecific paratypes of T. igaranus present the following characters: head coloration formed mainly by a pair of oblique bands running from lateral ocelli to medial posterior line; mesonotum without a gray marking before mesoscutellum; furcasternal protuberances diverging from its anterior portion; fore wing with R3 and short intercalary vein before it; cross veins in fore and hind wings whitish; parastyli receptors on sterna VIII small and submedian.

The six females from río Putumayo here excluded from the type series represents a different species in the genus Tortopsis . These specimens can be distinguished from the holotype and paratypes referred above by the following characters: head coloration more extended in occiput; pronotum in dorsal view rectangular, with well separated anterior and posterior rings; mesonotum with a gray V-shaped marking before mesoscutellum; furcasternal protuberances with parallel sides on anterior half, diverging only on the posterior portion; veins R3 and short intercalary before it absent in fore wing; cross veins in fore and hind wings as dark as longitudinal veins; parastyli receptors on sterna VIII C-shaped and relatively large, more lateral in position. These specimens could be the female of Tortopsis unguiculatus (Ulmer) or a new species, but their overall bad condition necessitates leaving them unnamed.

Tortopus igaranus can be distinguished from all other species in the genus by the following combination of characters: 1) fore wing length 8.0– 8.9 mm (female 8.5–12.5 mm); 2) parastyli relatively long (1.5 times length of pedestal) and thin from its base (Figs. 2–3); 3) ventral knob relatively small (Fig. 2); 4) penes not strongly expanded (Fig. 2); 5) female with sockets on s. VIII with oblique opening as in Figs. 6–7; and 6) a very pale species, head shaded gray in a pair of oblique bands from lateral ocelli to hind margin.

Figures

FIGURES 67 – 72. SEM photographs. Tortopus igaranus: 67, egg, general view; 68, egg, detail of convex side; 69, egg, detail of concave side. Tortopus arenales: 70, female abdominal sternum VIII; 71, same, detail of sockets; 72, eggs.