Campsurus latipennis (Walker), 1853

Molineri, Carlos & Salles, Frederico F., 2017, Review of selected species of Campsurus Eaton 1868 (Ephemeroptera: Polymitarcyidae), with description of eleven new species and a key to male imagos of the genus, Zootaxa 4300 (3), pp. 301-354 : 303-307

Campsurus latipennis (Walker)

( Figs. 1–24 , 163 )

Palingenia latipennis Walker, 1853: 554 ; Hagen, 1861: 304.

Campsurus latipennis ; Kimmins, 1960: 313 (male); Domínguez et al. 2006: 572.

Type material. Photographs of the lectotype male subimago and lectoallotype alate female (both pinned), in the British Museum , from " Para, 49–I " ( Kimmins 1960: 313).

Additional material. BRAZIL: 200 ♂ i from Espírito Santo, Linhares, Lagoa Nova, S 19° 25' 7.2" – W 40° 9' 26.4", 17 m, 12.ix.2009, light-trap, Salles F. leg. ( CZNC); 3 ♂ i, 1♀ msi, alate 7 ♀ and 3 last instar ♂ nymphal cuticles from Espírito Santo, Linhares, Palminhas, Rio Doce, 9–10.ix.2014, Salles F. leg. (IBN); and 6 ♂ i (wings on slide IBN527CM) from Tocantins (TO), Ilha Bananal, rio Araguaia , (approx. S 5° 24' / W 48° 37'), 10.xi.1953, AA Pesle col. (IBN).

Male imago. Length (mm): body, 9.8–17.3; fore wing, 8.4–13.5; hind wing, 4.3–6.5; cerci, 22.0–35.0; fore leg, 4.2–5.5. General coloration whitish with well-defined gray markings. Head yellowish white, almost completely shaded with black dorsally ( Fig. 163 ). Antennae whitish translucent, shaded with gray. Thorax ( Fig. 163 ). Pronotum translucent, anterior portion almost completely shaded with gray, darker at medial line, pronotal hump (ph in Fig. 163 ) translucent; posterior pronotal portion translucent, shaded with black on margins; prosternum with area between coxae gray. Mesonotum yellowish, almost completely shaded with gray except for unpigmented anteronotal projection (ap), and blackish medioparapsidal suture (mps in Fig. 163 ) and area between posterolateral protuberances ( PSP in Fig. 163 ); pleura yellowish except PLsS (superior pleural suture) blackish and sternum shaded black on area between anterior furcasternal protuberances; metanotum, shaded medially with gray, metasternum with submedian black subcircular mark. Legs: fore legs whitish, almost completely shaded with gray; fore coxa with two dark-grayish marks; middle and hind legs yellowish translucent. Wings. Membrane hyaline except base and fore margin purplish gray; fore wings with veins C, Sc and R1 purplish gray, lighter toward apex; other longitudinal and cross veins shaded slightly with gray except from MP2 toward base; hind wing with base and subcostal veins purplish grayish. Abdomen ( Fig. 163 ) translucent whitish shaded with gray on terga as in Fig. 163 , slightly paler medial line present on some terga; abdominal sterna pale without shading, except remnants of gill insertions and apical third of sterna VII–VIII shaded light grayish. Genitalia ( Figs. 1–6, 9–12 ): sternum IX with grayish medial triangle and blackish hind margin, with blunt medial projection ( Figs. 1 mp) and microsculptured with fine, long and simple microtrichiae ( Fig. 10 ); pedestal bases well separated from each other ( Figs. 1, 3, 9 ), pedestals yellowish white, with outer apical corner projected forming relatively short and blunt parastylus (ps in Fig. 2 ); forceps whitish; penes whitish except dorsal sclerotized margin yellowish, base of penes (bp in Figs. 1, 9 ) large and subquadrangular, main lobe of penes (ml in Figs. 1, 9 ) subconical with subapically indented dorsal margin (in lateral view, arrows in Figs. 4–5 ), apical portion twisted, secondary lobe of penes (sl in Figs. 1, 9 ) small, membranous and subcylindrical. Caudal filament translucent whitish.

Alate female. Length (mm): body, 11.0–16.5; fore wing, 12.5–16.0; hind wing, 5.3–6.5; cerci, 3.8–4.5; fore leg, 1.4–1.5. General aspect and color pattern similar to male imago. Abdominal sternum VIII with anteromedian paired sockets, sockets fused with each other medially, shallow ( Figs. 7–8 ).

Egg. Length, 320–335 µm; maximum width, 235–250 µm. Ovoid outline, bowl-shaped, as usual for Campsurinae; no polar cap present.

Nymphal cuticle (last instar, male). Length (mm): body, 13.5–14.5; cerci, 9.0–10.0; terminal filament, 7.0. Head with frons almost completely covered with short and long setae (setal alveoli marked as dots in Fig. 13 ), straight anterior margin with row of long setae, two anterolateral blunt tubercles at base on antennae (larger apical one and smaller one, t in Fig. 13 ), anterior half of gena protruded and covered with long, strong setae, posterior half of gena bare, except for small area before eye also covered with long, strong setae (not shown in Fig. 13 ); inner margin of compound eye without row of setae. Pedicel 1.4× length of scape, dorsally covered with two groups of long strong setae (one group near base and another group on distal half), in-between group of slightly shorter and much thinner setae present; scape dorsally with short and strong setae; flagellum (apical portion broken off and lost) with submedian short seta on each segment. Mandibular tusk relatively long and slender, apex strongly curved inward ( Fig. 16 ); exposed area 0.5× length of head capsule; basal U-row of filtering setae present (fs in Figs. 14– 15 ); dorsal surface with numerous very long, strong setae; outer margin covered with long setae and 25–30 strong blade-like spines (increasing in size distally, bls in Fig. 16 ); inner margin with 10 small tubercles (subequal in size, except basal one slightly larger, t in Fig. 16 ), some of them alternating with short strong setae (ss in Fig. 16 ), tubercles and setae ordered in slightly curved row (in occlusal view, Fig. 14 ); ventral surface almost without setae. Maxilla (apparently hard to see in described exuviae) with small ventral gill. Thorax. Posterolateral corner of pronotum and propleura without strong setae; metasternum with few long setae. Legs. Fore legs with coxa and trochanter bare; dorsal surface of femur with outer submarginal row of long setae on distal third (arrows on Fig. 17 ), near base of outer margin with rounded projection covered by long, weak setae (rp in Fig. 17 ); base of femur and part of inner margin with row of marginal long, strong setae (st in Fig. 17 ); ventrally long U-row of filtering setae (fs in Fig. 18 ); tibia-tarsus wide, with margins subparallel, dorsal surface almost completely covered with short spines and long setae ( Fig. 17 ), ventral surface with 2 rows of filtering setae: basal W-shaped transversal row extending along ventral surface and hind margin (wr in Fig. 18 ), and double longitudinal row along anterior margin (ar in Fig. 18 ); apex of tibia-tarsus rounded, slightly projected (projection ca. 1/4 length of claw); tarsal claw slightly curved and with row of about 18 triangular denticles ( Fig. 19 ). Middle leg with coxa and trochanter with strong setae; dorsal surface of femur covered with many long setae forming mediolongitudinal group, anterior group along margin, and subdistal transversal group, hind margin bordered by much longer setae ( Fig. 20 ), ventral surface bare; tibia with anterior margin distally projected and with crown of strong spines (cs in Fig. 20 ), posterior margin completely covered with very long setae, anterior margin basally bare, distal half densely covered with thick yellowish setae; tarsus with long setae on hind margin and relatively shorter setae on apical third of fore margin; tarsal claw long and slender, slightly curved, with row of 16 denticles increasing in size distally ( Fig. 21 ). Hind leg ( Fig. 22 ) similar to middle leg, except as follows: femur with dense row of short setae on anterior margin, anterior margin of tibia with similar dense row of setae; crown of spines on tibia absent, and tarsal claw with row of 27–30 small denticles ( Fig. 23 ). Abdomen. Lateral margins of all segments with row of long setae. Terga IV–VII with mediolongitudinal row of setae. Sterna without setae. Gills. Abdominal gill I bilobed, dorsal lamella almost 3× width of ventral lamella, ventral lamella 2/3× length of anterior portion. Cercus 0.7× length of body, covered with setae dorsally and ventrally, except distal half bare. Terminal filament 0.5× length of body, thinner than cercus, covered with long scattered setae completely. Paraproct with distal sublateral spine (arrow in Fig. 24 ).

Distribution ( Fig. 178 ). Brazil (Pará orig. New records: Espírito Santo and Tocantins).

Diagnosis. Campsurus latipennis can be distinguished from all other species of the genus by the following combination of characters. In the adult: 1) posterior margin of male abdominal sternum IX convex and subtriangular, medially rounded ( Figs. 1, 3, 9 ), surface covered with microtrichiae ( Fig. 10 ); 2) pedestal bases well separated from each other, pedestals subquadrate with outer-posterior margin projected forming a short parastylus ( Figs. 2, 11 ); 3) penes separated and diverging slightly distally, each arm formed by a large and twisted sclerotized lobe, and a small ventral membranous lobe ( Figs. 1, 3, 4–6, 9, 12 ), in lateral view the main lobe presents a subapical indentation (arrows in Figs. 4–5 ); 4) medium to large size (length of male fore wings 8.4–13.5 mm); 5) female sternum VIII with anteromedian paired sockets, sockets fused with each other medially, shallow ( Figs. 7– 8 ); 6) egg without polar cap. In the nymph: 1) with small paired tubercles at base of each antennae (t in Fig. 13 ), scape and pedicel with setae; 2) pre-ocular group of setae not mounted on a tubercle; 3) mandibular tusks with apex strongly curved inwards ( Fig. 16 ), inner margin with ten tubercles of subequal size except the basal one slightly larger (t in Fig. 16 ), outer margin with 25–30 strong marginal blade-like spines and long setae ( Fig. 16 ), 10 tubercles on inner margin; 4) fore femur wide (max. width 1/2 of max. length), fore tibiae with parallel margins (rectangular in form) ( Figs. 17–18 ); 5) tarsal claws with one row of denticles (18 on fore claw, 16 on middle claw, 27–30 on hind claw) ( Figs. 19, 21, 23 ).

Discussion. Some mistakes appear in the use of the name C. latipennis . Walker (1853) described it based on male subimagos from Pará; the genitalia were later illustrated by Kimmins (1960: 313, Fig. 62 ). Eaton (1883: Plate V, Fig. 8 c) worked with imagos, obviously from a different species, collected in the same expedition by Wallace and Bates. The genitalia of the lectotype are damaged and could not be studied, but Kimmins’ (1960) figure 62 can be used to identify the species. Eaton’s (1883) imagos were not studied by us, but from his figures we identify them as C. essequibo Traver (1947) , treated below. Other authors also treated C. essequibo under the misidentification of C. latipennis ; please see the former species’ section, below, for further discussion.

Campsurus latipennis is very similar to Campsurus salobra sp. nov. and C. evanidus Needham & Murphy 1924 , but it can be separated from them because the hind margin of the styliger is medially projected but rounded (acute and triangular in C. evanidus ), the pedestal presents a slightly thinner and longer parastylus (thin but short in C. salobra , short and basally wide in C. evanidus ) and the penes present an apically twisted primary lobe and a well-developed secondary lobe (apex not twisted in the others, secondary lobe absent or reduced in C. evanidus ). Also, the penes of C. latipennis and C. evanidus , in lateral view, show an indented dorsal margin, with marked subapical concave area (arrow in Figs. 4–5 ) (smoothly convex in C. salobra sp. nov.). Campsurus cuspidatus Eaton (1871) and C. vulturorum share the distomedial projection of the hind margin of sternum IX, thus probably forming a monophyletic group. The absence of a polar cap on the egg is an autapomorphy of C. latipennis . Among the species of Campsurus , only C. evanidus presents a very small polar cap (Emmerich & Molineri 2011).

Figures

FIGURES 178. Distribution maps.

FIGURES 1 – 12. Campsurus latipennis, adult. Male imago: 1, genitalia, ventral view (v. v.); 2, details of pedestal, v. v.; 3, detail of penes and pedestals, v. v.; 4 – 5, penes, lateral view (l. v.); 6, genitalia, l. v. SEM photographs: 9, genitalia, v. v.; 10, detail of microtrichia on sternum IX; 11, pedestal, v. v.; 12, detail of penes, v. v. Female adult: 7, abdominal sternum VIII; 8, detail of sockets. Abbreviations: bp = base of penes, ml = main lobe of penes, mp = median projection of sternum IX, ps = parastylus, sl = secondary lobe of penes.

FIGURES 13 – 24. Campsurus latipennis, nymph. 13, head, d. v. (long setae omitted); 14, left mandible, d. v. (row of filtering setae indicated with dashed line); 15, right mandible, v. v. (filtering setae as in previous figure); 16, apex of right mandibular tusk; 17, foreleg, d. v. (filtering setae not shown); 18, foreleg, v. v. (only filtering setae are indicated, with dashed lines); 19, foretarsal claw; 20, middle leg, d. v.; 21, middle tarsal claw; 22, hind leg, d. v.; 23, hind tarsal claw; 24, paraprocts with spines indicated (arrow).

FIGURES 163 – 166. Male imago, general view, dorsal: 163, C. latipennis; 164, C. salobra; 165, C. essequibo; 166, C. nessimiani sp. nov. Abbreviations: ap = anteronotal projection, mps = medio parapsidal suture, ph = pronotal hump, psp = posteroscutal protuberances.

FIGURES 60 – 67. Campsurus nessimiani sp. nov., nymph: 60, head, d. v.; 61, left mandible, outer lateroventral view (showing arc of filtering setae); 62, same, oclusal view; 63, right mandible, d. v.; 64, fore leg, d. v.; 65, same, schematic, v. v.; 66, middle leg, d. v.; 67, hind leg, d. v.