Campsurus violaceus Needham & Murphy

Molineri, C., Salles, F. F. & Emmerich, D., 2015, Revision of Campsurus violaceus species group (Ephemeroptera: Polymitarcyidae) with new synonymies and nomina dubia in Campsurus Eaton, 1868, Zootaxa 3920 (1), pp. 51-68 : 54-61

Campsurus violaceus Needham & Murphy

( Figs. 1−3 , 5−11 , 12−27 , 41−43 )

Campsurus violaceus Needham & Murphy, 1924: 18 ; Traver, 1947: 379; Domínguez et al. 2006: 580. Campsurus meyeri Navás, 1934: 24 ; Traver, 1947: 371; Domínguez et al 2006: 576 NEW SYNONYM Campsurus notatus Needham & Murphy, 1924: 20 ; Navás, 1926: 109; Traver, 1944: 39; Traver, 1947: 382; Demoulin, 1955:

30; Irmler, 1975: 348; Domínguez et al. 2006: 576 NEW SYNONYM

Campsurus paranensis Navás, 1932: 111 ; Domínguez et al 2006: 577 NEW SYNONYM

Type material. C. meyeri : 3 dried male imagos (in vial, not pinned), in good condition, accompanied by two labels: " Campsurus meyerii Long. Navás " (tipping-machine) and "nº 36958" (hand-written), without locality data. We rehydrated one male, dissected and mounted the genitalia, the body is preserved in ethyl alcohol. There is no indication in the vial that these specimens are types, and no collection data is present. The size and general aspect coincide with original description. Deposited in MACN.

C. violaceus : Holotype slides of male imago, one with two pairs of wings and the other with genitalia, both with a red small label and a white larger one that indicate: " Holotype Cornell U. No. 620" and "Cornell University No. 654, SUB. 4, SL♂, Campsurus violaceus, Date. Santa Fe Arg", respectively. Allotype slide with a pair of wings of a female adult, bearing two labels: a partially damaged small red one "Allotype, Cornell U., 620.2" and a larger white label including the following information: "Cornell University No. 654, SUB. 4, SL♀, Campsurus violaceus, Date. Santa Fe Arg". Deposited at CUIC.

Campsurus notatus holotype male imago slide with genitalia and a pair of wings bearing a white label with a small red label glued above: " Holotype Cornell U. No. 624.1" (red label) and Cornell University, SL♂, Campsurus notatus , Paraguay R. Brazil ". Paratype male imago slides with a pair of wings and genitalia with two white labels with similar information except additional locality data: Paraguay R., above Porto Esperança, Brazil, and " Paratype Cornell U. No. 624".

Campsurus paranensis : 1 male imago, pinned, in good condition, from ARGENTINA: Santa Fé, 7.i.1927, Bridarolli. Deposited in IBIGEO.

Additional material. ARGENTINA: 2 male imagos, pinned, in good condition, from Delta Río Chana, Col. E.E. Blanchard ( MACN); 2 male imagos, pinned, in good condition, one of them bearing a red-bordered handwritten label " Campsurus holmbergi Weyh. " and a white label indicating "Rep. Argentina, Prov. de Bs As, 189, C. Bruch". The other specimen, with the subimaginal exuvia still attached to the cerci, bear the same information but in white labels (both in MACN); 23 nymphs, 2 reared male and 1 reared female adults from Corrientes, Esteros del Iberá, Colonia Pellegrini, x.2004, P. Pessaq col. (these nymphs were used for the description, drawings and pictures below); 36 male and 4 female adults (male parts on slides IBN70CM and IBN296CM, female IBN297CM) from Santa Fé, Santo Tomé, Salado river, nuptial flight (20 hs), 19.iv.1998, C. Molineri col.; 1 reared male (slide IBN647CM) from Santa Fé, Santo Tomé, Salado river, 14.iv.1997, F. Zilli col.; 20 male and 1 female adults from Corrientes, Mburucuyá National Park, Casco Central Estancia, light trap, 12−14.xii.1999, C. Molineri col.; 3 male imagos from Tucumán, Burruyacu, 3.xi.2008, M.J. Barrionuevo col.; 12 male and 25 female adults from Tucumán, Simoca, Bañados de Monteagudo, 27.iii.1997, light trap (21 hs), C. Molineri col.; 8 male and 12 female adults ( IFML) from Santiago del Estero, Colonia Dora, 25.i.1983, A. Willink col.; 22 female adults from Córdoba, Yacanto de San Javier, 14.i.1982, E. Domínguez col.; 30 female adults from Santa Fe, Esperanza, town, light trap (20 hs), 12.iv.1998, C. Molineri col.; 10 male and 3 female adults from Formosa, near Ibarreta, 18.xi.1981, E. Domínguez col.; 6 male and 2 female adults from Formosa, 10 km South from Formosa, Torhue stream, 8.xii.1986, E. Domínguez col.; 12 male and 1 female adults from Santiago del Estero, Dpto. Figueroa, Caspi Corral, 27.xii.1982, E. Lavilla col.; 10 male and 2 female adults ( IFML) from Tucumán, La Cocha, Los Pizarro dam, 10−13.xii.1982, R. Golbach col.; 4 male and 7 female adults from Santiago del Estero, Las Termas, Dique Frontal, 2.x.1981, E. Domínguez col.; 11 female adults from Misiones, 10 km NE from San Vicente, INTA Cuartel Victoria, 20.xi.1998, Domínguez, Molineri & Nieto cols.

BOLIVIA: 1 male imago from Cochabamba, río Ichilo floodplain lake, S 16º 4' 45" – W 64º 44' 20", E. Goitía col.

BRAZIL: 6 male imagos from Mato Grosso do Sul, Baia river, light trap, vi.2005, Sandra M. Melo col.; 2 male imagos from Guaraná lake, 28.xii.1997, aprox. S 22° 43' 26" – W 53º 18' 3" ( CZNC); 1 male imago, 1 terminalia male imago (body missing) and 10 female adults from Mato Grosso, Transpantaneira rute, Porto Jofre, light trap, 6.v.1984, aprox. 17º 21' 46"–56º 46' 42", B. M. Mascarenhas et al. cols. ( CZNC); 5 male imagos from Patos lake, 22.iv.1998, aprox. 22º 43' 12"–53º 17' 37" ( CZNC); 23 male imagos from Amazonas, floodplain lake, 16−17.ix.2003, UV light trap, aprox S 3º 39' 29" – W 61º 29' 28" ( CZNC); 2 male imagos from Brazil, Piauí, 01.vi.2011, Domingos Mourão, Vila Cachoeirinha, road to Domingos Mourão, S 4 º 10' 6" – W 41º 34' 55", P. V. Cruz Col. ( CZNC).

COLOMBIA-PERU border: 1 male imago from Amazonas, Rondiña Island, S 4º 08' 23" – W 69º 59' 12", 9−10.ii.1999; M.C. Zúñiga & C. Molineri col (IBN). COLOMBIA: 1 male and 1 female imagos from Amazonas, Puerto Nariño, Loreto Yacu, 5.ii.1999, light trap 18−20 hs, E. Domínguez, M.C.Zúñiga & C. Molineri cols. (IBN); 6 male and 2 female adults same data except Tarapoto lake, 4.ii.1999 (MUSENUV); 2 male imagos from Amazonas, Natural Reserve Palmarí, Yabarí river, administration center, 120 m, 29.v.2002, light trap, S 4º 17' 10" – W 70º 17' 49", Zúñiga, Emmerich, Cardozo-Zúñiga AJ, Cardozo-Zúñiga RJ (MUSENUV); 1 male and 1 female adults (sternum VIII and eggs for SEM dissected from this female) Valle del Cauca, Ríofrío, Riofrío river, 5 km before Salónica, light trap 18−21 hs, N 4º 7' 39" − W 76º 22' 6", 1150 m, 22.ix.2002, Zúñiga, Ballesteros, Cardozo & Cardona cols. (IBN).

URUGUAY: 3 male imagos, Salto, Paso Yacaré, Itapebí stream, 9.i.1978, 21−22hs, Zolessi, Morelli & Rodríguez cols. (FCE-Ep); 8 male imagos and 7 females imagos, Maldonado, rute nº 12, km 9, “La Chacra”, Laguna del Sauce, 23.xii.2002, ligth trap, D. Emmerich col. (IBN); 43 male imagos and 30 female imagos, Rivera, Santa Ernestina, rute nº 29, stream near Mina Corrales, S 31º 32' 23.8" − W 55º 33' 42", 146 m, 10.xi.2008, ligth trap, D. Emmerich col. (IBN); 7 female imagos, Lavalleja, Camping Arequita, Santa Lucía river, S 34° 17' 06" − W 55° 17' 02", 123 m, 3.iii.2008, ligth trap, D. Emmerich & S. Pérez cols. (IBN); 2 male imagos and 7 female imagos, Maldonado, rute nº 60 (km 23), El Rodeo stream, S 34° 40' 20" − W 55° 14' 15", 75 m, 7.xi.2008, ligth trap, D. Emmerich & S. Pérez cols. (FCE-Ep); 3 male imagos and 16 female imagos, Treinta y Tres, Quebrada de los Cuervos, Yerbal Chico stream, S 32º 55' 35.2" − W 54º 27' 39.6", 78 m, 25.iii.2010; ligth trap, D. Emmerich & C. Molineri cols. (FCE-Ep); 52 male imagos and 53 female imagos, Rocha, rute nº 15, Km 10, La Paloma, La Palma stream, S 34º 35' 10.6" − W 54º 10' 43.1", 5 m, 22.iii.2010, ligth trap, D. Emmerich & C. Molineri cols. (IBN).

Distribution. Argentina, Bolivia, Brasil, Uruguay, Paraguay, Colombia, Peru.

Diagnosis. Campsurus violaceus can be separated from the other species of the violaceus species group by the following combination of characters: 1) pedestals elongate, with the outer corner slightly projected ( Fig. 1−3 , 5−8, 11 ); 2) penes relatively slender, with rounded "thumb" ("t" in Fig. 1−3 , 5−6, 11 ); 3) female sternum VIII with relatively wide and short anterior furrow ("f" in Fig. 42 ) and single socket ( Figs. 41−42 ). Eggs are not distinguishable from other species in the violaceus group. One character may be useful to distinguish nymphs of C. violaceus from C. truncatus , but this should be confirmed with the study of more material of the last species: in C.

violaceus nymphs, the row of denticles on the inner margin of mandibular tusks is formed by 6−11 denticles that increase in size basally, except the most basal one that is as least three times larger than the previous one ( Figs. 12−15 ); between each one of these denticles a stout seta is present ( Figs. 14−15 ).

Male imago. Length (mm): body, 10.5−11.7; FW, 10.3−12.0; HW, 4.4−5.4; cerci, 29.0; foreleg, 5.0. Foreleg, ratio of segments in relation to femur (1.38 mm): femur (1), tibia (0.9−1.0), tarsomere 1 (0.1); tarsomere 2 (0.3−0.4); tarsomere 3 (0.4), tarsomere 4 (0.4), tarsomere 5 (0.4), short claw (0.2), long claw (0.3). Tarsal segments 2−4 subequal, slightly shorter than 5 (the longest), tarsomere 1 very short. Genitalia ( Fig. 1−3 , 5−11 ): sternum IX subtriangular with apical margin straight to slightly concave; pedestal slender, slightly flattened dorsoventrally, distally with large rounded inner corner ("ip" in Fig. 3 ) and short outer corner generally blunt ("op" in Fig. 3 ); forceps long and slender distally widened; penes finger-like, curved and ventrally directed, becoming thinner toward the rounded apex, "thumb" relatively well developed and rounded ("t" in Fig. 3 ).

Female imago. Length (mm): body, 14.0−19.0; FW, 13.6−16.0; HW, 5.5−7.0; cerci, 4.0−5.0. Forelegs generally present but one or both may be lost during the molt from nymph to subimago. Sternum VIII with anterior furrow relatively short and wide, and anterior single socket as in Figs. 41−42 ; sternum completely covered by microtrichia, except anteriorly and around the socket.

Egg. Length (µm), 210−220; width, 120−130. Ovate (ratio L/W: 1.7−1.8), with a strong concavity as in Fig. 43 ; the capped pole is slightly wider than the uncapped pole ( Fig. 43 ). Polar cap of Type III ( Koss & Edmunds 1974) formed by 12−15 very long filaments twisted around and coiled forming a subcircular cap ( Fig. 43 ). Chorionic surface relatively smooth, very small grooves may be present on concave area ( Fig. 43 ).

Mature nymph. Length of male (mm): body, 14.8−16.2; terminal filament, 7.0−8.0; cerci, 9.0−10.5. Length of female (mm): body, 16.0−19.5; terminal filament, 7.0−7.5; cerci, 6.0−7.0. General coloration whitish yellow with purplish gray shading dorsally. Head ( Fig. 21 ) shaded grayish dorsally, except on whitish genae and yellowish frontal projection; darker between lateral ocelli, pigments forming a netted pattern on occipital area. Head capsule with rows of long setae on inner margin of eyes and lateral ocelli, on lateral edge of genae just anteriorly to eyes, and on anterior margin of frons ( Fig. 21 ); a large area anterior to epicranial suture densely covered with shorter setae, a thin transverse band anterior to ocelli is smoother (with less setae or without setae at all, glabrous band "gb" in Fig. 21 ). Antennae whitish, the head is slightly elevated at the base of antennae and a strong spine-like projection is present on foremargin of frons, arising also as part of this elevated antennal base; pedicel twice as long as scape, scape with few setae dorsally, pedicel with many setae dorsally as in Fig. 21 . Mouthparts whitish except sclerotized areas, spines and thick setae yellowish. Labrum subquadrate, small, covered with setae dorsally; clypeus with straight anterior margin. Mandibles with reduced 3-pointed outer incisor and 2-pointed movable incisor; ventrally with a double row of long filtering setae at base; distally with large and slender 1-pointed mandibular tusks. Mandibular tusks ( Figs. 12−15 ) with a row of pointed denticles, the most basal one (or subbasal tubercle, "st" in Fig. 12 ) is larger (ca. 3x) than the others ("d" in Fig. 13 ); intercalated between each of these denticles a single stout seta is present; the number of denticles presents some variation (6−11 in each tusk) but is the same (or differ only by 1 or 2) in both mandibles. Tusks are covered by long simple setae, mainly on dorsum and outer margin; also on outer margin a row of short stout spine-like setae are present ("s" in Fig. 15 ). Maxillae with a subtriangular membranous gill at the base ("bg" in Figs. 18−19 ); apex of galea-lacinia thin and pointed, apex and inner margin covered with long setae; palpus with long setae on outer margin, and with a dense patch of setae on inner margin of palp segment 2. Hypopharinx with pointed lingua and rounded superlingua with setae distally ( Figs. 16−17 ). Labium with pointed paraglossae, covered by numerous setae ( Fig. 20 ). Thorax yellowish white shaded gray on pronotum and mesoscutum, darker on carinae. Wingbuds whitish shaded purplish gray to brownish along costal margin. Thoracic pleura and sterna without marks. Legs whitish except at joinings, yellowish. Forelegs with numerous fringed setae forming a basal group on femur ("br" in Figs. 23−24 ) and two double rows on tibio-tarsus ("ir" and "vor" in Fig. 23 ); suture between foretibia and tarsus not visible, apex with two points; middle legs ( Fig. 25 ) and hind legs ( Fig. 26 ) with long and short simple setae, and areas densely covered by short setae on inner margin of tibiae II −III and of femur III; all tarsal claws long and slender without denticles. Abdomen yellowish white shaded widely with purplish gray dorsally except pale transverse dash at each side of terga II −VI and paired smaller pale spots on VII −IX; terga VIII −IX with thin black mediolongitudinal line. Abdominal sterna paler, not shaded, or only slightly shaded on median zone of sterna; sterna with scattered long setae, on VIII more numerous around the anterior half of the mediolongitudinal axis ( Fig. 22 ); short setae present on the paired protuberances bordering the anus ( Fig. 22 ). Gills: vestigial gill I whitish, bilamellate with a short and thin ventral lobe and a larger rounded dorsal lobe ( Fig. 27 ); gills 2−7 with ventral lobe slightly shorter than dorsal lobe but increasing in length posteriorly, so on gill 7 both lobes are subequal in length; lamellae and fringes of gills whitish completely shaded with light grayish purple. Caudal filaments whitish covered with thin yellowish setae.

Discussion. Type of Campsurus violaceus Needham & Murphy (1924) presents pedestals with a characteristic form ( Figs. 1 and 5 ), a truncate to slightly concave hind margin of male sternum IX, finger-like penes with a roundish inner ventral protuberance at base (thumb), and an outer subtriangular outgrowth of the pyramidal base (pb in Fig. 3 ). These characters are present in the same form in other types of Campsurus that we are considering as subjective junior synonyms: C. notatus Needham & Murphy ( Figs. 3 , 6−7 ), C. meyeri Navás ( Figs. 2 , 8−9 ), and C. paranensis Navás ( Figs. 10−11 ).

Nymphal description given above is, to our knowledge, the first formal description for the species. Reared nymphs from Iberá ( Argentina, Corrientes) were used for descriptions and illustrations. The nymphs of C. violaceus are almost undistinguishable to C. truncatus (described by Pereira & Da Silva 1991 under C. melanocephalus ), but see diagnosis for further comments. Both species are similar to the nymphs of C. major and C. argentinus ( Molineri & Emmerich 2010) , only differing because femora II −III present less developed setation on dorsum than major-argentinus. Nevertheless, microhabitat of both groups are completely different: the nymphs of violaceus group burrow tunnels in soft mud at the bottom of lakes or river pools, while nymphs of the major group live in silk cases above rocks in river pools ( Molineri & Emmerich 2010).

Figures

FIGURES 1 − 4. Photographs of male genitalia (types): 1, C. violaceus holotype slide (CUIC); 2, C. meyeri paratype (rehydrated and mounted on slide MACN); 3, C. notatus holotype slide (CUIC); 4, C. truncatus paratypoid (pinned, ZMH). Abbreviations: ip = inner projection (pedestal); op = outer projection (pedestal); p = penes; pb = pyramidal base (penes); t = ” thumb ” (penes).

FIGURES 5 − 11. Male genitalia (types): 5, C. violaceus, v. v. (holotype); 6, C. notatus, v. v. (holotype); 7, C. notatus, v. v. (paratype); 8, C. meyeri, v. v. (holotype?); 9, same, lateral view; 10, C. paranensis, l. v. (holotype); 11, same, v. v. Abbreviations: dpa = dorsal portion of penean arm; pb = pyramidal base (penes); pj = pedestal joint; vpa = ventral portion of penean arm.

FIGURES 12 − 20. C. violaceus, mouthparts: 12 − 13, photographs of mandibular tusks (different specimens from Santa Fé, showing morphological variations), dorsal view; 14 − 15, mandibular tusks, d. v. (basal U-row of filtering setae omitted); 16 − 17, hypopharynx, ventral and lateral view; 18 − 19, maxilla, ventral and oclusal view; 20, labium, lateral view. Abbreviations: bg = basal gill; d = denticles; st = subbasal tubercle; s = stout spine-like setae.

FIGURES 21 − 27. C. violaceus, nymph. 21, head, d. v.; 22, abdominal sterna IX − X; 23, fore leg, v. v.; 24, same, d. v.; 25, middle leg, d. v.; 26, hind leg, d. v.; 27, gill I. Abbreviations: br = basal row (femoral filtering setae, most setae omitted); gb = glabrous band; ir = inner double row (filtering setae, tibia); vor = ventral-outer double row (filtering setae, tibia); s = spine of paraproct.

FIGURES 41 − 46. Female sternum VIII and eggs. C. violaceus: 41, sternum VIII (s = socket); 42, detail of socket; 43, egg. C. decoloratus: 44, eggs; 45, sternum VIII; 46, detail of socket. Abbreviations: f = furrow; r = rib; s = socket.