Callibaetis (Callibaetis) molinerii, Cruz, Paulo Vilela, Salles, Frederico Falcão & Hamada, Neusa, 2017

Cruz, Paulo Vilela, Salles, Frederico Falcão & Hamada, Neusa, 2017, Four new species of Callibaetis Eaton (Ephemeroptera: Baetidae), nymphal description of Callibaetis (Abaetetuba) fasciatus (Pictet) and keys for South American species of Callibaetis, Zootaxa 4250 (3), pp. 229-261 : 246-251

Callibaetis (Callibaetis) molinerii sp. nov.

( Figs 13–16 )

Callibaetis sp. D: Cruz et al. 2016

Known stages. Male and female imagoes, nymph

Diagnoses. Male imago: 1) dorsal portion of turbinate eyes oval ( Fig. 13 A); 2) dorsal portion of turbinate eyes, in lateral view, without constriction ( Fig. 13 B); 3) turbinate portion of compound eyes (in lateral view) with divergent anterior and posterior margins ( Fig. 13 B); 4) forewing hyaline ( Fig. 13 G); 5) marginal intercalary veins paired ( Fig. 13 G); 6) hind wing hyaline ( Fig. 13 H); 7) hind wing with a rounded costal process ( Fig. 13 H); 8) marginal intercalary vein on hind wing present ( Fig. 13 H); 9) surface of abdominal sterna covered with brown spots ( Fig. 13 C); 10) abdominal sterna with pigmented medioanterior and medioposterior sigilla ( Fig. 13 C); 11) segment I of forceps wide at base ( Fig. 13 K); 12) segment III of forceps with truncated apex ( Fig. 13 K).

Female imago: 1) forewing brown, except basal third ( Fig. 13 I); 2) paired marginal intercalary veins ( Fig. 13 I); 3) hind wing with basal brown mark ( Fig. 13 J); 4) hind wing with a rounded costal process ( Fig. 13 J); 5) marginal intercalary veins on hind wing absent ( Fig. 13 J); 6) abdominal terga and sterna covered with brown spots ( Figs 13 D–F); 7) abdominal sterna with pigmented medioanterior and medioposterior sigilla ( Fig. 13 F); 8) absence of oblique marks on abdominal terga III, V and VII.

Mature nymph: 1) maxillary palp 1.5× length of galea-lacinia ( Fig. 14 E); 2) maxilla with tuft of stout setae on outer margin proximad of palp insertion ( Fig. 14 E); 3) paraglossae without row of stout setae on ventral surface ( Fig. 14 G); 4) segment III of labial palp rounded apically ( Fig. 14 G); 5) metanotum without spines; 6) anterior surface of fore tarsus with stout setae ( Fig. 15 C).

Description. Male Imago. Length: body, 6.6 mm; forewing, 6.2 mm; hind wing, 1.1 mm; tibiae, 1.8 mm (n=2). Head ( Fig. 13 A) brown. Turbinate portion of compound eyes dorsally yellowish brown, stalk yellowish white. Antenna with scape, pedicel and flagellum brown apically. Dorsal portion of turbinate eyes oval; inner margins parallel. Thorax with anteronotal protuberance, posterior scutal protuberance and scutellum brown. Anteronotal and metascutellar protuberance rounded. Femora with brown spots on posterior surface; tibiae, on ventral margin, with brown mark basally and apically; tarsi brown. Tibia I 1.3× length of femur I; tarsus I 1.3× length of femur I. Forewing hyaline ( Fig. 13 G); veins light brown; stigmatic area with six cross veins not reaching the subcostal vein; marginal intercalary veins paired; length of each intercalary vein 0.2× or less the distance between adjacent longitudinal veins; length of forewing about 2.5× its width. Hind wing hyaline, with five to seven cross veins ( Fig. 13 H); costal process rounded; marginal intercalary vein present. Abdomen with few spots on terga ( Fig. 13 A). Sterna covered with brown spots; medioanterior and medioposterior sigilla pigmented ( Fig. 13 C). Segment I of forceps ( Fig. 13 K) wide at base, 0.25× length of segment II; distance between base of forceps 0.2× distance between lateral margins of forceps; segment III of forceps truncated apically, length 0.9× width; 0.1× length of segment II. Posterior margin of styliger plate with small rounded medial projection. Cerci lost.

Female imago. Length: body, 6.2 mm; forewing, 6.6 mm; hind wing, 1.0 mm (n=2). Head ( Fig. 13 D) light brown, with four brown marks; compound eyes black. Antenna with apically brown scape and pedicel. Thorax with anteronotal protuberance light brown; posterior scutal protuberance brown. Anteronotal and metascutellar protuberance rounded. Femora with brown spots on anterior surface; tibiae with basal, medial and apical brown mark. Forewing brown, except on basal third ( Fig. 13 I); veins brown; stigmatic area with 4–6 cross veins reaching the subcostal vein and 1–2 veins which does not; marginal intercalary veins paired, except between ICuP and A; length of each intercalary vein 0.3× or less distance between adjacent longitudinal veins; length of forewing about 2.5× its width. Hind wing hyaline, with brown mark basally ( Fig. 13 J); costal process rounded; marginal intercalary veins absent. Abdomen with terga and sterna covered with brown spots ( Figs 13 D – 13F); abdominal sterna with pigmented medioanterior and medioposterior sigilla ( Fig. 13 F). Cerci lost.

Mature nymph. Length: body, 6.8 mm; cerci, 3.0 mm; paracercus, 2.7 mm (n=2) Head brown. Turbinate portion of male compound eyes yellowish brown. Antenna with spines and thin setae on flagellum ( Fig. 14 A). Labrum ( Fig. 14 B) maximum length about 1.3× minimum length; anterolateral margins with long and stout setae; distal margin with stout setae medially; dorsal surface with numerous long and thin setae; distal margin without setae ventrally; ventral surface with short and stout setae near lateral and anterolateral margin. Right mandible ( Fig. 14 C) with 4+3 denticles; margin between prostheca and mola straight; basal half with short, thin setae and pores scattered over dorsal surface. Left mandible ( Fig. 14 D) with 4+3 denticles; margin between prostheca and mola straight; basal half with short, thin setae and pores scattered over dorsal surface. Lingua of hypopharynx ( Fig. 14 F) with lobe covered with simple setae; short and thin setae scattered over inner margin of superlingua. Maxilla ( Fig. 14 E) medially, on inner margin, with 1+4 stout setae; with tuft of stout setae on outer margin proximad of palp insertion. Maxillary palp 1.5× length of galea-lacinia; palp segment II as long as segment I; outer margin of segment I covered with long and thin setae; inner and outer margin of segment I with short and stout setae; inner margin of segment II with one row of stout setae. Labium ( Fig. 14 G) with glossae shorter than paraglossae, inner margin of glossae with 11 stout setae; apex with one small and stout setae; outer margin with one row of long and stout setae; dorsal surface with one oblique tuft of long and stout setae and one tuft of small setae near outer margin. Dorsal surface of paraglossae with one longitudinal row of long stout setae near inner margin, one longitudinal row of long and stout setae at middle, covered with long and stout setae near outer margin; ventral surface without a row of stout setae. Labial palp with segment I 1.1× length of segments II and III combined; inner and outer margin of segment I with one row of stout setae; ventral surface of segment I with stout setae; inner margin of segment II with eight short and stout setae; dorsally with one row of eight short and stout setae; segment III with rounded apex, whole margin of segment III with stout setae. Thorax brown. Metanotum without spines. Foreleg ratio ( Fig. 15 A) 1.7:(0.9 mm):0.8:0.3. Forefemur length about 4.7× maximum width; dorsal margin with row of stout setae; length of setae on dorsal margin about 0.17× maximum width of femur; ventral margin with few short and stout setae; anterior surface, near dorsal margin, with one row of stout setae; anterior surface, near ventral margin with one row of trifid and stout setae on basal half, and one row of short, simple and stout setae on distal half. Ventral margin of tibia with one row of stout setae; anterior surface with one row of stout setae. Ventral margin of tarsus with two rows of setae, one stout and other short, trifid and stout ( Fig. 15 F); anterior surface with stout setae. Claw 0.3× length of tarsus ( Fig. 15 D). Mid and hind legs ( Fig. 15 E) with anterior surface of femora with stout setae near dorsal and ventral margins; anterior surface of tibiae covered with pectinate stout setae; tarsi with pectinate stout setae on ventral margin and anterior surface. Mid and hind claws with smaller denticles ( Fig. 15 E). Abdomen ( Fig. 16 A) light brown. Posterior margin of terga with regular spines ( Fig. 16 B). Surface of sterna covered with thin setae. Gill I subequal to length of segment II, with three folds. Gill IV equal to length of segments V and VI combined, with two folds. Gill VII equal to the length of segment VIII and half of segment IX combined, with one fold. Paraproct with ca. 34 marginal spines ( Fig. 16 C). Paracercus and cerci with long spines on all segments on apical half ( Fig. 16 F); basal half with long spines every two segments ( Figs 16 D, 16E).

Comments. The nymph of C. (Callibaetis) molinerii sp. nov. is similar to the nymph of C. (Callibaetis) cruentus Cruz, Salles & Hamada , and can be distinguished by the presence of tuft of stout setae on outer margin proximad of maxillary palp insertion in C. (Callibaetis) molinerii sp. nov.

Etymology. The name of this species is in honour of Dr. Carlos Molineri, for his significant contributions to the knowledge of the Ephemeroptera in South America.

Material examined. Holotype: one nymph, COLOMBIA, Caldas, Neira, afluente do Rio Tapia , Tareas , 19.vii.2011, corredeira, C. Molineri coll., INPA . Paratypes: three female imagoes reared, five male imagoes reared, two male subimagoes reared, two female subimagoes reared, seven nymphs, COLOMBIA, Caldas, Neira, afluente do Rio Tapia, Tareas , 19.vii.2011, corredeira, C. Molineri coll., INPA .

Distribution. Colombia: Caldas.

Figures

FIGURE 13. Callibaetis (Callibaetis) molinerii sp. nov. imagoes. A. dorsal view of male; B. lateral view of male; C. ventral view of male; D. dorsal view of female; E. lateral view of female; F. ventral view of female; G. forewing of male; H. hind wing of male; I. forewing of female; J. hind wing of female; K. genitalia. Black arrow: marginal intercalary vein.

FIGURE 14. Callibaetis (Callibaetis) molinerii sp. nov. nymph. A. antenna; B. labrum (left v. v., right d. v.); C. right mandible; D. left mandible; E. maxilla; F. hypopharynx; G. labium (left v. v., right d. v.).

FIGURE 15. Callibaetis (Callibaetis) molinerii sp. nov. nymph. A. foreleg; B. detail of anterior surface near ventral margin; C. details of tarsus near ventral margin; D. detail of foreclaw; E. detail of hind claw; F. detail of the trifid setae on foretarsus.

FIGURE 16. Callibaetis (Callibaetis) molinerii sp. nov. nymph. A. dorsal view of nymphal exuviae; B. posterior margin of terga IV; C. paraproct; D. basal half of cercus; E. apical half of cercus; F. paracercus.