Rivudiva trichobasis Lugo-Ortiz & McCafferty, 1998

Salles, F. F., Nieto, C. & Cruz, P. V., 2020, New species of Rivudiva Lugo-Ortiz & McCafferty (Ephemeroptera: Baetidae) with comments on R. minantenna Lugo-Ortiz & McCafferty and R. trichobasis Lugo-Ortiz & McCafferty, Zootaxa 4786 (1), pp. 37-52 : 49

Rivudiva trichobasis Lugo-Ortiz & McCafferty, 1998

Rivudiva trichobasis Lugo-Ortiz and McCafferty (1998: 64) ; Domínguez et al. (2006: 176); Falcão et al. (2011: 539); Cruz et al. (2011: 60) ; Boldrini et al. (2012: 93); Boldrini & Cruz (2014: 5).

Material examined. 1 nymph, Paratype (slide #270 IBN): BRAZIL, Rio Grande do Sul state, Arroio dos Vargas, S 30 o 50’ W 53 o 10’, 120 m. a.s.l., xi.1964, F Plaumann col. 7 nymphs, BRAZIL, Espírito Santo state, Linhares, Rio São José, S 19°07’33.1 W 40°14’26.1”, 24 m. a.s.l., 26.viii.2011, FF Salles leg. (4 UFVB, 3 IBN, 1 used for SEM images). 1 nymph, BRAZIL, Espírito Santo state, Afonso Cláudio, Cachoeira do Funil , S 20°08’35.1”, W 41°09’02.0’’, 440 m. a.s.l., 02.iii.2014, FC Massariol col. ( UFVB). 19°07’33.1”S/ 40°14’261”W. 1 nymph, BRA- ZIL, Espírito Santo state, Cariacica Reserva Biológica Duas Bocas, S 20°15’28.5”, W 40°29’38.3”, 210 m. a.s.l., 02.x.2013, FC Massariol col. ( UFVB) .

Diagnosis

Nymph. 1) antenna with robust, apically pointed setae on scape and pedicel ( Fig. 28 ); 2) distal margin of labrum with deep, wide, medial emargination ( Fig. 23 ); 3) dorsal surface of labrum with irregular rows of setae ( Fig. 23 ); 4) outer margin of mandibular incisors with spine-like processes ( Fig. 29 ); 5) tuft on apex of lingua formed by short simple setae (as in Fig. 14 ); 6) maxillary palp segment I of intermediate length, reaching ⅔ of apex of galea-lacinia; 7) glossa with base not expanded, apex rounded and with dorsal thick setae mostly restricted to distal margin (as in Fig. 16 ); 8) hind wing pads absent; 9) trochanter with robust, long apically pointed setae; 10) outer dorsal row, medial dorsal row and inner dorsal row robust of femora with long and apically pointed setae, those of outer row almost as long as maximum width of femur ( Fig. 33 ); 11) abdominal sterna with robust, apically pointed setae ( Figs 36–37 ); 12) paraproct with robust, apically pointed setae and 8-10 marginal spines.

Imago (according to Cruz et al. 2011). 1) dorsal portion of turbinate eyes with inner margins not parallel, divergent anteriorly (figs 1, 2 in Cruz et al. 2011); 2) length of forewing about 3.7× width (fig. 3 in Cruz et al. 2011); 3) hind wings absent; 4) segment III of abdomen with one large medially red mark near anterior margin (figs 4, 5 in Cruz et al. 2011); 5) forceps segment III oval, 2× as long as wide (fig. 6 in Cruz et al. 2011); 6) posterior margin of subgenital plate with apex concave (fig. 6 in Cruz et al. 2011).

Distribution. Paraguay and Brazil (Rio Grande do Sul, Espírito Santo, Amazonas and Roraima) ( Fig. 41 ).

Figures

FIGURE 41. Map of South America showing the distribution of the distinct species of Rivudiva.

FIGURES 22−29. Rivudiva spp. SEM photographs. (22) Labrum of R. inma, sp. nov.; (23) Labrum of R. trichobasis; (24) Maxilla of R. inma, sp. nov.; (25) Detail of crown of maxilla of R. inma, sp. nov., dorsal view; (26) Detail of crown of maxilla of R. trichobasis, lateral view; (27) Detail of crown of maxilla of R. minantenna, lateral view; (28) Scape and pedicel of R. trichobasis; (29) Outer and inner incisors of R. trichobasis. (ds, dentiseta; dc, dorsal canine; ii, inner incisor; oc, outer canine; oi, outer incisor; pe, pedicel; vc, ventral canine).

FIGURES 11−16. Rivudiva oonirikoperi, sp. nov., nymph. (11) Labrum; (12) Left mandible; (13) Right mandible; (14) Hypopharynx; (15) Maxilla; (16) Labium (left = dorsal surface, right = ventral surface).

FIGURES 30−37. Rivudiva spp. SEM photographs. (30) Fore femur of R. inma, sp. nov.; (31) Fore femur of R. inma, sp. nov., detail of outer margin; (32) Femur of R. minantenna; (33) Femur of R. trichobasis; (34) Tarsal claw of R. inma, sp. nov., inner view; (35) Tarsal claw of R. minantenna, lateral view; (36) Abdominal sternum of R. trichobasis; (37) Abdominal sternum of R. trichobasis, detail of setae.