Camelobaetidius baumgardneri, Boldrini, R. & Pes, A. M. O., 2014

Boldrini, R. & Pes, A. M. O., 2014, Five new species of Camelobaetidius Demoulin, 1966 (Ephemeroptera: Baetidae), and redescription of Camelobaetidius mexicanus (Traver & Edmunds, 1968), Zootaxa 3796 (3), pp. 545-567 : 546-551

Camelobaetidius baumgardneri sp. nov. Boldrini

( Figs. 1 ; 8–17)

Diagnose. Nymphs: 1) Labrum subrectangular ( Fig. 8 ); 2) segment II of labial palp with distomedial projection triangular with apex pointed ( Fig.13 ); 3) thoracic gill absent at the base of coxae; 4) tarsal claws with 49–55denticles ( Fig. 14 ); 5) posterior margin of terga with rounded spines ( Fig. 15 ).

Description. Nymph. Length of body: 4.8–5.5 mm; length of antennae: 1.2–1.4 mm; length of cerci: 2.1 mm; length of terminal filament: 1.8–2.0 mm; tibia I: 0.8 mm; tibia II: 0.8 mm; tibia III: 0.6 mm.

Head ( Fig. 1 ). Light brown. Antennae light brown. Lateral branch of epicranial suture straight.

Labrum ( Fig. 8 ). Subrectangular, broader than long. Length about 0.6× maximum width; lateral and anterolateral margin with long, fine, bifid and pectinate setae; medially with fine, bifid and pectinate setae. Dorsally with five short, fine, simple setae scattered over basal area; dorsolateral arc of setae with a row of 1 + 7 long, fine, apically pointed setae.

Left mandible ( Fig. 9 ). Incisors with seven denticles. Prostheca robust, apically denticulate. Margin between prostheca and mola with two spine-like setae; subtriangular process narrow; setae at apex of mola absent. Basal half with four short, fine, simple setae.

Right mandible ( Fig. 10 ). Incisors with seven denticles. Prostheca slender, apically with longitudinal row of denticles; margin between prostheca and mola with three spine-like setae; setae at apex of mola present. Basal half with four short, fine, simple setae.

Hypopharynx ( Fig. 11 ). Lingua shorter than superlingua; apex rounded, with tuft of short, fine, simple setae. Superlingua not expanded, with fine, simple setae scattered over lateral and distal margin.

Maxilla ( Fig. 12 ). Inner dorsal row of setae with two pectinate denti-setae, apical denti-seta opposed to canines. Medial protuberance of galea with 1 + 3 long, fine and simple setae. Maxillary palp 1.2× length of galealacinia. Fine and simple setae present at apex of segment I of maxillary palp.

Labium ( Fig. 13 ). Glossa shorter than paraglossa; inner margin with six spine-like setae increasing in length distally; apex with two long, spine-like setae; outer margin with two long, spine-like setae; ventral and dorsal surface bare. Paraglossa sub-rectangular, curved inward; apex with two rows of long, fine, simple setae; ventral surface bare; dorsal surface with three fine, spine-like setae near to apex. Labial palp segment II with distomedial projection triangular with apex pointed; dorsally with a row of four fine, spine-like setae; segment III rounded, length 0.5× width, scattered with spine-like setae.

Thorax ( Fig. 1 ). Light brown. Hind wing pad present. Thoracic gill absent at the base of coxae. Femur, tibia and tarsi light brown; apex of femur brown. Tibia I 1.1× length of femur I, tibia II 0.9× length of femur II, tibia III 0.8× length of femur III; tarsi I 0.5× length of femur I, tarsi II and III about 0.4× length of the respective femur.

Forefemur ( Fig. 14 ). Length about 2.7× maximum width; dorsally with row of c.a. 50 long, spine-like setae; ventrally with three short spine-like setae. Foretibia. Dorsally with fine, simple setae; ventrally with few fine, simple setae; anterior surface with three short spine-like setae, apex with two spine-like setae; patella-tibial suture present, 0.5× length of tibia. Foretarsi. Ventrally with five short, spine-like setae. Tarsal claws with 49–55 denticles. Mid femur. Length about 3.2× maximum width; dorsally with row of c.a. 55 long, spine-like setae. Hind femur. Length about 3.2× maximum width; dorsally with row of c.a. 40 long, spine-like setae.

Abdomen ( Fig. 1 ). Light brown, except for brown anterolateral oblique stripe on segments II to VI and anterior and posterior sigilla. Terga with creased surface, posterior margin of tergum IV with rounded spines ( Fig. 15 ). Gills oval. Gills IV ( Fig. 16 ) light brown; margins with narrow spine intercalating short, fine, simple setae; tracheae pigmented. Gill I 0.6× length of segment II; gill IV 2.0× length of segment V; gill VII 0.8× length of segment VIII. Paraproct ( Fig. 17 ). With three spines near inner margin; without shagreened area; postero-lateral extension with marginal spines. Cerci light brown; outer and inner margin of terminal filament and inner margin of the cerci with tufts of long, simple setae; outer margin of the cerci with spines at apex on each segment.

Etymology: The name of the species is in honor of Dr. David E. Baumgardner, for his significant contributions to the knowledge of Ephemeroptera .

Distribution. BRAZIL: Goiás.

Comments. The nymphs of Camelobaetidius baumgardneri sp. nov. are possibly closely related to C. sallesi sp. nov. Both species present the unique combination of characteristics such as the segment II of labial palp with distomedial projection triangular with apex pointed, thoracic gill absent at base of forecoxa, tarsal claws with similar number of denticles, and terminal filament as long as cerci. Camelobaetidius baumgardneri is easily distinguished from C. sallesi sp. nov. by the shape of labrum, subrectangular ( Fig. 8 ) in C. baumgardneri sp. nov., and narrowly rounded anteriorly ( Fig. 38 ) in C. sallesi sp. nov., and by the shape of the spines on posterior margin of terga IV, rounded in C. baumgardneri sp. nov. ( Fig. 15 ), and pointed ( Fig. 45 ) in C. sallesi sp. nov..

Material examined. Holotype: Nymph, BRAZIL, Goiás, Posse, Rio do Prata, 14°14'46.4"N / 46°33'07.0"W, 09.viii.2010, Boldrini, R., Hamada, N. and Querino, R. leg ( INPA). Paratypes: Two nymphs, same data as holotype ( CZNC). Two nymphs (mounted on slides, medium Euparal), same data as holotype ( UFRR).

Figures

FIGURES 1 – 4. Camelobaetidius, nymphs (d. v.). 1, C. baumgardneri sp. nov. 2, C. carolinae sp. nov. 3, C. cruzi sp. nov. 4, C. matilei.

FIGURES 5 – 8. 5, C. sallesi sp. nov. 6, C. tepequensis sp. nov. 7, C. mexicanus.

FIGURES 8 – 13. Camelobaetidius baumgardneri sp. nov., nymph. 8, labrum (left v. v., right d. v.). 9, left mandible. 10, right mandible. 11, hypopharynx. 12, maxilla. 13, Labium (left v. v., right d. v.).

FIGURES 14 – 17. Camelobaetidius baumgardneri sp. nov., nymph. 14, foreleg. 15, posterior margin of terga IV. 16, gill IV. 17, paraproct.

FIGURES 38 – 43. Camelobaetidius sallesi sp. nov., nymph. 38, labrum (left v. v., right d. v.). 39, left mandible. 40, right mandible. 41, hypopharynx. 42, maxilla. 43, Labium (left v. v., right d. v.).

FIGURES 44 – 47. Camelobaetidius sallesi sp. nov., nymph. 44, foreleg. 44 a, detail of tarsal claw. 45, posterior margin of terga IV. 46, gill IV. 47, paraproct.