Camelobaetidius shepardi Randolph & McCafferty, 2001

Sibaja-Araya, Fabián & Esquivel, Carlos, 2020, Redescription of four species of Camelobaetidius Demoulin, 1966 (Ephemeroptera: Baetidae) from Central and North America, Zootaxa 4758 (2), pp. 257-274 : 267-272

Camelobaetidius shepardi Randolph & McCafferty, 2001

( Figures 8–11 )

Camelobaetidius shepardi Randolph & McCafferty, 2001: 17 ; McCafferty et al. 2004: 207; Meyer et al. 2008: 136; McCafferty, 2011b: 324.

Diagnosis. Mature nymph. The following combination of characters can be used to diagnose C. shepardi from remaining species in the region: 1) labrum with anterior margin with about 17 small, double frayed setae; 8–9 setae on anterodorsal arc, about 15 anterolateral setae; intermediate setae present but often inconspicuous; several micropores near anterodorsal arc; three short setae near lateral margin; one minute seta on anterior margin on both sides of cleft ( Fig. 9a ); 2) segment II of labial palp with round (female) or truncate (male) distomedial projection ( Figs. 10a, 10b ); 3) osmobranchia absent from coxal bases; 4) each tarsal claw with 21–29 denticles ( Fig. 11a ); 5) posterior margin of abdominal tergum IV with triangular spines subequal in length ( Fig. 11b ); 6) paraproct with 2–3 spines ( Fig. 11c ).

Description. Mature nymph body length: 4.0– 6.2 mm; caudal filaments length 1.5–2.3 mm.

Body coloration: dark and light olive and white pattern; pronotum and metanotum homogeneous dark olive; mesonotum with elongate, dark olive spots; abdomen with tergum I and anterior half of tergum II white, posterior half of tergum II and terga III–VII dark and light olive, tergum VIII and anterior half of tergum IX white; small, light olive spots on tergum VIII; posterior half of tergum IX and tergum X dark olive ( Figs. 8A, 8B, 8C )

Head: Labrum ( Fig. 9a ): Broader than long; round, symmetrically emarginateat apex, arc of anterodorsal setae with 8–9 setae, two inner setae frayed, rest simple; intermediate seta present but sometimes inconspicuous; several micropores below anterodorsal arc; several small setae near posterior margin; anterior margin with about 17 small, double, frayed setae; lateral margin with 6 simple setae and 9 apically frayed, long setae; ventral surface with dense arc of short, fine setae near anterior margin; three short setae near lateral margin; one minute seta on anterior margin on both sides of cleft. Left mandible ( Fig. 9b ): incisors worn; prostheca well-developed; two minute setae between prostheca and mola; several small, simple setae on basal region. Right mandible ( Fig. 9c ): incisors worn; prostheca well-developed; two short, simple setae between prostheca and mola; molar disk well-developed; several small, simple setae on basal region. Hypopharynx ( Fig. 9d ): lingua about 2x wider, but shorter than, superlinguae, apically pointed, hairy on dorsal and ventral surfaces in upper half; superlinguae with upper half hairy on dorsal and ventral surfaces and with serrate area at middle of lateral margin. Maxillae ( Fig. 9e ): robust, with several micropores on basal region; galea with four apical denticles and two apical rows of setae, some setae of one of these rows large and thick while others thin, and setae of other row shorter and curved; four setae on lacinia; palp not surpassing apical denticles, segment I short, segment II thick with few marginal fine setae and several micropores, segment III elongate with several marginal fine setae, longer than segment II. Labium ( Figs. 10a, 10b ): robust; glossae shorter than paraglossae, bothe dorsally with numerous elongate and curved setae; ventrally with several elongate and curved setae; palpi with segment I thick, as long as segments II + III, dorsal surface with numerous micropores; segment II with truncate (male, Fig. 9a ) or round (female, Fig. 9b ) distomedial projection, dorsal surface with numerous micropores, and 3–6 short, simple setae in upper half; ventral surface with numerous fine setae; segment III short and rounded, more developed than distomedial projection, with numerous short, robust spines on ventral surface, dorsal surface with row of short and robust setae on apex.

Thorax: Hind wing pads present; osmobranchia absent from coxal bases; each claw with 21–29 denticles ( Fig. 11a ).

Abdomen: Posterior margin of tergum IV with small, triangular spines subequal in length and simple, fine setae surpassing length of longest spines ( Fig. 11b ); paraproct with 2–3 sclerotized spines, and simple, fine setae on dorsal surface, posterior margin with small triangular spines ( Fig. 11c ).

Distribution: Mexico, Guatemala and Nicaragua ( Randolph & McCafferty, 2001; McCafferty et al., 2004; Meyer et al., 2008).

Material examined: Paratypes, three mature nymphs (two males and one female): México, Queretaro, Neblinas, Río Ayutla , 13.VII.2000, W. D. Shepard [ PERC] [There is no Ayutla River on Neblinas and on the list of the examined material Randolph & McCafferty (2001) wrote exactly the same data listed above, except for Río Verdito instead of Río Ayutla. Our conclusion, therefore, is that the name of the river on the paratypes label is not correct] .

Figures

FIGURE 8. Camelobaetidius shepardi Randolph & McCafferty 2001, nymphs. Body coloration, A–B) males, C) female.

FIGURE 9. Camelobaetidius shepardi Randolph & McCafferty 2001, nymph. a) labrum (left d. v., right v. v.), b) left mandible, c) right mandible, d) hypopharynx (left d. v., right v. v.), e) maxilla.

FIGURE 10. Camelobaetidius shepardi Randolph & McCafferty 2001, nymph. labium (left d. v., right v. v.), a) female, b) male.

FIGURE 11. Camelobaetidius shepardi Randolph & McCafferty 2001, nymph. a) claws, b) IV tergum spines, c) paraproct.