Erpetogomphus oxybelis, Ortega-Salas, 2018

Ortega-Salas, Héctor, 2018, Erpetogomphus oxybelis sp. nov. from Veracruz, Mexico (Odonata: Gomphidae), Zootaxa 4378 (4), pp. 589-594 : 589-593

publication ID	https://doi.org/ 10.11646/zootaxa.4378.4.10
publication LSID	lsid:zoobank.org:pub:A62159A9-375E-42E1-9037-A9585677359A
DOI	https://doi.org/10.5281/zenodo.5946767
persistent identifier	https://treatment.plazi.org/id/03CC87E1-D138-FF80-FF14-F8FEFAE9FA68
treatment provided by	Plazi
scientific name	Erpetogomphus oxybelis
status	sp. nov.

Treatment

Erpetogomphus oxybelis View in CoL sp. nov.

( Figs. 1 – 4 View FIGURE 1 View FIGURE 2 View FIGURE 3 )

Holotype. ♂ ([ PSUC] PSUC _FEM 70665), México: Veracruz state, Tres Valles municipality; Río Hondo , at bridge on Los Naranjos circuit, 10.6 km NE from Mex. 145 Sayula de Alemán-Tierra Blanca Hwy. (18.387 N, - 96.174 W, 20 m a.s.l.) 18 August 1957, G.H. & A. Beatty leg. GoogleMaps

Etymology. With the intention of following the historical nomenclature of the genus, this species is named oxybelis as in the colubrid genus.

Description of holotype. Head. Pale areas dull green, dark markings light brown. Labrum pale with dark margin, anteclypeus pale, darkening medially, postclypeus dark with lateral pale spots, antefrons pale with dark line along margin, vertex, occiput, antennae all brown, a small tubercle behind each ocellus; occiput mostly planar, slightly tumid medially, crest slightly concave covered with brown setae ( Figs. 1 View FIGURE 1 ; 3b, c).

Thorax. Prothorax brown except for: anterior lobe with a yellow stripe covering half of its width along anterior margin and narrowing toward lateral 0.2 ( Fig. 1 View FIGURE 1 ). Pterothorax with pale areas yellow green. Middorsal stripe widening basally to collar, its upper end covering antealar sinus and extending posteriorly and connecting with both broad, well defined antehumeral and humeral stripes; second lateral stripe sinuate and ill-defined specially on its upper half; third lateral stripe present; posterior margin of metepimeron covered with thin white hairs; coxa and trochanters pale gray with slight wash of brown on joints; femur brown darkening apically; tibiae, tarsi and claws black ( Figs. 1 View FIGURE 1 ; 3a).

Wings. Hyaline, venation black, pterostigma dark brown ( Fig. 1 View FIGURE 1 ); in FW fifth (left) and sixth (right) antenodal thickened, in HW fifth antenodal thickened; Ax: FW 14/15, HW 10/11; Px: FW 12/12, HW 11/11; crossveins under pterostigma: FW 5/4, HW 4/5; anal triangular cells: 4/4; HW 24.3 mm.

Abdomen. S1 yellow with laterodorsal brown spots covering 0.5 apical of the segment length, these spots with tufts of brown hairs. S2 brown except for a yellow middorsal stripe widening at midlength, auricle yellow. S3 – 4 with a narrow middorsal yellow stripe on the basal 0.8. S5 like S3 – 4 but line is considerably narrower and diffused. S6 with a basal yellow ring on 0.25, extending as a dorsal stripe to 0.5 of the segment length. S7 like S6 but with a ring of 0.5 and stripe extending to 0.7. S8 brown with latero apical pale spots. S9 – 10 reddish brown with black transverse carina, posterior medial margin of S9 pointed; abdomen length 28 mm ( Fig. 1 View FIGURE 1 ).

Accessory genitalia. Anterior hamule light to dark brown, branched at distal 0.25, superior branch larger than inferior, superior branch with inner margin black; posterior hamule roughly triangular, apical tooth acute and straight ( Fig. 2g, h View FIGURE 2 ); fourth segment of vesica spermalis with cornuae bilobed (right lobe of holotype broken), posterior lobe triangular and twice as long as proximal lobe, proximal lobe round and directed laterally; prepuce well developed, lateral lobe a small rounded tooth ( Fig. 2e, f View FIGURE 2 ).

Caudal appendages. Cerci reddish-brown becoming dark brown posteriorly, arcuate with a prominent laterally compressed dorsal tubercle on distal 0.75, extreme base with a ventral blunt tooth (mostly hidden by posterior margin of S10), a ventral convex carina on distal 0.25 of cercus armed with an apical black tooth preceded by a small notch; epiproct light brown with a dorsal tubercle at 0.5 and its posterior 0.3 curved upward at 90° angle, tips triangular when viewed posteriorly, with black points directed laterally, its dorsal margin transverse to the medial axis of the abdomen ( Figs. 1–2a, b, c, d View FIGURE 1 View FIGURE 2 ).

Diagnosis. Males of E. oxybelis are easily separated from most species of Erpetogomphus by the presence of a laterally compressed dorsal tubercle on the 0.25 distal of the cercus ( Fig. 2a, b d View FIGURE 2 ). It can be distinguished from its closest allies of the ophibolus group: Erpetogomphus constrictor Ris, 1917, E. sabaleticus Williamson, 1918, E. tristani Calvert, 1912 and E. ophibolus Calvert, 1905 by the shape of the vesica spermalis. In E. oxybelis this structure has a well-developed bilobed cornuae ( Fig. 2e, f View FIGURE 2 ), while in the other four species the cornuae is lost (Garrison 1994: Figs. 70–73). The shape of the epiproct separates this species from E. constrictor, E. sabaleticus and E. tristani; in these species this structure has the tips recurved so as to lie parallel to the base (Garrison 1994: Figs. 92–94), while in E. oxybelis is gently curved upwards at a 90° angle ( Fig. 2a View FIGURE 2 ). In E. oxybelis the cerci have a small notch proximal to the apical tooth ( Fig. 2a View FIGURE 2 ), which is not present in E. constrictor and E. ophibolus (Garrison 1994: Figs. 92, 95). The shape of the epiproct further separate E. oxybelis from E. ophibolus; in the first this structure is ca. 0.4 the length of the cerci ( Fig. 2a, b, c View FIGURE 2 ), while in the latter is ca. 0.9 (Garrison 1994: fig. 95).

Habitat and ecology. The only data available on this species is that from G. H. & A. Beatty’s field notes: Large muddy creek, sand, mud and gravel bottom, 10 – 15’ ft. wide; 3 – 4’ deep, high dirt banks. Evidence of water rising 10 – 12 ’ during rainy season. Other gomphid species collected at the same site: Progomphus clendoni Calvert, 1905, Phyllocycla volsella (Calvert, 1905), Erpetogomphus bothrops Garrison, 1994, E. ophibolus, Agriogomphus tumens (Calvert, 1905), and Phyllogomphoides sp.

Distribution. Known only from the type locality ( Fig. 4).

Notes. In an unpublished report from 1962, G.H. and A.F. Beatty made reference to this individual as Erpetogomphus sp. nov. 3, later they gave it the ms. name “zookie” after Lester Zook, a rural missionary. Among the material collected in the Beatty’s expeditions there was a female individual labeled as Erpetogomphus “zooki” which after closer inspection turns out to be a misidentified female of Erpetogomphus eutainia Calvert, 1905 .