Oxystigma

Garrison, Rosser W., 2014, Review of Oxystigma Selys with the synonymy of Oxystigma williamsoni Geijskes (Odonata: Heteragrionidae), Zootaxa 3780 (2), pp. 347-364: 349-350

publication ID

http://dx.doi.org/10.11646/zootaxa.3780.2.7

publication LSID

lsid:zoobank.org:pub:72C52670-4454-46D3-8D71-9BC8E8A98434

persistent identifier

http://treatment.plazi.org/id/7734CE70-4840-FF8D-FF57-8ED3FA1614B6

treatment provided by

Plazi

scientific name

Oxystigma
status

 

Key to males of Oxystigma 

1. Cercus in medio-dorsal view with supplementary denticulate ridge extending to basal 0.30 ( Figs. 41–42 View Figure ), transverse ridge present on medial lobe ( Figs. 41–42 View Figure ); distal portion of cercus beyond posterior margin of medial lobe short, about 0.30 of cercus ( Fig. 42 View Figure ; A> B); larger species, HW ≥24.0 mm; Sierra de Lema region, Bolívar State, Venezuela ( Fig. 58 View Figure )........ caerulans 

1 '. Cercus in medio-dorsal view with denticulate ridge extending to basal 0.50, transverse ridge absent on medial lobe ( Figs. 43– 57View FIGURES 41 – 48View FIGURES 49 – 57; vestigial in some O. petiolatum  from Rondônia State, Brazil, Fig. 56 View Figure b); distal portion of cercus beyond posterior margin of medial lobe long, about ≥ 0.45 of cercus ( Fig. 43 View Figure ; A ≈ B); smaller species, HW ≤24.0 mm; widespread in northern and central

South America ( Fig. 58 View Figure )................................................................................ 2 2 (1 '). Frons, clypeus and labrum light blue ( Figs. 2–3 View Figure ); synthorax in mature male largely black or dark brown above ( Figs. 17–18 View Figure ); cercus in dorsal view with transverse ridge prominent and not reaching posterior margin of medial lobe ( Figs. 49–51 View Figure )................................................................................................... cyanofrons 

2. Frons, clypeus and labrum mottled with black spots on a pale blue or yellow underground or largely dark to shining black, ( Figs. 6–14View FIGURES 1 – 8View FIGURES 9 – 16); synthorax in mature male black or dark brown above, with pale dorsal or humeral stripes ( Figs. 21–23 View Figure ); cercus in dorsal view with transverse ridge extending posteriorly beyond medial lobe ( Figs. 52–54 View Figure ) or to medial lobe posterior margin ( Fig. 55 View Figure ) or (populations from Ecuador and Rondônia State, Brazil) disappearing ventro-posteriorly, not forming a prominent ridge ( Figs. 56–57 View Figure )............................................................................ petiolatum