Oreiallagma acutum Ris 1918, comb. nov.
Creators: name: Ellenrieder, Natalia Von
name: Garrison, Rosser W.
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Odonata
Coenagrionidae
Oreiallagma
Oreiallagma acutum

description: Oreiallagma acutum (Ris 1918) comb. nov.
Figures 27; 51; 85; 90; 104
Acanthagrion acutum Ris 1918: 120 –122, figs. 61–62 [mislabeled as 59] (description of male, illustration of S10 and wings).
Cyanallagma acutum Kennedy 1920: 87 (inclusion in Cyanallagma).
Davies & Tobin 1984: 66 (synonymic list).
De Marmels 1989: 246–247, figs. 1–7 (notes on male and illustrations of head, posterior lobe of prothorax, S7–10, genital ligula, and S10).
Garrison 1991: 11 (synonymic list).
Bridges 1994: VII.3 (synonymic list).
Steinmann 1997: 247 (synonymic list as Cyanallagma acuta). De Marmels 1997: 138, fig. 82 (key to northern Cyanallagma species, map, comparison with C. thelkterion). Tsuda 2000: 31 (synonymic list).
Types: Ris (1918) described this species based on nine males (three from Río Zongo, six from Coroico) but did not designate a holotype. We examined a male syntype labeled "Río Zongo, 800 m. / BOLIVIA. [La Paz Dept.] 1913 (2), A.H. Fassl", which also has a red label "Lecto-[in ink by an unknown hand]/Para-/typoid [printed]" affixed to the envelope. De Marmels (1989) stated that he examined two paralectotypes from Coroico. In order to clarify application of the name, we designate the specimen we examined as lectotype (Senckenberg Register No. 10196) that served as basis for our Figures 27; 51; 85; 90. In FNS.
Characterization. Medial lobe of posterior lobe of prothorax slightly constricted at base, subquadrate, with shallow medial concavity on posterior margin (Fig. 27; as in O. oreas and O. quadricolor). Distal segment of genital ligula (Fig. 51) approximately as wide at apex as at base with a pair of latero-apical lobes recurved and directed basally, no accessory latero-medial lobes (unique), and two ental membranous transverse folds (as in O. quadricolor and O. thelkterion). Dorsal process of male cercus approximately as long as ventral process (Figs. 85; 90; unique). Dorsum of S1–7 black, of S8–9 blue, sides of S3–7 reddish-orange, of S8 with a black stripe along anterior 2/3, S9 entirely blue and S10 entirely black. Female unknown.
Diagnosis. Species unique by cercus morphology: the long, digit-like dorsal process (Fig. 85) is shared only with O. thelkterion (Fig. 86) but is more robust and as long as or longer than ventral process (Figs. 85; 90); in O. thelkterion, dorsal process is more acuminate and shorter than ventral process (Fig. 86). In O. prothoracicum (Figs. 87; 92) and O. quadricolor (Figs. 88 a; 93), dorsal process is small and acute, and in O. oreas it is represented by a blunt setose tubercle (Figs. 89; 94).
Biology. Unknown; see remarks under generic account.
Distribution. Bolivia (La Paz Department), from 800 to 1400 m above sea level (Fig. 104).
description: Published as part of Ellenrieder, Natalia Von & Garrison, Rosser W., 2008, Oreiallagma gen. nov. with a redefinition of Cyanallagma Kennedy 1920 and Mesamphiagrion Kennedy 1920, and the description of M. dunklei sp. nov. and M. ecuatoriale sp. nov. from Ecuador (Odonata: Coenagrionidae), pp. 1-51 in Zootaxa 1805 on pages 44-45, DOI: 10.5281/zenodo.182666