Dysagrionites, Archibald & Cannings

Archibald, Bruce, Cannings, Robert A., Erickson, Robert J., Bybee, Seth M. & Mathewes, Rolf W., 2021, The Cephalozygoptera, a new, extinct suborder of Odonata with new taxa from the early Eocene Okanagan Highlands, western North America, Zootaxa 4934 (1), pp. 1-133 : 106

publication ID

https://doi.org/10.11646/zootaxa.4934.1.1

publication LSID

lsid:zoobank.org:pub:79895443-4597-42A5-AF8A-023EACB20E10

DOI

https://doi.org/10.5281/zenodo.4672721

persistent identifier

https://treatment.plazi.org/id/03B487C2-007B-FFFE-FF5B-FD8FFCAF17F1

treatment provided by

Plazi

scientific name

Dysagrionites
status

 

Dysagrionites sp. A

Fig. 63B View FIGURE 63 .

Material. SR 96-12-03 ( Fig. 63B View FIGURE 63 ), collected at Republic B 4131 by Les Larson, 15.x.1996, housed in the Stonerose Interpretive Center collections .

Description of SR 96-12-03. The mid-portion of wing apical to about origin of RP2 to shortly distal to origin of IR1 anteriorly diagonally to shortly proximal to terminus of RP3-4. Width estimated 6.5 mm. hyaline throughout. Few preserved crossveins in proximal postnodal, postsubnodal spaces aligned. RP1–IR1 space does not become two cells wide in preserved portion. IR1: origin three cells distal to that of RP2; RP2–IR2 space becomes two cells wide ten cells distal to origin. RP2 linear, rather straight through preserved portion. IR2, RP3-4 origins not preserved, rather linear, slightly zigzagged in places, rather straight through preserved portion. MA increasingly zigzagged through preserved portion. MP linear, slightly curved in portion preserved to near terminus. CuA zigzagged throughout preserved portion. CuA–A space mostly preserved, from just proximal to level of origin of RP2 almost to distal end; two cells wide throughout with one column of three.

Range and age. Okanagan Highlands, Thumb Tuff Member of the Klondike Mountain Formation at Republic, Washington, USA, exposure B4131; late Ypresian.

Discussion. This middle portion of a wing most resembles Dysagrionites delinei in that it is narrow, hyaline, three cells from origin of RP3-4 to origin of IR1 [ D. delinei 3–4], CuA linear to mid-wing, then begins to zigzag (distal portion not known). It differs, however in the CuA–A space being two cells wide (one column three), whereas in D. delinei it is three cells wide. It differs from Furagrion and hyaline species of Okanagrion by CuA zigzagged in distal portion to the margin, whereas in Furagrion it is lightly zigzagged in mid-wing, returning to linear in the distal portion to the margin, and in Okanagrion it is linear throughout. It differs further from hyaline Okanagrion species by the narrow CuA space [four or more cells wide]. Although it is distinct in these ways, we prefer to wait to name this species until a more complete specimen is found that would allow a more through definition, and given the chance of sexual dimporphism in wing colouration.