Noctuidae - Psaphidinae - Triocnemidini

Triocnemis saporis adult, male, and female genitalia

Checklist of the Species


This segment on the Triocnemidini is based on unpublished research conducted while the author was an employee of the Systematic Entomology Laboratory, USDA.


A number of disparate genera previously placed near the genera and species now included in the Oncocnemidinae, but showing a number of features that are either synapomorphies for the tribe or intermediate between the Psaphidini and Nocloini are included in this new tribe. Superficially The genera included in this tribe are superficially dissimilar. However all of them appear to share two derived characters to one extent or another. In particular the structure of the abdominal spiracles is unique. In other noctuids the spiracle is circular with an internal lever and flange plate. In most of the genera included here the distal half of the circle of the spiracle is greatly reduced or absent and usually the flange plate of the internal lever is greatly expanded. The distinctness of this character varies among genera. This condition in strongest in Poliocnemis and Oxycnemis, but the spiracle is almost normal in Triocnemis and its two related genera Triocnemidini New Genus 2 and Triocnemidini New Genus 3. Secondly the vein M2 of the hindwing is strong; also the medial vein of the hindwing is present at least at the base of the wing and the mdc cross vein of the hindwing is triangular with the apex of the triangle intercepting the medial vein or the fold representing the medial vein. This venation of the hindwing is found throughout the tribe, but to varying degrees. In the other three tribes listed above the medial vein is not as strong and the cross vein mdc is straight, not triangular. This triangular condition of mdc is strongest in Poliocnemis, Triocnemidini New Genus 1, and Oxycnemis, but Triocnemis, New Genus 2, and New Genus 3 tend toward the more conventional straight mdc. The interpretation of this venation character is difficult. The defining characters of the Triocnemidini are:

1) The antenna of both males and is females simple or weakly bipectinate.

2) The front tends to be slightly bulging but is otherwise unmodified.

3) The dorsum of the metathorax most often has two lateral and a distal median tuft although the tufts may be degenerate.

4). The prothoracic tibia has a strong claw, and the claw is always associated with a knife like ridge along the distal margin of the tibia. A secondary distal claw is always absent but sometimes a small accessory claw exists just forward of the main claw.

5). The cross vein mdc in the hindwing is usually indented into a developed medial vein, more so in Poliocnemis, New Genus 1, and Oxycnemis, less so in Triocnemis and its relatives. Vein M2 of the hindwing is generally well developed and not degenerate as in most "trifid" noctuids.

6). There is a tendency for the distal wall of the abdominal spiracles to become degenerate. This tendency is strongest in Poliocnemis, New Genus 1, and Oxycnemis, less so in Triocnemis and its relatives.

7) The valve of the male genitalia is simple with a simple clasper. The corona is absent and is replaced by dense setae except in Crimona.

8) The uncus is usually swollen and always has an apical tooth.

9). The vesica is elongate and generally has two roughly parallel rows of spines. An apical spine is always absent.

10). Basal hair pencils and accessory hair pencils are always absent except in Crimona.

11). The eighth abdominal tergum of the male is always enlarged, sclerotized, and with its distal edge weakly bilobed.

12). The female ovipositor lobes are usually normal but in a few genera there are various forms of modification.

13) The bursa is usually ovate. The appendix bursae is always missing and the ductus seminalis arises from a distal projection of the corpus bursae.

14) When signa are present they are in the form of an elongate ridge shaped like a row of bricks.

15) The external tympanic region consists of a large hood followed in the middle of the intersegmental membrane by an ovate or rectangular large bulla.