COMPARATIVE ANATOMY OF THE INSECT TRACHEAL SYSTEM PART 1: INTRODUCTION, APTERYGOTES, PALEOPTERA, POLYNEOPTERA Author Herhold, Hollister W Author Davis, Steven R Author Degrey, Samuel P Author Grimaldi, David A text Bulletin of the American Museum of Natural History 2023 2023-03-31 459 1 1 184 http://dx.doi.org/10.5531/sd.sp.55 journal article 10.5531/sd.sp.55 eb1717dc-9526-481c-a859-7ca8fd036425 0003-0090 7730159 Neocloeon triangulifer subimago “Triangle small minnow mayfly” Figures 24 (lateral), 25 (dorsal, ventral) Plates 14 (lateral), 15 (dorsal, ventral) DESCRIPTION: BODY : Several alimentary canal air spaces present, fusing into single one in adult. HEAD : H-DCT and H-VCT similar in size, extend into head capsule from prothorax. THORAX: T 1-DVi branches from H-VCT on left side, H-DCT on right. ABDOMEN: A 2..7-Gi gill attachments visible laterally on A n - DLT , midway between spiracles; A 1-Gi on posteroventral extension from A 1- S , reduced in adult (no other vestiges of gill attachment sites present in adults). Several dorsal visceral tracheae extend anteriorly beyond segment boundaries; ventral Vi (retained) within segment.