Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada

cauda, caudal

Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
No Taxon (Glossary)
No Taxon (C)
No Taxon cauda, caudal
Explanation of Names
Latin cauda tail, caudal from New Latin adjectival form caudalis.
Identification
cauda noun - in aphid anatomy, a tail-like protrusion above the rectal aperture (Wikipedia--Aphid). Also similar structures in other groups, such as both larval and adult mayflies (Ephemeroptera), where often called caudal filaments.
caudal adjective - pertaining to the tail or posterior or hind part of a body (Wiktionary)
caudally adverb - towards the posterior end.

Photographs showing the cauda:
Internet References
Wikipedia--Aphid
Wiktionary--caudal