Can anyone help me identify this tiny larva I found in my cat's water dish and tell me how it got there?enter image description here

  • 4
    $\begingroup$ It is not likely that identity can be obtained from a larval stage photo only, so you do need to provide more information. Can you provide its size and where you are located? Possibly an insect specialist might have an idea. It is not possible to tell you how it got there. $\endgroup$
    – user22542
    Jul 28 '18 at 19:05
  • 2
    $\begingroup$ This is the larva of a moth fly (family Psychodidae: I don't see any legs, there is a well-developed head capsule, and the body segments each have two or three dorsal plates); going further than that requires knowing where you are, and whether or not the Psychodid fauna of that area is well-known as larvae (in practice, this means "forget going deeper" if not located in western Europe). Larvae of the subfamily Psychodinae (which this is) are aquatic or semiaquatic, which means that a week or so ago an adult laid one or more eggs where you eventually found the larva. $\endgroup$ Jul 29 '18 at 18:56

This appears to be the larva of a drain fly (aka moth fly; family Psychodidae).

enter image description here

Top left is larva; Source: YourWildlife.org; Credit: Matt Bertone

You can use a dichotimous key to help you ID to family. For example, from Bouchard et al. (2004)+:

  • Body cyclindrical; non-leathery integument...
  • Head capsule fully visible and completely separated from thorax
  • Prolegs absent
  • Thoracic segments not fused or swollen
  • Abdomen non ending in long respiratory tube
  • Body segments with 2-3 secondary divisions (annuli); body grey or brown

You can use Arthur Frost's comment to help ID to lower taxonomic levels.

How it got there:

From Orkin:

These pests are particularly likely to be found in bathrooms and kitchens, typically getting into homes through:

  • Basements
  • Drains
  • Windows

+ Bouchard, R.W., Ferrington, L.C. and Karius, M.L., 2004. Guide to aquatic invertebrates of the Upper Midwest. (Chapoter 13: "Diptera")


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