# Mud dauber

*Sceliphron caementarium and related genera*

**Identification confidence:** Identifiable with care

## How to recognise it

- The waist is extremely long and thread-like, far more elongated than any other common wasp — this alone identifies the group.
- Body is slender, 12 to 25 mm, usually glossy black, sometimes with yellow markings or a metallic blue sheen.
- The nest is a hardened mud structure — either a smooth lump or a set of parallel tubes resembling organ pipes — plastered to a sheltered vertical surface.

## What it leaves behind

- Mud tubes or lumps on walls, ceilings, under eaves, in garages and sheds, and in disused equipment.
- Solitary wasps flying slowly and repeatedly to the same spot carrying mud.

## Why an infestation persists

Solitary and non-defensive; they do not guard the nest and sting only if handled directly. They provision nests with spiders, including widows, so they are genuinely beneficial. Old nests are frequently reused by other insects.


## Where it occurs

Throughout the United States.

## What prevents it

- Scrape old mud nests off surfaces once activity has ended, then clean the area.
- Screen open sheds and outbuildings if nesting is unwanted.

## Commonly confused with

- **Paper wasp** (*Polistes spp.*) — Long, slender body with a very narrow waist, 16 to 25 mm, usually brown with yellow or reddish markings.

**Verdict:** prevention-first. Non-aggressive, beneficial, and nests are removed mechanically once inactive.

Source: https://againstpest.shop/identify/stinging-insects/mud-dauber/