Bug FAQEctophasia crassipennis
Ectophasia crassipennis · Order: Diptera · Family: Tachinidae
Adult Ectophasia crassipennis are 5 to 9 mm long and show variable blackish to orange-brown colors with reddish eyes. They live in southern and warm central Europe and parts of Asia such as Russia, Japan and China, where they are seen from early August to late September. Adults feed on flower nectar, especially from Apiaceae and Asteraceae, while their larvae are parasites of various true bugs.
Source: Wikipedia
How to recognize it
The fly has a broad, flattened abdomen with a folded sternite 7, large wings with brownish or greyish spots, and an open cell R5 at the wing edge. Its large compound eyes are reddish.
Source: Wikipedia
Size
Adults measure about 5 to 9 mm (0.20 to 0.35 in) in length.
Source: Wikipedia
Where it lives
It inhabits diverse habitats across southern Europe and warmer central Europe. It is also found in Asian regions including Russia, Japan, and China.
Source: Wikipedia
What it eats
Adults mainly sip nectar from flowers, especially those of the Apiaceae and Asteraceae families. Larvae are parasitic on hemipteran bugs like Pentatomidae, Acanthosomatidae, Coreidae and Lygaeidae.
Source: Wikipedia
Life cycle
The larval stage parasitizes various true bugs (Hemiptera).
Source: Wikipedia
When you see it
Adults are most commonly seen from early August through late September.
Source: Wikipedia
Where it comes from
Its native range includes southern Europe, warm central Europe, and parts of Asia such as Russia, Japan, and China.
Source: Wikipedia
Lookalikes
It can be hard to tell apart from the similar species Ectophasia oblonga.
Source: Wikipedia
Where it is found in the US
Recorded in 1 of 51 states and DC. Most records: California.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
More photos
Questions people ask
When can I see these flies?
They are most common from early August to late September.
Source: Wikipedia
What do the larvae feed on?
The larvae parasitize several families of true bugs, such as stink bugs and leaf-footed bugs.
Source: Wikipedia
Where does this species live?
It occurs in southern and warm central Europe and in Asian countries like Russia, Japan, and China.
Source: Wikipedia
Same family (Tachinidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Ectophasia_crassipennis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.