Insects on Bulrush/Reedmace

[poschiavanus]

I came across a couple of insects, or at least their traces on stems of Typha latifolia (Common Bulrush or Reedmace) today, and can't work out what they might be.

The first was a small beetle with slightly clubbed antennae gathered in large aggregations on the unopened flowers. There were several pairs mating and others wandering up and down the stem, but most were underneath the flower bracts. Size around 3-4 mm, females obviously larger than males. Elytra appeared to be hairy.



Second, on one of last year's stems I noticed many small holes quite near the top of the stem, say 75 to 100 cm off the ground. The holes were not much bigger than 1 mm, and appeared to consist of a pair, one plugged, the other open separated by about 10-12 mm. On opening up the stem I found some empty pupal cases, which looked very moth-like: impressions of antennae and legs on the case. These were around 8-10 mm long. Unfortunately I have not managed to get a decent picture of the pupal case. There did not appear to be any evidence of mining of the stem around the pupal cases, so I think the larvae crawled up the stem made bored into the stem, and made an exit window.



I can't quite square this with the information available to me about the two micro-moths which I know to feed on Typha: Limnaecia phragmitella (Cosmopterigidae) and Calamotropha paludella (Pyralidae), and the pupae are much too small for things like the Bulrush Wainscot
.

Can any one shed any light on these two creatures?

poschiavanus

[Laurence Clemons]

I think the beetles are a Telmatophilus species.

[poschiavanus]

That was wonderfully quick Laurence: much appreciated.

I see that Telmatophilus typhae is described as a palearctic 'cattail' specialist in the North American literature, and also as the commonest of the genus in Central Europe. I presume the other 4 UK species frequent similar plants/habitats, with 3 being associated with Bur-Reed in Bullock's 1992 food plant list.

Thanks again,

poschiavanus

[kielder]

Wow, what a sight! :-) great to see.

[poschiavanus]

Originally Posted by poschiavanus

Second, on one of last year's stems I noticed many small holes quite near the top of the stem, say 75 to 100 cm off the ground. The holes were not much bigger than 1 mm, and appeared to consist of a pair, one plugged, the other open separated by about 10-12 mm. On opening up the stem I found some empty pupal cases, which looked very moth-like: impressions of antennae and legs on the case. These were around 8-10 mm long. Unfortunately I have not managed to get a decent picture of the pupal case. There did not appear to be any evidence of mining of the stem around the pupal cases, so I think the larvae crawled up the stem made bored into the stem, and made an exit window.



I can't quite square this with the information available to me about the two micro-moths which I know to feed on Typha: Limnaecia phragmitella (Cosmopterigidae) and Calamotropha paludella (Pyralidae), and the pupae are much too small for things like the Bulrush Wainscot.

poschiavanus

Came across this old post of mine, and now UK Moths has much more information which suggests that these exit holes were indeed of Calamotropha paludella.