Lamelligomphus

May 31 and June 1 I visited Xuan Son and Yen Bai (near Nam Bung along the QL32). I was very happy to run into several Lamelligomphus. Last year these gave me quite a bit of a headache and they still do to some extent, but at least Haruki Karube has solved some of the puzzle. There are at least 4 species in Vietnam. L. camelus, a large species with humps on S8, the others without humps. L. formosanus I already found last year and has a clear thumb to the anterior hamulus. Then there is a small southern species, L. castor, published by Karube. And there is the species I found last year October, possibly L. hainanensis, but it may be too big for that species and the antehumeral stripe and collar are confluent. Presently the specimen is with Karube, so I cannot measure it, but it is for the time being better considered as Lamelligomphus sp.

Now on May 31 and June 1 I saw several males and one female L. camelus in Xuan Son and on June 1 also found two male Lamelligomphus near Nam Bung. This last species fits in measurements (HW 36mm, ABD 41mm) and penile organ, appendages, hamulus very well with L. hainanensis, but it has all black labrum, where it is supposed to have yellow spots on it. In view of the structural match with L. hainanensis, I consider this for the time being to be that species. Anyway I must say, I just love these weirdos, hovering low above the streams, with their massive appendages.

Lamelligomphus camelus, male

L. camelus, male, facial pattern

Lamelligomphus camelus, female. note humeral line and spot and yellow on flanks, quite more extensive patterning than male

L. camelus, female facial pattern

The humps on S8 characteristic of male L. camelus

Likewise, very characteristic appendages, with dorsal tooth at one third of the superior appendages

Lamelligomphus hainanensis, male

But note facial pattern with continuous stripe over frons and all black labrum

Relatively simple appendages, with small teeth on ventral side of bend of superior appendages, but simple apices to inferiors