Weevil - Mesites subcylindricus

Moved

Moved from Mesites.

… Aaron Hunt, 22 April, 2016 - 11:09am

Mesites sp.

Specimen a photo-voucher. Thanks Aaron.

I am not confident placing a species name on these, despite having a series of 10 individuals of both sexes that you sent me. Body length ranges between 4 to 6 mm.

These species, to my knowledge, have not been reviewed since their originial descriptions, and the characters separating them seem to be subjective and variable. Color is said to be red in rufipennis but these having a variable shade from almost black to dark reddish. Size of rufipennis is given as 5 to 5.3 mm, and these clearly exceed that range. However the other species, subcylindricus, is reported at 6.5 mm with no range given. The degree of punctures on the intervals leans toward rufipennis in my opinion, but the descriptions seem difficult to interpret, and I can't see a difference between the type images on MCZ.

Based on key characters I would say it is closer to M. rufipennis, but simply eyeballing the type images on MCZ I would say M. subcylindricus.

… Brad Barnd, 15 December, 2015 - 1:08am

Mesites

A quick update: I finally found Derek Sikes's full list of Block Island beetles here. He included Mesites subcylindricus in his checklist, with the first New England record sometime between 1996 and 2001. Just to be clear, I'm not in any way questioning your judgement. I just wanted to add this tidbit. I wonder how many specimens he collected and if maybe a more limited number made the ID seem clearer just by chance, which makes me especially glad I collected so many. As an aside, I just finished comparing the lists and found that 95 of the species I found we first records for Block Island and only 74 had previously been recorded here.

… Aaron Hunt, 18 April, 2016 - 2:14am

thanks Aaron

I think its safe to put these under M. subcylindricus, seeing as specimens have been collected there before and were identified by R. Anderson (1).

I'm sure the number of new records for Block Island will steadily increase because of your efforts. Awesome job!

… Brad Barnd, 20 April, 2016 - 7:28pm

Sexually dimorphic?

I'm back at the beach where I found the beetle and found a huge log nearby infested with them. I collected several dozen and noticed that some have reddish elytra while others, like the first specimen, are all black. They vary in size somewhat but I'm not sure whether the two forms tend to be different sizes -- I'll know more when I look at them tonight. Could I have found two species or just makes and females?

… Aaron Hunt, 8 July, 2015 - 2:27pm

Yes

Females have very narrow rostrums with basal antennal insertions. Males have a more robust rostrum with antennal insertion at basal 1/3. Both sexes vary widely in size.

… Brad Barnd, 19 February, 2022 - 10:01pm

Moved

Moved from Beetles.

… v belov, 8 July, 2015 - 8:29am

looks very intriguing... distinctive... and exotic

from what i can make out of this shot, it's more likely a molytine than a cossonine, but i haven't seen anything like it
the narrow snout with bulgy eyes remind me of some 'primitive' weevils, members of certain minor families, but those tend to have non-geniculate antennae

… v belov, 7 July, 2015 - 10:54pm

Genus Mesites

It's a species of the genus Mesites (Cossoninae). I'll see if I can determine which species it is.

… Robert Anderson, 8 July, 2015 - 8:02am

Great! If you can't let me know what could help.

I still have the specimen and can take more pictures if needed.

… Aaron Hunt, 8 July, 2015 - 8:10am

I'll take several shots of legs, antennae, etc.

Hopefully that'll give you a better idea of what it is.

… Aaron Hunt, 7 July, 2015 - 11:18pm