We collected a nepticuloid moth from sand dunes in southern California that has a 2mm wingspan.

Wow

Did you publish anything, is it a described species?

Thanks for the answer...

We couldn't find anyone willing to try to identify it.

This was not my intention but... doy ou have many? Say, to take the dry weight of a couple of males that could also be measured.

There are not many experts in the group, those that have the expertise normally do not have the time! (this is at least my experience)

Chhers

The smallest of all Lepidopterans are the Nepticulidae and Lyonetiidae with an average wing span of only 2 mm. The caterpillars live in mines, under leaves, and a few are gall makers, but even more interesting are the parasitoids of those moths in the family Eulophidae with a size of  only 1 mm in average. See for instance the coffee leaf miner Leucoptera coffeella

https://www.researchgate.net/publication/263280284_The_coffee_leaf_miner_Leucoptera_coffeellum_Lepidoptera_Lyonetiidae_A_potential_pest_by_effects_of_climatic_change

https://www.researchgate.net/publication/305777321_Diagnostic_of_Leucoptera_coffeella_Lepidoptera_Lyonetiidae_and_its_parasitoids_in_the_department_of_Antioquia_Colombia

Technical Report The coffee leaf miner Leucoptera coffeellum (Lepidoptera: Ly...

Article Diagnostic of Leucoptera coffeella (Lepidoptera: Lyonetiidae...

 Fantastic, lots of thanks

Hi, @ Lynn Kimsey,

have you asked Erik van Nieukerken to look ath the nepticuloid?

Cheers.

Yes, Lynn... he is too busy! At least he was by the last time I tried. But I don't give up,  I have a few specimens waiting for an expert!

Cheers

Enrique

Hi all, the smallest are tropical species, usually unnamed ones. I have seen very small Stigmella's and Phyllocnistis from the tropics. I should go back to the collection to take actual measurements, but I guess a wingspan of ca 2.5 to 3 mm is possible. Luis, I don't agree to the idea that the 'average wingspan of nepticulids or lyonetids is 2mm', but that is a common forewing length and many are smaller indeed. Also some Coptodisca species (Heliozelidae) in North America are very small.

Some actual figures:

Stigmella diniensis, France: forewing length 1.3-1.6 mm

Stigmella ebbenielseni, Guam: fw length 1.5-1.9 mm

Stigmella betulicola, Europe: wingspan 3.4-4.6

Enteucha acetosae, Europe: wingspan 3.0-4.0 mm

Lynn: I am interested in your Californian specimen.

Erik

I'll see if I can find it. It came in a Malaise trap sample and may still be in alcohol. We also have a tiny one from Congo that I'll look for.

Lynn

great, contact me at e-mail! 

Fantastic, thanks for all comments!

In my collection Enteucha acetosae (Nepticulidae) is the smallest species. I bred about  fifty specimens of this species this year. The wingspan (including fringes) of the largest specimen is 4.1 mm, the smallest only 2.65 mm.

So this was really useful to get a preliminary estimate. There is a technical tie between S. diniensis and E. acetosae. I did not find a representation of the first one (described as 'Mit einer Expansion 3-3.10 mm zu den kleinsten Nepticuliden gehörig': Klimensch, 1975) while a photo of the second is shown in Lepiforum: http://lepiforum.de/lepiwiki.pl?Fotouebersicht_Nepticulini_Gesamt_1_Gespannt

 According to Thomas, the tiniest E. acetosae (probably males) would be even smaller than S. diniensis. The difference with other Nepticulids would not be so striking to the naked eye (see my composition below) but it would very probably represent a 50% decrease in body weight compared to 'my' specimen.

Thanks to all!

http://lepiforum.de/lepiwiki.pl?Fotouebersicht_Nepticulini_Gesamt_1_Gespannt

Enrique,

a other small Nepticulidae (Stigmella maya, wingspan 2.8-3.3 mm)  is described in this  paper:

Stonis, J.R., Remeikis, A., Diskuš, A. & Noreika, R. 2013. New Nepticulidae species (Insecta: Lepidoptera) from Yucatán Peninsula (SE Mexico). – Zootaxa 3609 (2): 223-230.

Yours sincerely

Thomas

Thanks, Thomas!

Enrique, S. diniensis is a rare species, but on average it is much smaller than E acetosae. Once more specimens are reared smaller specimens will surely turn up. The reason it is smaller, is because the diniensis caterpillar only has the very small leaf of Fumana, whereas acetosae can use a much larger Rumex leaf.

For what it is worth, our sole specimen (a male paratype) of S. diniensis measures almost exactly 3.0 mm (including fringes), whereas S. maya was cited as FW length 1.4–1.5 mm; wingspan 3.04–3.27 mm (n=3 males) and FW length 1.3–1.4 mm; wingspan 2.8–3.0 mm (n=3 females), so that S. maya might still be the record holder among described species (but not now individuals), perhaps until measurements for a range of S. diniensis become available. A claim have been made for a smaller unidentified nepticulid specimen from the Congo at Bohart Museum by Steve Heydon with a FW length measuring on screen around 0.85 m and an estimated wingspan between 2-2.5 mm wingspan but that is from a malaise trapped specimen with fringes lost so may not be strictly comparable: http://entomology.ucdavis.edu/News/Smallest_Moth_in_the_World/.

Dear Enrique,

It seems, you always raise interesting questions :-).

Stigmella maya Remeikis & Stonis, 2013 (Nepticulidae) is one among the smallest moth in the world. Minimal wingspan length: 2.64 mm (male), 2.57 mm (female) (J. R. Stonis, unpublished/pers. comm). An illustration is attached.

Do you know which species is the most sexy in the family Nepticulidae? (It's not a joke. But still funny; more info: [email protected])

Regards, Jonas (Rimantas)

Best thanks, Jonas... I shall look for your Zootaxa paper.

Could it be that 'smallness' is sexy among the Nepticulids? Your suggestion raises the basis for an exciting debate!

Cheers

Dear Enrique,

I see, you got plenty good ideas!

"Sexy" it's a very subjective category, particularly in the world of moths :-). Nevertheless British or Americans say: "sexy car", "sexy building", even "sexy cat". I think we found "the sexiest" nepticulid female ever:-). Perhaps we all feel some excitement when a new species is discovered (but perhaphs not necessary sexual...).   

However, this time, it is not about new species and certainly not about the minute size of some Lepidoptera. It's about peculiar reproductive organs of these tiny creatures. See attached.

Cheers