Is it a butterfly or … ?

On every butterfly and moth,
a coiled proboscis for a mouth,
which when extended and unrolled
can suck reviving nectar food.

Their wings have tiny little scales
that overlap like slates or tiles –
and some are coloured, some the light
reflect – an iridescence bright.

But moths are mostly drab and fly
at night, unlike a butterfly.
And butterflies are rather thin;
at rest they often lift each wing.

Most moths instead are furry, fat,
with wings draped round or else fanned out
when resting. So, what is the best
and clearest difference, simplest test? –

It’s “do the feelers (though they don’t
sense touch or feel, but smell and scent)
end with a swollen tip, or not?”
for it they’re “clubbed”, then you have got

a butterfly; – or Burnet moth (!)
– the latter’s awkward as it both
is coloured and it likes the day –
but rests its wings the moth-like way!