Calidris is a genus of Arctic-breeding, strongly migratory wading birds in the family Scolopacidae. 
The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for some grey-coloured waterside birds.

1/ Spoon-billed sandpiper (Rẽ mỏ thìa, Calidris pygmaea)

2/ Curlew sandpiper (Rẽ bụng nâu, Calidris ferruginea)
The specific ferruginea is from Latin ferrugo, ferruginis, "iron rust" referring to its colour in breeding plumage.

3/ Red-necked stint (Rẽ cổ hung, Calidris ruficollis) 
The specific ruficollis is from Latin rufus, "red" and collum, "neck".

4/ Sanderling (Rẽ cổ xám, Calidris alba) 
The name derives from Old English sand-yrðling, "sand-ploughman".
The specific, alba, is Latin for "white".

5/ Sharp-tailed sandpiper (Rẽ đuôi nhọn, Calidris acuminata)
The specific acuminata is from Latin acuminatus, 'sharp, pointed'.

6/ Ruff (Rẽ lớn, Calidris pugnax)
formerly placed in different genera and was known as: Tringa pugnax, Philomachus pugnax
The specific epithet refers to the aggressive behaviour of the bird at its mating arenas — pugnax from the Latin term for "combative".

7/ Great knot (Rẽ lớn ngực đốm, Calidris tenuirostris)
The specific tenuirostris is from Latin tenuis "slender" and rostrum "bill".

8/ Temminck's stint (Rẽ Lưng đen, Calidris temminckii)
The specific epithet is from the name of a Dutch naturalist Coenraad Jacob Temminck.

9/ Red knot or just knot (Rẽ lưng nâu, Calidris canutus)

10/ Broad-billed sandpiper (Rẽ mỏ rộng, Calidris falcinellus)
The specific name falcinella is from falx, falcis, "a sickle. 
Some research suggests that it should rather go into the genus Philomachus.

11/ Long-toed stint (Rẽ ngón dài, Calidris subminuta) 
The specific subminuta is from Latin sub, "near to" and minuta, "small" from its similarity to the little stint, Calidris minuta.

12/ Little stint (Rẽ nhỏ, Calidris minuta or Erolia minuta)
The specific minuta is Latin for "small.

13/ Dunlin (Rẽ trán trắng, Calidris alpina)
formerly placed in the genus Erolia.
The specific alpina is from Latin and means "of high mountains", in this case referring to the Alps.
The English name derives from dun, "dull brown", with the suffix -ling, meaning a person or thing with the given quality.

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