SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0ff485cf9c80da42aaaff2b688ad2d01a4d85eb2007991a804267a6d260e0210' 
  AND token = 'AkgrC7rtg9+8z5MF4VBELY/z15hwbFnEJIN/ZnCwLK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}