SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'ce3c2afc6005d997e6c604c9f4fff8000d64dbd932ea6d9a1cb05bef5c13bc4b' 
  AND token = 'rusH+dSe+vAa0Com9dpeti7XzAuvNHonkNL4AGwNLjE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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