SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24fcee96f1815f4692d37c2eb4d78de2575226d9571066b51f0be64d53b3f6e1' 
  AND token = 'P9+gwdmLfF/Ud4zViD11kdBJsGxwPfJ898bjsnm+atU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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