SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef9d82fe92706f2eb48872cac089007f6e98f2c92ada58a23a583fad91831d32' 
  AND token = 'ChcM31OJHxFsrxu2YQh3XYxYZP+4Er4KQXAHXxElV20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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