SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c1f937b1c25facd7d7707c4f4fb42c0797d69ecc2684c01c0c1d38c611cdd51' 
  AND token = 'S4itKEE9rUC9qYe0IDnMRKONi3WVVD1H6dKSmt3jrMU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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