SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e5a1b87b260ea045bf3d559b8d45d9f040ebd99e85526202cafc0aa4fc5ac4f' 
  AND token = 'dwVJlJAAHt+Xvgu2c5A0hNttnSXX99j42tCiJVXle50=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00112

JSON explain

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