SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2244f199fd55dec32de304f414737daeaa7c5ca90501c731818446a54fc700c1' 
  AND token = 'WBpxYtLKCRipFwqiJtOuBQ1itGMIFGzOkUfk8+uisP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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