SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58469ce1b996c09938e8be24f49ab562d83344149b49c75c6de6ea59bade5c72' 
  AND token = 'jdOWukOuj4PSxtdrFiRtvhfTOlzD6QT390DRQFjIHXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}