SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8205cc1089f484e4b49b7102c69848f79530bc6eb3cb752b671773388397506f' 
  AND token = '5ljJEj6XiTSUlC2OV5Bdv9iM+1j7mq/7Yutf74L/xHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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