SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdc74efee1a8f1675aa54431d7fd1593e33dac6df7e48846f34e7c3d49e5c791' 
  AND token = 'TJg9jwJw3Dy3ddMwxSFCK4QWoZUWmcqAXiGOBKWvZq0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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