SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66de4d4ff2d753f1d190956977c229cdbfceed842f72a9b9b3e02d7213e55568' 
  AND token = 'Xub/33ww9L0VBpZ/ezOOnMPR7URpcgKkdMLQiG0cxDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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