SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ed632acf4608e560c940efb4fa3ead16ba26e41bca707a05fdf0c84295d2f1d' 
  AND token = '+cnuBF2Q0h8jrudwtpCwynZlEJ8pLdqrJGj+Gkz6v6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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