SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1d07d1ba31be2d1bd8167e9877367446868b8baa5442e702bf48fbcfba783c6' 
  AND token = 'FzpwbqjeTdww5GoENgkFu8nC+Hw4tVlIX+lKx1vHJbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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