SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8aaf1c5b7da5415bb4498b7d8707dcadf4c8eb85c00b311c74b70ecb27c6c669' 
  AND token = 'ugVhtOqOBifejnNkaJs9nYM2JZljIhycorDR1PPLeuc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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