Fungal culture medium can be used for positive identification of the species. The fungi tend to grow well at 25 degrees Celsius on Sabouraud's agar within a few days to a few weeks. In the culture, characteristic septate hyphae can be seen interspersed among the epithelial cells, and the conidia may form either on the hyphae or on conidiophores. Trichophyton tonsurans, the causative agent of tinea capitis (scalp infection) can be seen as solidly packed arthrospores within the broken hairshafts scraped from the plugged black dots of the scalp. Microscopic morphology of the micro- and macroconidia is the most reliable identification character, but both good slide preparation and stimulation of sporulation in some strains are needed. While small microconidia may not always form, the larger macroconidia aids in identification of the fungal species.