Colour is not a species, and it never was
Black mold is a phrase rather than an organism. Dozens of genera present dark on a wall, and at least one of the ones people are most worried about is frequently a shade of olive or grey rather than black at all. Meanwhile a good deal of the dark staining people photograph and send us is not fungal growth: it is soot deposition from candles, ghosting along cold framing members, or dirt tracked by air moving through a gap.
What a laboratory can actually tell you about a black patch
A tape lift takes about thirty seconds. A clear adhesive is pressed to the growth, sealed, labelled and sent, and a microbiologist looks at the spores and the structures they are attached to. That is what settles the question, and it costs $85 including the analysis.
What comes back is a genus, and a note on whether the material shows active growth or only deposited spores. That distinction matters more than most people expect: spores that have merely settled on a surface came from somewhere else and tell you to keep looking, while structures that have actually colonised the material tell you the water is right there.
Here is the part that gets left out of most pages on this subject. Identification frequently does not change the work. Remediation practice does not vary much by genus: the water gets stopped, the affected porous material is removed under containment, and the area is cleaned and verified. A laboratory result naming Stachybotrys and one naming Cladosporium on the same square metre of wet drywall usually produce the same scope of work and the same price.
So we will tell you when to skip it. A small visible patch on a hard surface with a water source you have already found and stopped does not need a laboratory to confirm what you are looking at. Where identification genuinely earns its fee is when a landlord or an insurer disputes that there is growth at all, when the area is large enough that the scope will be argued over, or when the question is whether that staining is fungal in the first place.

What the job covers in Fort Lauderdale
What we cover
Identification of a visible dark growth by tape lift or swab, analysed by an accredited laboratory, with the moisture source traced at the same visit.
What you get
The genus named by a laboratory rather than guessed from its colour, the water it is living on identified, and the area measured so a remediation scope can be written against it.
Decision point
Whether identification changes anything. For a small patch with a source you have already stopped, it often does not, and we say so.