وإما مفصل وهو ما ذكر وجهه
One type is detailed: the respect of resemblance is explicitly mentioned.
In “Zayd resembles a lion in courage,” the speaker specifies the shared quality. The audience need not guess whether the comparison concerns courage, physical appearance or something else.
Mufaṣṣal depends on stating the shared respect. Whether the simile marker appears is another classification, and whether its terms are single or composite is yet another. A single expression may belong to several divisions at once because they answer different questions.