Most individuals are between 4 and 10 mm, but smaller individuals would presumably have decayed before they could fossilize.
mˈoʊst ˌɪndᵻvˈɪdʒuːəlz ɑːɹ bᵻtwˌiːn fˈoːɹ ænd tˈɛn ˌɛmˈɛm, bˌʌt smˈɔːlɚɹ ˌɪndᵻvˈɪdʒuːəlz wʊd pɹɪzˈuːməbli hæv dᵻkˈeɪd bᵻfˌoːɹ ðeɪ kʊd fˈɑːsəlˌaɪz.