P3Y4G2I1D2I1U1M3
17 points
PYGIDIUM is validvalid
the posterior region of certain invertebrates
in trilobites, the posterior division of the body, formed by fusion of the telson with one or more posterior pleurae
the posterior region of certain invertebrates
in trilobites, the posterior division of the body, formed by fusion of the telson with one or more posterior pleurae