In geophilomorph centipedes, the overall shape invariance does not mir
ror the widespread variability in segmental composition (intra-and int
erspecific, linked or not with sex differences). We have developed a m
orphometric approach to this puzzling mismatch by studying allometric
patterns in ontogeny and segmental patterns of metric traits of sterna
and appendages, as well as through a comparative evaluation of morpho
logical complexity. Comparisons of segmental patterns from individuals
with different number of body segments (N) show that both the overall
shape of the trunk and the segmental distribution of morphological ma
rkers are independent from N. Therefore, segments per se are of little
significance as homologues. In Clinopodes flavidus C.L. Koch, 1847 (G
eophilidae), size and shape of the leg-bearing trunk are in allometric
relationship to the size of the N-invariant terminal body parts; this
relationship is independent from N, that is, size and differentiation
of trunk structures are independent from the number of segments. In a
macroevolutionary perspective, a quantitative approach to morphologic
al complexity of metameric structures reveals both increases and decre
ases in complexity of centipede trunk structures.