Brain architecture of the largest living land arthropod, the Giant Robber Crab Birgus latro (Crustacea, Anomura, Coenobitidae): evidence for a prominent central olfactory pathway?

Table 1 Morphometric analysis of olfactory compartments

Brain compartment	Neuropil	Neuropil volume (μm³)	Proportion of the total neuropil volume (%)	Cell cluster	Nucleus diameter (μm)	Cell counts
Entire brain		2,849,638,500	100	-	-	-
Protocerebrum	HN - hemiellipsoid body neuropil	191,421,900	13.4	5	5.55	253556
Deutocerebrum	ON - olfactory neuropil	374,681,700	26.3	9/11	6.74	89808
Deutocerebrum	AcN - accessory neuropil	500,693	0.04	10	5.43	162250

Means of olfaction-related neuropil volumes, estimated cell counts and ranges of cell nucleus diameters for corresponding cell clusters are summarized here. All values, except the percentage of the neuropil volume to the total neuropil volume of the entire brain, refer to means of a single brain hemisphere of Birgus latro.

ISSN: 1742-9994