pectoral fin lepidotrichium Each pectoral lepidotrichium may be unsegmented (e.g., spine), segmented but unbranched (e.g., leading ray) or segmented and branched. Definition of lepidotrichium by Schultze and Arratia (1989: 217). For additional information about lepidotrichia see Arratia et al. 2001 and Arratia 2008. Lepidotrichium which is part of the pectoral fin, forming the pectoral fin skeleton and articulating with the pectoral radials. A pectoral lepidotrichium is composed of two hemitrichia that surround bundles of actinotrichia distally. TAO:0001551 VSAO:0000175 pectoral fin lepidotrichia pectoral fin ray teleost_anatomy true