Proceedings of 
the United States 
National Museum 
SMITHSONIAN INSTITUTION «© WASHINGTON, D.C. 
Volume 113 1962 Number 3459 
PLECTROTAXY AS A SYSTEMATIC CRITERION 
IN LITHOBIOMORPHIC CENTIPEDES 
(CHILOPODA: LITHOBIOMORPHA)! 
By Ravpew E. Crasity, Jr. 
Since 1862, when Ludwig Koch first employed plectrotaxic ? cri- 
teria, the number and disposition of the stout articular spurs of the 
lithobiid centipedes have played a major role in the systematics 
of the group and of the order to which it belongs. In that year Koch 
augmented his descriptions with notes on the ventral spurs of the 
ultimate legs. Proceeding along the same lines, Meinert in 1872 
noted the ventral spurs of the ultimate and first legs. In 1880 Latzel, 
responsible for so many innovations in the study of the Myriapoda, 
employed the dorsal and ventral plectrotaxy of the first, fourteenth, 
and fifteenth pairs of legs as correlative systematic criteria. C. H. 
Bollman in his short but prolific period of publication in the 1880’s 
followed Meinert and Koch. No doubt influenced by Latzel and 
Bollman, Chamberlin and Verhoeff at about the turn of the century 
embarked upon a relatively new phase of lithobiid systematics with 
their pronounced emphasis upon the plectrotaxy of all the legs as 
1 This study was undertaken with the aid of a grant from the National Science Foundation. 
2 Plectrotaxic, from plectrotaxy (rXexrpov=calcar=spur), the arrangement and nomenclature of 
the pedal spurs of lithobiomorphous centipedes. I devised and published this term many years ago be- 
cause other terms, e.g., Broelemann’s ‘‘spinulation,’’ were inappropriate in that they refer to spines. The 
difference between spines and spurs is important and worth stressing again. In accordance with the usage 
of Comstock, Snodgrass, and others, a spur is a movable multicellular alveolate outgrowth of the exoskele- 
ton. A spine by contrast is an immovable multicellular nonalveolate outgrowth of the exoskeleton. 
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