Three new species of Heth Cobb, 1898 (Ransomnematoidea: Hethidae) from spiroboloid millipedes from Mexico

Abstract

Heth gordae n. sp., H. xarochae n. sp. and H. tuxtlensis n. sp. from the intestine of spiroboloids from Mexico are described herein. Females of H. gordae n. sp. and H. xarochae n. sp. can be differentiated from all other described species of Heth from the Americas by the presence of two sets of lateral spines with multiple cusps with a common broad base arranged in a semilunar shape pattern. Heth gordae n. sp. exhibits a narrower pattern that resembles more a comb-like structure, whereas H. xarochae n. sp. exhibits a broader pattern. Both aforementioned species resemble H. hexaspinosum from Panamá, but the latter possesses fewer spines without a common base. Lateral spines with multiple cusps have never been previously described in the genus Heth. Females of H. tuxtlensis n. sp. resemble Asian collar lappet-species but differ from them in possessing a complete uninterrupted collar with indented single lateral lappets. Specific characters described herein set these species apart from the Caribbean Heth species, most South American, and those previously described from Mexico. The present descriptions increase the number of Heth species recorded from Mexico from three to six.