Heteralepas PilSbry 1907

Heteralepas Pilsbry, 1907

Heteralepadids with ctenopod cirri, inner rami of V & VI atrophied. Type species, Alepas rex Pilsbry, 1907.

Remarks. Species of Heteralepas are generally considered to have ctenopod or lasiopod cirri used for setose filter feeding, while Paralepas has acanthopod cirri, generally used to feed on the food or tissues of their hosts, including the eggs of hosts such as spiny lobsters (cf. Newman et al. 1969: Fig. 103, 2a ctenopod, 4 lasiopod, 5 acanthopod). The two genera are further distinguished by the inner rami of the posterior two pairs of cirri (V and VI), which are similar to the outer rami in Paralepas but conspicuously reduced in length and breadth in Heteralepas (Nilsson- Cantell 1921).

Heteralepas quadrata (Aurivillius, 1894) has lasiopod cirri, but the inner rami of cirri V and VI have sub-equal rather than very unequal rami. Furthermore, as noted by Buhl-Mortensen & Newman (2004), the species not only has an exceptionally wide geographical range for a heteralepadid, but it has since been observed that two samples from Mexico, considered to be H. quadrata, can be distinguished by their cyprid larvae (Celis et al. 2008), perhaps foreshadowing a new genus.