Brooding in cocculiniform limpets (Gastropoda) and familial distinctiveness of the Nucellicolidae (Copepoda): misconceptions reviewed from a chitonophilid perspective

Small subunit rDNA and Bayesian inference reveal Pectenophilus ornatus (Copepoda incertae sedis) as highly transformed Mytilicolidae, and support assignment of Chondracanthidae and Xarifiidae to Lichomolgoidea (Cyclopoida)

“…This character effectively excludes the Chitonophilidae from the ‘splanchnotrophid group of families’, because the infective copepodid in members of this family bears four pairs of swimming legs. Such circumstantial evidence appears to substantiate a recent comparative study (Huys et al ., 2002) based on antennulary morphology and antennary segmentation, demonstrating that the Chitonophilidae cannot be placed in the poecilostome complex but should be regarded as a more basal cyclopoid lineage that established symbiotic relationships with mollusc hosts independently. Boxshall & Halsey (2004) also claimed that most families of the splanchnotrophid super‐familial grouping display an anthessiid‐like mandible, at least in the first copepodid, implying that the majority of mollusc‐associated poecilostome copepods are derived from a common myicolid/anthessiid ancestral stock.…”

“…It is therefore conceivable that males enter the duct as a small‐sized instar, and do not undergo their final moult and subsequent substantial increase in size until their arrival in the vesicle. A similar phenomenon has been reported in another mollusc parasite, Nucellicola holmanae Lamb, Boxshall, Mill & Grahame (Chitonophilidae), in which the adult male undergoes not only extreme transformation at the final moult but also gross size increase as a result of hypermorphosis (Huys et al ., 2002). Coincidently, the adult male of this species is also contained within a membranous vesicle (however, at the posterior end of the female), and the extent of hypermorphosis involved is evidenced by comparison with the exuvium size of the late copepodid (III) enclosed with it.…”

“…Instead, the poecilostomatoid taxa were resolved as a sister group to the Cyclopoida with moderately low bootstrap support (63%) but a high Bayesian posterior probability value (100%). This scenario does not necessarily conflict with the emerging morphology‐based concept of a paraphyletic Cyclopoida with the poecilostomatoid taxa being nested within this order (Huys et al ., 2002; Boxshall & Halsey, 2004), because in our study cyclopoids were represented only by the family Cyclopidae. Rather than analysing the data further, it seems obvious that inclusion of the more basal cyclopoid families Cyclopinidae, Notodelphyidae and Mantridae and denser sampling of the remaining ‘Poecilostomatoida’ are needed in an attempt to recover the paraphyletic status of the ‘gnathostome’ Cyclopoida, as their morphology would lead us to believe.…”

The anatomy of Lepetella sierrai (Vetigastropoda, Lepetelloidea): implications for reproduction, feeding, and symbiosis in lepetellid limpets

“…No diagnostic appendages or distinct organs associated with this mass were observed in the histological sections, so the identity of this parasite is unknown. However, it is possible that the observed instance of parasitism is an early stage of the parasitic chitonophilid copepods observed by other researchers in this species (Dantart & Luque 1994;Huys et al 2002), similar to the "vermiform endosome" stage seen in lepetodrilid limpets by Tunnicliffe et al (2008). Although the sections are not clear, there does appear to be a "rootlet system" Huys et al 2002) and what may be a small female body on the outside of the body wall.…”

“…War en (1972) reported brood protection in Lepetella cf. laterocompressa; however, the "brood" later turned out to be parasitic copepods (Huys et al 2002). Moskalev (1978) studied a large number of specimens (>180 of L. tubicola and 14 of T. lypidellaeformis) and even performed some histological sectioning, but did not report on lepetellid anatomy in detail.…”