POLYCHAETOUS ANNELIDS 



Part VIII. Pilargiidae 



(Plates 59-63) 



By Olga Hartman 



The family Pilargiidae (including the Kynephoridae Ehlers, 1920) 

 was erected by St. Joseph (1899) for a single species, Pilar gis verrucosa 

 St. Joseph from littoral zones in France. The first species of the family,^ 

 however, was Ancistrosyllis groenlandica Mcintosh (1878) from deep 

 water off Greenland but this was originally referred to the family 

 Syllidae. A year later Webster (1879) described 2 species, Phronta 

 tardigrada and Cabira incerta from Virginia, placing them in uncertain 

 positions. The first of these has since been referred to Ancistrosyllis but 

 the second remains enigmatical. In 1893 Korschelt found a pelagic 

 larval pilargiid off Trieste, Italy which he named Harpochaeta cingulata, 

 but this has since been referred to Ancistrosyllis. In the years since then 

 a few additional records of this unique family have appeared but their 

 occurrence in collections has been extremely rare. The pilargiids, as 

 known today, still represent a small, unusual group. The few known 

 genera are aberrant in their relations to one another, perhaps because 

 they represent relict species. Since most of them are small and easily 

 overlooked, it is also likely that more intensive search will reveal others. 



Although a separate family has been erected for these species, there 

 has been disagreement among specialists as to their actual status. Some 

 authors, notably Fauvel (1920 and 1923), Monro (1933) and Berkeley 

 (1941) have regarded them as aberrant hesionids. Hessle (1925, p. 9) 

 has shown that Ancistrosyllis is neither a syllid nor a hesionid as defined 

 today. Hessle stressed the following characters as unique to Ancistro- 

 syllis : ( 1 ) the relative massiveness of the palpi as compared with the 

 small prostomial lobe, (2) the inarticulate condition of the paired anten- 

 nae, (3) the posterior position of the median antenna, (4) the asetigerous 

 condition of the peristomial segment, (5) the inconspicuous nature of 



^Siffambra grubit MuIIer (1858, Arch. Naturgesch., vol. 24.1, pp. 214-215, pi. 6, 

 figs. 7-9) from Santa Catharina, Brazil, known only through a brief, original 

 account, seems to be an Ancistrosyllis, belonging to the group with long cirri. If 

 its status can be more clearly verified from topotypes, a change in nomenclature 

 may be desired, since the name Sigambra Miiller predates Ancistrosyllis Mcintosh. 

 Another name, Otopsidae Ditlevsen (1917, Danish Ingolf Exped., vol. 4, pt. 4, 

 pp. 67-69) erected for Otopsis longipes Ditlevsen, from off southwest Ireland in 

 843 fms, is also to be referred to the family Pilargiidae, but since the palpi were 

 not described, the generic status, whether Pilargis or Ancistrosyllis, cannot be 

 ascertained. 



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