Proofs for Proneomenia custodiens sp. nov.!

Today Christiane Todt and I got our proofs for our upcoming paper (Todt and Kocot in press, Polish Polar Research) describing a new species of Proneomenia I collected during the 2011 IceAGE cruise that broods its babies in its butt!

Here's the abstract:
During August-September 2011, scientists aboard the R/V Meteor sampled marine animals around Iceland for the IceAGE project (Icelandic marine Animals: Genetics and Ecology). The last sample was taken at a site known as “The Rose Garden” off northeastern Iceland and yielded a large number of two species of Proneomenia (Mollusca, Aplacophora, Solenogastres, Cavibelonia, Proneomeniidae). We examined isolated sclerites, radulae, and histological section series for both species. The first, Proneomenia sluiteri Hubrecht, 1880, was originally described from the Barents Sea. This is the first record of this species in Icelandic waters. However, examination of aplacophoran lots collected during the earlier BIOICE campaign revealed additional Icelandic localities from which this species was collected previously. The second represents a new species of Proneomenia, which, unlike other known representatives of the genus, broods juveniles in the mantle cavity. We provide a formal description, proposing the name Proneomenia custodiens n. sp. Interestingly, the sclerites of brooded juveniles are scales like those found in the putatively plesiomorphic order Pholidoskepia rather than hollow needles like those of the adults of this species. Cytochrome c oxidase subunit I (COI) DNA barcode sequences are provided for both species of Proneomenia.

Proneomenia custodiens n. sp. A. Photograph of a brooding specimen in the process of expelling its offspring, presumably a stress response (photo by D. Fiege); scale bar: 0.8 mm. B. Microphotography of one juvenile (photo by M. Błażewicz-Paszkowycz); scale bar: 100 µm. C. Histological cross-section through the mantle cavity (mc) of the holotype brooding juveniles (asterisks); one juvenile is situated in the mantle cavity opening (arrow); scale bar: 500 µm. D. Cross-section of a juvenile from within the mantle cavity of the holotype, showing the cerebral ganglion (cg), pharynx (ph), pedal ciliary pit (cp), and pedal gland of one of the juveniles. The specimen still contains yolk (y) and it is covered in cuticle and surrounded by the folded egg hull; scale bar: 50 µm.