Lagenopolycystis conglobata Schockaert and Artois 2025, sp. nov.

Lagenopolycystis conglobata Schockaert and Artois sp. nov. urn:lsid:zoobank.org:act: 742C9CE4-F1C8-4C3F-A6C9-BFC379775466 (Fig. 6) Lagenopolycystis sp. nov. 4 in Tessens et al. (2014) Diagnosis. Species of Lagenopolycystis with a robust prostate stylet of 71–130 µm (x̄ = 100 µm, n = 31), evenly curved over its whole length and with a blunt terminal end. The accessory stylet, attached at the very proximal end of the main stylet, is 52–123 µm (x̄ = 92 µm, n = 27), following the curve of the prostate stylet and closely stuck to it, giving the whole copulatory organ a conglobate aspect. The short straight tube of the ‘seminal receptacle’ is 3–4 µm long. Distribution. FRANCE • Bay of Marseille, Plateau des Chèvres, Amphioxus sand, 8–10 m deep (Leg. Dr M. Brunet, 3 February 1966) (TYPE LOCALITY) and near ‘La Pierre Joseph’ at the isle of Plane, fine sand, 17 m deep (collected by Dr M. Brunet, 7 July 1970); Banyuls-sur-Mer, Ile Grosse, ‘La Faille’, N42°28’57” E3°08’16”, clean, fine sand, 12 m deep (6 August 2007); Banyuls-sur-Mer, ‘l’Herbier’, 20–30 m left of end of pipes, N42°28’56” E3°08’09”, fine to medium sand with some silt, 10 m deep (2 November 2007); Cerbère, Canadells Islands, N42°26’52” E3°10’23”, sand mixed with much shell grit, 30 m deep (12 July 2023); Cerbère, Cap Peyrefite, N42°27’24” E3°10’15”, sand bottom alongside rock ledge, medium to coarse sand mixed with some shell grit, 20 m deep (14 July 2013); same locality, N42°27’23” E3°10’10”, clean fine sand, 18 m deep (13 July 2014); same location, N42°27’25” E3°10’17”, sand bottom alongside rock ledge, fine sand with some silt and debris of seagrass leaves, 22 m deep (12 July 2024); Peyrefite Bay, In the middle of the bay, N42°27’37” E3°09’32”, sand bank between seagrass beds, medium to coarse sand on top of ripple mark, 5 m deep (13 September 2019); Cerbère, ‘Les Chambres’, N42°26’31” E3°10’19”, sand area between seagrass beds, coarse sand mixed with some shell grit, 14 m deep (4 August 2014); same locality, N42°26’32” E3°10’20”, past the coastal rock zone, clean medium sand mixed with some fine shell grit, 19 m deep (27 May 2023); same locality, past the coastal rock zone, N42°26’33” E3°110’21”, clean medium sand mixed with some fine shell grit, 22 m deep (29 July 2024); Cerbère, Terrimbo, Les Aloès, in front of jetty, near railroad track, N42°27’11” E3°09’42”, fine gravel with some silt, 5 m deep (14 July 2011); same location, in front of jetty, past the coastal rock zone, N42°27’09” E3°09’47”, clean coarse sand mixed with some fine gravel, 8 m deep (8 September 2024); Cerbère, Terrimbo, middle of bay, N42°27’07” E3°09’59”, clean fine to medium sand on top of ripple mark, 20 m deep (31 July 2015); same locality, small rocky islands just south of municipal camping, N42°27’13” E3°09’55”, clean fine sand with some fine shell grit, 15 m deep and N42°27’13” E3°09’50”, fine sand with some silt, 15 m deep (18 May 2022); same locality, middle of bay, N42°27’07” E3°09’58”, fine sand mixed with some shell grit and silt, 19 m deep (9 September 2023); Cerbère, near harbour wall, N42°26’31” E3°10’04”, very fine sand with some silt, 3 m deep (11 September 2024). FRANCE, CORSICA • Bay of Calvi, western part of the bay in front of Pointe de la Revellata, N42°3’0” E8°4’3”, sand from 35 m deep (Leg. Dr P. Martens, 22 October 1982, 12 May and 25 November 1983). ITALY, SARDINIA • Punta Negra, sand with pebbles and a small amount of detritus, 30 cm deep (19 and 22 August 1994); Punta Tamburino, N41°0’1” E8°1’1”, channel among rocks, coarse gravel with silt, 29 m deep (29 September 2014). SPAIN • Portbou, l’Ocell, N42°25’58” E3°10’29”, clean medium sand mixed with much shell grit, 23 m deep (18 July 2011). Material examined. Thirty-two whole mounts, one of which designated the holotype (FMNH http://id.luomus. fi/KV. 546), one in the collections of SMNH (SMNH-54570), and the rest deposited as reference material in the collections of Hasselt University (HU XXIII. 3.44–HU XXIII.4.23). The stylet of one specimen (HU XXIII. 3.49) and the accessory stylet of five specimens (HU XXIII. 3.49; XXII.4.04, 12, 15, 16) could not be measured. Five serial sections (HU XXIII. 4.24–HU XXIII.4.28). Etymology. The species name refers to the conglobate and compact aspect of the copulatory organ. Conglobatus (Lat.): pressed tightly together. Additional remarks. Lagenopolycystis conglobata is the only species in which the accessory stylet follows the curve of the prostate stylet, lying tightly adjacent to it. This feature makes this species unmistakable.