Lagenopolycystis peresi ( Brunet, 1965 ) Artois & Schockaert, 2000

Monnens, Marlies, Schockaert, Ernest R., Diez, Yander L., Revis, Nathalie, Janssen, Toon, Jouk, Philippe E. H., Tessens, Bart, Van Steenkiste, Niels W. L. & Artois, Tom J., 2025, On the genus Lagenopolycystis Artois and Schockaert, 2000 (Platyhelminthes, Kalyptorhynchia, Polycystididae), Zootaxa 5659 (3), pp. 357-376 : 361-363

Lagenopolycystis peresi ( Brunet, 1965) Artois & Schockaert, 2000

( Fig. 2 )

Emended diagnosis after Brunet (1965). Species of Lagenopolycystis with a prostate stylet of 68–103 µm (x̄ = 86 µm, n = 21) curved over its whole length for almost 180° and with a rounded end; both ‘walls’ of the gutter are proximally ear-shaped with a highly thickened rim. The accessory stylet is 32–64 µm (x̄ = 46 µm, n = 21), slightly curved and attached between the middle to the proximal 1/3 of the wall of the prostate stylet. The tube of the ‘seminal receptacle’ is about 20 µm and slightly spiralling.

Distribution. FRANCE • Gulf of Marseille, Plateau des Chèvres, N43°12’11” E5°21’54”, sand and gravel under the influence of bottom currents or Amphioxus sand, patch surrounded by a very nearby seagrass bed, with organic input from Marseille’s sewage discharged nearby, 10 m deep (Leg. Dr M. Brunet, May–June 1964) (TYPE LOCALITY); Gulf of Marseille, between Île Plane and Île Riou, N43°11’09” E5°22’48”, same sediment type on a rocky substrate, but with less organic material and much finer shell debris, 20 m deep (Leg. Dr M. Brunet, May–June 1964).

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) ; Peyrefite Bay , N42°27’37” E3°09’34”, in the middle of the bay, sand bank between seagrass beds, clean fine sand, 6–7 m deep (16 September 2019) ; Cerbère , ‘ Les Chambres’, N42°26’29” E3°10’22”, close to rocks in front of a cave, clean, coarse-grained sand mixed with fine gravel, 4 m deep (15 July 2007) ; same locality, N42°26’30” E3°10’20”, sand area between rocks, coarse sand mixed with gravel, shell grit, and debris of seagrass leaves, 5–6 m deep (25 July 2014) ; same locality, N42°26’30” E3°10’21”, sand area between rocks, coarse sand mixed with gravel, 5–6 m deep (16 July 2015) ; same locality, N42°26’31” E3°10’20”, past the coastal rock zone, clean fine sand, 17 m deep (2 August 2015) ; same locality, N42°26’33” E3°10’21”, past the coastal rock zone, clean fine sand mixed with some shell grit, 22 m deep (11 July 2023) ; Cerbère , Terrimbo, Les Aloés, N42°27’11” E3°09’43”, in front of the jetty, approximately 50 m seawards, fine-grained sand with some silt, 5 m deep (11 July 2007) ; same locality, N42°27’11” E3°09’43” at foot of rock forming a little island on the left side of the jetty, clean coarse sand mixed with gravel, 5 m deep (19 July 2012) ; same locality, N42°27’09” E3°09’48”, in front of jetty, past the coastal rock zone, clean fine sand, 9 m deep (5 August 2014) ; same locality, N42°27’12” E3°09’42”, at foot of rock forming a little island on the left side of the jetty, medium sand to fine gravel with some larger stones and debris of sea grass, 5–6 m deep (26 August 2016) ; Cerbère , small bay just outside the harbour, N42°26’28” E3°10’13”, fine sand mixed with some shell grit and some silt, 12 m deep (6 September 2024) .

FRANCE, CORSICA • Bay of Calvi , western part of the bay in front of Pointe de la Revellata, N42°35’04” E8°43’34”, sand from 35 m deep (Leg. Dr P. Martens, 12 April 1984) .

ADRIATIC SEA • Amphioxus sand at an unspecified locality (Dr T. Karling in Brunet, 1965).

ITALY, SARDINIA • Alghero, Calabona beach, in front of bar Quintilio next to Hotel Calabona , N40°32’39” E8°19’13”, algae on rocks in small bay (28 March 2010) ; Punta Negra , algae from rocks on a small beach sheltered from the sun (19 August 1994) ; same locality, sand from gully, 30 cm deep (22 August 1994) ; same locality, algae on rocks near small jetty (20 June 2007) .

SPAIN • Portbou , small rock island just south of the harbour, N42°25’29” E3°10’17”, fine sand mixed with some shell grit and some silt, 22 m deep (19 July 2021) .

Material examined. Twenty--six whole-mounted specimens on 25 slides, including four specimens from the SMNH collections that were part of the material of the original description [ SMNH nr. 52945 and 54926 (with two specimens)–54927], the others deposited in the collections of the UHasselt (HU XXIII.2.23– HU XXIII.2.44). Five of those were in too bad shape to be measured. Five serially sectioned specimens, including the holotype (SMNHType nr. 3044) and paratype (SMNH-Type nr. 5913), the other three deposited in the collections of the Uhasselt (HU XXIII.2.45– HU XXIII.2.47) .

Additional remarks. Brunet (1965) mentions a relative proboscis length of 1/4 of the body length, but in our specimens the length was almost about 1/5 of the body length. The morphology of the stylets of the newly collected specimens conforms to the original description by Brunet (1965). The robust prostate stylet, curved over its whole length, and with its ‘earlike’ proximal ends of the gutter, makes this species easy to recognise and distinguishes it from the other species of Lagenopolycystis (see additional remarks on L. azorensis sp. nov. and L. poena sp. nov.). The record of L. peresi from Sweden is highly questionable: Brunet (1965) cited this record based on a photograph provided by Dr T. Karling. However, we have a whole mount in our collection labelled L. peresi , collected in the Skagerrak by Karling, which is, in fact, L. poena sp. nov. Details regarding the locality on the label can be found under that species (see further). Thus, Brunet’s (1965) record of L. peresi from Sweden should rather be attributed to L. poena sp. nov.

Figures

FIGURE 2. Lagenopolycystis peresi A–C. Camera lucida drawings of the stylets of reference material (A, C: SMNH-54926, 2 specimens; B. HU XXIII.2.37), with A. also including a depiction of the sclerotised tube adjacent to the entrance of the ovo-vitelloduct, highlighting the strong sphincter at its base. D–E. Drawings of stylets from newly collected material from the Mediterranean (D: HU XXIII.2.30, E: HU XXIII.2.29, F: specimen lost, G: HU XXIII.2.26). All stylets are drawn to the same scale. H. Micrograph of the stylet of a reference specimen (SMNH-54927). I–L. Micrographs of a live specimen from Sardinia (now HU XXIII.2.31), including I. an overview of the entire specimen, J. the proboscis, K. the pharynx, and L. the stylet.