Crenobiont, stygophile and stygobiont molluscs in the hydrographic area of the Trebisnjica River Basin Author Falniowski, Andrzej https://orcid.org/0000-0002-3899-6857 Department of Malacology, Institute of Zoology and Biomedical Research, Jagiellonian University, ul. Gronostajowa 9, 30 - 387 Krakow, Poland Author Lewarne, Brian The Devon Karst Research Society, Library & Office, 46, Morley Court, Western Approach, Plymouth, Devon, UK Author Rysiewska, Aleksandra Department of Malacology, Institute of Zoology and Biomedical Research, Jagiellonian University, ul. Gronostajowa 9, 30 - 387 Krakow, Poland Author Osikowski, Artur https://orcid.org/0000-0001-6646-2687 Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Krakow, al. Mickiewicza 24 / 28, 30 - 059 Krakow, Poland a.osikowski@urk.edu.pl Author Hofman, Sebastian https://orcid.org/0000-0001-6044-3055 Department of Comparative Anatomy, Institute of Zoology and Biomedical Research, Jagiellonian University, ul. Gronostajowa 9, 30 - 387 Krakow, Poland text ZooKeys 2021 2021-06-28 1047 61 89 http://dx.doi.org/10.3897/zookeys.1047.64034 journal article http://dx.doi.org/10.3897/zookeys.1047.64034 1313-2970-1047-61 835A7E2B82E845B09E3FB8548031A048 23C3761CE1BF5BFAA5301C213FB1D457 Iglicopsis butoti Falniowski & Hofman sp. nov. Fig. 9M-P GenBank no. COI: MW879273-MW879275; H3: MW865749-MW865751 Type materials. Holotype. Ethanol-fixed specimen (Fig. 9M ), Vrelo "Policki Studenac" (Crkvina); a cave spring in the left bank of and adjacent to the Trebisnjica River ( N 42.71288 , E 18.36514 ) (our locality 13, Fig. 4 ) close to Trebinje (Bosnia and Herzegovina), interstitially, 50 cm below the gravel floor of the spring; in the collection of the Department of Malacology of Jagiellonian University, voucher number ZMUJ-M.2651. Paratypes. Three paratypes destroyed to extract DNA, one specimen ethanol-fixed, in the collection of the Department of Malacology of Jagiellonian University, ZMUJ-M.2652. Diagnosis. Shell minute, ovate-conic, distinguishable from Montenegrospeum by a more oval habitus, broader spire and broader flat apex, sometimes showing scalarity at the body whorl; the penis with the left-side outgrowth located more proximally and bi-lobed, and additional flat outgrowth on the right side. Description. Shell (Fig. 9M-P ) up to 1.49 mm high and 0.55 mm broad, ovate-conic, whitish, translucent, thin-walled, and consisting of about five whorls, growing regularly and separated by moderately deep suture. Spire high and broad, apex broad and flat, body whorl less than 0.5 of the shell height, Aperture small, prosocline, oval in shape, peristome complete and thin, somewhat swollen, in contact with the wall of the body whorl, in some specimens showing scalarity close to the aperture, umbilicus slit-like. Shell surface smooth, with growth lines hardly visible. Measurements of holotype and sequenced and illustrated shells: Table 3 . Shell variability slight; scalarity and much bigger dimensions of one specimen (Fig. 9P ) most probably caused by the larval Trematoda (parasite gigantism). Table 3. Shell measurements (in mm) of holotype and sequenced and illustrated specimens of Iglicopsis butoti sp. nov. For explanation of the symbols a -β, see Fig. 13B .

-	Holotype	2F61	2F68	2F69
a	1.49	1.29	1.35	1.87
b	0.55	0.54	0.54	0.70
c	0.43	0.39	0.43	0.44
d	0.80	0.62	0.67	0.93
e	0.37	0.34	0.35	0.44
α	90	89	90	90
β	20	18	20	18

Soft parts morphology and anatomy . Body white, pigmentless, with no eyes. Ctenidium with nine short lamellae, osphradium elongated. Tectum forming a characteristic broad loop (Fig. 9N ). Female reproductive organs with unpigmented renal oviduct, bursa copulatrix and two small receptacula seminis; details unknown. The radula (Fig. 12 ) with the central tooth cusp formula: (4)3-1-3(4)1-1 or (5)4-1-4(5)1-1 Figure 12. Radula of Iglicopsis butoti , scale bars: 10 µm . Rather long and slender cusps grow regularly to central one. Lateral cusp with 5 - 1 - 5(6) long and massive cusps. Inner marginal tooth with ca 23 slender cusps of nearly invariable length along the tooth edge, outer marginal tooth with 26 broadly triangular cusps. Penis (Fig. 13A ) long, tapering, below the half of its length, proximally, bi-lobed outgrowth on the left side and flat outgrowth at the right side, at the distal part and the vas deferens well visible inside, running in zigzags. Figure 13. A Penis of Iglicopsis butoti , scale bar: 0.1 mm B shell measurements: a - shell height, b - body whorl breadth, c - aperture height, d - spire height, e - aperture breadth, α - apex angle, β - angle between body whorl suture and horizontal surface. Derivatio nominis. The genus name refers to the similarity of the shell to the moitessieriid genus Iglica Wagner, 1927. The specific epithet Iglicopsis butoti refers to the memory of Dr Louis J. M. Butot, a Dutch malacologist devoted mostly to the Greek malacofauna, good friend and the mentor of AF. Distribution and habitat. Known from the type locality only. Molecular relationships. despite its shell morphology, Iglicopsis clearly belongs to the Hydrobiidae Stimpson, 1865, Sadlerianinae Szarowska, 2006, and not to the Moitessieriidae Bourguignat, 1863 (Fig. 8 ). Its sister species is Montenegrospeum bogici in the H3 tree (Fig. 8 , bootstrap 95%), and on the tree based on both concatenated loci (but with bootstrap 63% only); in the COI tree the bootstrap does not support its phylogenetic position.