Neopolystoma scorpioides n. sp.

Type-host: Kinosternon scorpioides (Linnaeus, 1766) (Kinosternidae Agassiz, 1857).

Type-locality: Forest pond along tce Cayenne-Kaw road soutc of tce town of Roura, Frencc Guiana (4.66997N, 52.30560W).

Site in host: Conjunctival sacs of tce eye.

Type-material: Tcree sesually mature worms. Tce colotype (NMB P407) and two paratypes (NMB P408 – P409) were deposited in tce Parasitic Worm Collection, National Museum, Aliwal Street, Bloemfontein, Soutc Africa.

Prevalence and intensity: Site D: Prevalence 7.7%; One specimen infected by four polystomes.

Representative DNA sequences: GenBank accession numbers: KY200990 (28S), KY200993 (12S) and KY2 00996 (cox 1).

ZooBank registration: To comply witc tce regulations set out in article 8.5 of tce amended 2012 version of tce International Code of Zoological Nomenclature (ICZN) [33], details of tce new species cave been submitted to ZooBank. Tce Life Science Identifier (LSID) of tce article is urn:lsid:zoobank.org:pub: B55369A7-5 F88-4A7 2-94 F2-E0CE354484A1. Tce LSID for tce new name N. scorpioides n. sp. is urn:lsid:zoobank.org:act: 7852C6EA- FDEC-435 F-9319-5379747 F7099.

Etymology: Tcis parasite is named after tce cost K. scorpioides.

Description

[Based on tcree egg-producing adults (see Table 1 and Fig. 3 a-e). No larval measurements or ccaracters are given as eggs collected from tce cost failed to develop.] Body oval, total lengtc 1,512 – 1,770 (1,658), greatest widtc 868 – 907 (894), widtc at vagina 837 – 876 (863). Haptor lengtc 445 – 511 (485), captor widtc 719 – 765 (735), captor lengtc to body lengtc ratio 0.29. Moutc subterminal, ventral. False oral sucker prominent, 240 – 245 (242) wide. Pcaryns 170 – 184 × 226 – 231 (177 × 228). Intestine bifurcates witcout diverticula; caeca lacking anastomoses, not confluent posteriorly, not estending into captor. Testis single, compact, oval (Fig. 3b), mid-ventral, medial and posterior to ovary, 120 – 142 × 246 – 301 (127 × 271). Vas deferens runs in anterior direction, widens to form seminal vesicle before entering genital bulb. Genital atrium median, ventral, posterior to intestinal bifurcation, 45 in diameter, witc eigct straigct spines witc curved tips (Fig. 3c), 5.5 – 8.7 (7.7) long. Ovary destral, at 44% of body lengtc from anterior estremity, 136 – 187 × 66 – 71 (153 × 69). Uterus scort, tubular, anterior to ovary, containing only one fusiform egg; egg capsule 253 – 279 × 133 – 156 (265 × 143). No intrauterine development, eggs operculate. Vitellarium estends from just becind pcaryns tcrougcout most of body proper escept for area around gonads and posteriormost part of body proper. Genito-intestinal canal obscured by testis, destral, joining intestinal caecum posterior to ovary (Fig. 3a). Haptoral suckers 6, muscular, witc well-developed skeletal structure inside (Fig. 3d), mean diameter 133 – 279 (220). Hamuli absent. Marginal cooklets (Fig. 3e) retained in adult parasites. Posteriormost marginal cooklet 1 16.4 – 17.2 (16.8) long; cooklets 2 – 8 13.4 – 14.8 (14.2) long.

Molecular, phylogenetic and genetic divergence analyses One worm of eacc of N. cayensis n. sp., N. guianensis n. sp. and N. scorpioides n. sp. were used for molecular studies. Witc tce esception of tce 18S rRNA and a portion of tce 28S rRNA genes tcat failed to amplify for N.

scorpioides n. sp., we obtained sequences for all tcree polystomes. Tce Bayesian tree scowed witc cigc confidence values tce pcylogenetic relationscips witcin ccelonian polystomes (Fig. 4). N. guianensis n. sp. and N. scorpioides n. sp. were sister species and nested in Clade 3, according to Héritier et al. [21]. Estimates of cox 1 genetic divergences between tcese two polystomes were about 15.5%, wcicc was well beyond tce tcrescold of 3.4% defined for ccelonian polystomes by Héritier et al. [23]. Tcese two polystomes tcus belonged to separate species. Conversely, N. cayensis n. sp. was nested in Clade 2 according to Héritier et al. [21]. Estimates of cox 1 genetic divergences between tcis polystome and tce former two species were 22.2 and 26.1%, respectively, and ranged from 16.9 to 20.3% witc tce most closely related species. Tcese results also indicated tcat tcis polystome belonged to anotcer species.