Eight New Species Of Ligophorus Euzet & Suriano, 1977 (Monogenea: Ancyrocephalidae) From Mugilids Off Peninsular Malaysia Author Lim, O. Y. M. Soo L. H. S. text Raffles Bulletin of Zoology 2012 2012-08-31 60 2 241 264 journal article 10.5281/zenodo.13256712 2345-7600 13256712 Ligophorus chelatus , new species ( Fig. 8i, 8A–G ) Type-host. — Liza subviridis Valenciennes Type-locality . — Off Carey Island , Banting , Malaysia ( 2°51'N , 101°22'E ) Type specimens . — Holotype : NHMUK 2012.7 .2.8 Paratypes : 5 paratypes NHMUK 2012.7.2.9– 13 in the Natural History Museum , London ; 3 paratypes ( ZRC .PAR.05) and 2 paratypes ( ZRC . PAR.08) in the Raffles Museum of Biodiversity Research , National University of Singapore ; 39 paratypes MZUM (P)2012.278(P)– 316(P) in the University of Malaya collection . Material studied . — 50 specimens studied; 50 specimens measured. Etymology . — This species is named after the claw-like accessory piece. Description . — Body elongate, 610 (382–801) 95 (52–134) (n = 50), pharynx size 31 (24–37) × 31 (24–35) (n = 30). Head-organs, eye-spots and alimentary system as in L. navjotsodhii , new species . Haptor well demarcated; size 92 (55–148) × 115 (63–165) (n = 50); 14 larval type marginal hooks, length 13 (11–16) (n = 50); two pairs of anchors; 2 dorsal anchors, inner length 38 (33–41) (n = 50), outer length 37 (30–40) (n = 50), inner root 14 (12–17) (n = 50), outer root 8 (6–10) (n = 50), point 6 (4–8) (n = 50); 2 ventral anchors, inner length 36 (32–39) (n = 50), outer length 38 (30–41) (n = 50), inner root 14 (11–16) (n = 50), outer root 9 (7–11) (n = 50), point 7 (5–10) (n = 50); 2 connecting bars: V-shaped dorsal bar, 34 (29–41) × 5 (4–7) (n = 50); ventral bar inverted W, 35 (29–40) × 8 (6–10) (n = 50), AMP with two membranous lateral pieces and raised median piece, distance between lateral pieces, 7 (5–11) (n = 50). Soft anatomical male reproductive system as in L. navjotsodhii , new species . Copulatory organ consists of copulatory tube, length 70 (59–80) (n = 50) with bilobed initial part and two opposing accessory pieces; an elongate groove piece 26 (21–31) (n = 50) and similar length non-groove piece with distal claw. Soft anatomical female reproductive system as in L. navjotsodhii , new species except vagina is sclerotised, vaginal opening median at level of recurved portion of ovary, vaginal tube sclerotised, length 34 (30–37) (n = 10), leading to ovoid seminal receptacle. Differential diagnosis . — Based on the PCA ( Fig. 2 ) and NT analyses ( Table 2 ), L. chelatus , new species is similar to L. navjotsodhii , new species in having anchors of similar shape and size and two opposing accessory pieces, but the two species are different in the distal end of the non-grooved part of the accessory piece; claw-like in L. chelatus , new species and hook-like in L. navjotsodhii , new species ( Figs. 8F , 7F ). L. chelatus , new species and L. navjotsodhii , new species are grouped with L. funnelus , new species in the PCA scatterplot ( Fig. 2 ) based on similarities in measurements of their anchors, bars and copulatory tube but L. chelatus , new species differs from L. funnelus , new species in having two opposing accessory pieces instead of the funnel-like accessory piece of L. funnelus , new species ( Figs. 8F , 9F ) and from L. navjotsodhii , new species in having a claw-like distal end instead of hook-like distal end of the non-grooved opposing accessory piece ( Figs. 8F , 7F ). The NT analyses grouped L. chelatus , new species with L. careyensis , new species based on similarities in the structure of the anchors, bars and accessory piece, with L. parvicirrus and L. minimus in the anchors and bars and with L. cephali , L. chabaudi , and L. mugilinu s in the structure of the anchors and AMP ( Table 2 ). However L. chelatus , new species differs from all these abovementioned species in having two opposing accessory pieces and from L. careyensis , new species in having the non-grooved opposing piece with a distal claw ( Fig. 8F ) instead of a distal fork ( Fig. 12F ).