Ligophorus johorensis, Oym & Wb & Lhs, 2015

Oym, Soo, Wb, Tan & Lhs, Lim, 2015, Three new species of Ligophorus Euzet & Suriano, 1977 (Monogenea: Ancyrocephalidae) from Moolgarda buchanani (Bleeker) off Johor, Malaysia based on morphological, morphometric and molecular data, Raffles Bulletin of Zoology 63, pp. 49-65 : 59-60

Ligophorus johorensis , new species

( Figs. 4C, D , 5G–L )

Type host. Moolgarda buchanani (Bleeker, 1853) .

Type locality. Straits of Johor, Peninsular Malaysia (01°2’6”N 103°5’4”E) .

Materials examined. All specimens collected from the Straits of Johor, Peninsular Malaysia. Holotype: NHMUK 2014.11 .10.1, coll. Liew Kim Seng, 19 December 2013 . Paratypes: NHMUK 2014.11.10.2–2014.11.10.3, ZRC. PAR.40– ZRC.PAR.42 and MZUM (P) 2014.39(P)– 2014.72(P), coll. Liew Kim Seng, 19 December 2013 .

Etymology. This species is named after the state of Johor, Peninsular Malaysia.

anchors, inner length 38 (35–41), outer length 34 (28–38), inner root 18 (15–21), outer root 9 (5–10), point 12 (10–13); two ventral anchors, inner length 40 (37–43), outer length 39 (35–42), inner root 19 (17–21), outer root 13 (10–14), point 9 (8–10); two connecting bars: dorsal bar broad V, 59 (52–74) × 5 (2–7); ventral bar inverted V, 51 (40–55) × 9 (6–13), AMP consists of two membranous lateral pieces and a raised median piece, distance between lateral pieces, 9 (6–11). Testis single, elongate, ovoid, postero-dorsal to ovary, spermatozoa observed in anterior region. Single elongate prostatic reservoir with prostatic duct leaving reservoir to enter bigger lobe of bilobed initial of copulatory tube. Male copulatory organ consists of copulatory tube, length 53 (46–60) with bilobed initial part and a simple grooved boat-like accessory piece, 30 (25–37). Ovary J-shaped with recurved posterior region; oviduct arises from anterior part of ovary. Vaginal opening and tube not observed. Vitellarium in lateral fields approximately co-extensive with intestinal caeca, confluent just posterior to intestinal bifurcation, just anterior to ovary and just posterior to cyclocoel.

Differential diagnosis. Ligophorus johorensis , new species, and L. kedahensis which possess anchors and accessory pieces of similar shape (anchors with long blade-like inner roots and a simple grooved boat-like accessory piece) are grouped closest in the NT analysis ( Fig. 2 ). However, L. johorensis , new species, and L. kedahensis differ in the length of the copulatory tube, the width of the dorsal bar and the morphology of the AMP. Ligophorus johorensis , new species, has a shorter copulatory tube and wider dorsal bar than L. kedahensis ; 53 (46–60) and 59 (52–74) in L. johorensis , new species, vs. 65 (57–75) and 51 (43–58) in L. kedahensis . In terms of the AMP, both species have raised median pieces but in L. johorensis , new species, the median piece is raised higher than in L. kedahensis and the distance between its membranous lateral pieces is shorter; 9 (6–11) in L. johorensis , new species, ( Fig. 5J ) and 12 (7–15) in L. kedahensis ( Soo & Lim, 2012) . Ligophorus johorensis , new species, is grouped closest to L. grandis , new species, in the PCA scatterplot ( Fig. 1 ) but can be differentiated from L. grandis , new species, in the morphology of the AMP; two lateral pieces and a raised median piece in L. johorensis , new species, ( Fig. 5J ) compared to a single bifurcating piece in L. grandis , new species ( Fig. 6D ). Ligophorus johorensis , new species, also closely resembles L. zhangi Dmitrieva, Gerasev, Gibson, Pronkina and Galli, 2012 in the general shape of its anchors, bars and male copulatory organ but it differs in the shape of the AMP of the ventral bar and length of the dorsal bar. Ligophorus johorensis , new species, has a raised median piece and a longer dorsal bar, 59 (52–74) compared to a flat median piece and shorter dorsal bar, 50µm and 52µm from two specimens of L. zhangi . Ligophorus johorensis , new species, is similar to L. simpliciformis in possessing morphologically similar ventral bars. However, L. johorensis , new species, differs from L. simpliciformis in having a longer male copulatory organ and accessory piece: 53 (46–60) and 30 (25–37) in L. johorensis , new species, vs. 43 (40–45) and 22 (20–23) in L. simpliciformis .

Figures

Fig. 4. Photomicrographs of the sclerotised hard parts Ligophorus liewi, new species (A & B), L. johorensis, new species (C & D) and L. grandis, new species (E & F). A, C & E, anchors and bars; B, D & F, male copulatory organ.

Fig. 5. Sclerotised hard parts of L. liewi, new species (A–F) and L. johorensis, new species (G–L): A & G, dorsal anchors; B & H, dorsal bar; C & I, ventral anchors; D & J, ventral bar (dorsal view); E & K, marginal hook; F & L, male copulatory organ.

Fig. 2. Dendrogram of 62 Ligophorus species based on characteristics of all hard parts (anchors, bars and copulatory organ). The arrows on the far right indicate the positions of the three new species: L. liewi, L. johorensis and L. grandis.

Fig. 1. Principal Component Analysis (PCA) scatterplot of 465 Ligophorus specimens based on all hard parts (marginal hook, anchors, bars and male copulatory organ). Vertical and horizontal bar plots indicate one-dimensional summary of the principal component axes, PC1 and PC2.

Fig. 6. Sclerotised hard parts of L. grandis, new species: A, dorsal anchors; B, dorsal bar; C, ventral anchors; D, ventral bar (dorsal view); E, marginal hook; F, male copulatory organ.