Glossidiella peruensis, Huancachoque & Sáez & Cruces & Mendoza & Luque & Chero, 2020

Huancachoque, Eva, Sáez, Gloria, Cruces, Celso Luis, Mendoza, Carlos, Luque, José Luis & Chero, Jhon Darly, 2020, Glossidiella peruensis sp. nov., a new digenean (Plagiorchiida: Plagiorchiidae) from the lung of the brown ground snake Atractus major (Serpentes: Dipsadidae) from Peru, Zoologia (e 38837) 37, pp. 1-6 : 2-5

Glossidiella peruensis sp. nov.

http://zoobank.org/ 69E8EDC9-8672-464C-A389-DF93F0246D42

Figs 1–12

Type host. Atractus major Boulenger, 1894 ( Dipsadidae ), brown ground snake. Sites of infection. Lung. Type locality. Highway Fernando Belaúnde Terry (6°11’S, 76°50’W) near the Mayo river, Moyobamba, San Martin region, Peru. Intensity. 10 specimens found in a single snake examined. Type material. Holotype ( MUSM 4029 ); 6 paratypes ( MUSM

4030a-f).

Description. Based on 7 whole mounted specimens and 2 SEM prepared specimens. Body elongate, slender, tapering posteriorly and markedly enlarged in anterior fifth of body, 12.78–14.56 (13.75; n = 7) mm long, 1.07–1.40 (1.11; n = 8) mm wide at level of ventral sucker. Length/width ratio 10.40–12.53 (11.40):1. Tegument spined ( Figs 1, 5); spines almost imbricated, with central groove and curved distal tip ( Figs 10–11), 16–19 (17; n = 2) long, directed posteriorly. Numerous small button-like papillae irregularly distributed on the dorsal edge of the oral sucker region ( Figs 5). Forebody 11.56–16.22 (14.55; n = 6) mm long, occupying 9.1–12.6% (11.1%; n = 6) of body length. Oral sucker subterminal, muscular, 640–787 (719; n = 7) long, 760–998 (829; n = 7) mm wide, 4.7–5.1% (4.9%; n = 6) of body length, 66.4–71.3% (69.4%; n = 7) of maximum body width, substantially larger than ventral sucker ( Figs 1, 5, 7). Prepharynx short. Pharynx subspherical, muscular, surrounded by numerous gland cells densely grouped ( Fig. 1), 280–465 (333; n = 7) long, 320–449 (381; n = 7) wide. Esophagus short. Intestinal bifurcation in midforebody, 1.07–1.32 (1.12; n = 7) mm from anterior end. Intestinal ceca slightly sinuous anteriorly or not, of unequal length, terminate at posterior region of body ( Fig. 1). Ventral sucker ovate, 600–723 (655; n = 7) long, 590–770 (662; n = 7) wide, in anterior third of body, 4.8–5.7% (4.9%; n = 7) of body length, 52.1–60.1% (55.4%; n = 7) of maximum body width. Oral sucker width to ventral sucker width ratio 1.19–1.32 (1.26):1. Testes entire, distinctly ovate, tandem, sometimes oblique, in middle third of body ( Fig. 1); anterior testis 600–900 (746; n = 6) long, 380–510 (436; n = 6) wide, posterior testis 660–854 (743; n = 5) long, 420–501 (474; n = 5) wide; distance between testes 1.32–1.88 (1.56; n = 6) mm long, occupying 9.3–13.7% (11.9%; n = 6) of body length; post-testicular region 3.22–5.96 (5.11; n = 6) mm long, occupying 27.6–44.2% (38.5%; n = 6) of body length. Cirrus sac oblong ( Fig. 2), 1.630 –2.041 (1.809; n = 7) mm long, 240–333 (270; n = 7) wide, situated longitudinally between anterior margin of ventral sucker and at 190–460 (304; n = 5) from anterior margin of ovary; contains tubular, coiled seminal vesicle and unarmed cirrus; cirrus muscular with papillated internal surface ( Figs 8–9). Prostatic cells fill available space outside seminal vesicle and ejaculatory duct ( Fig. 2). Genital pore immediately anterosinistral to ventral sucker ( Figs 1, 2, 5). Ovary rounded, entire, submedian, 430–500 (456; n = 7) long, 370–457 (400; n = 7) wide; distance between ovary and anterior testis 1.03–1.81 (1.33; n = 7) mm long, occupying 7.8–12.8% (10.1%; n = 7) of body length. Seminal receptacle almost reniform ( Figs 1, 3), post-ovarian, 105–212 (174; n = 7) long, 99–215 (140; n = 7) wide. Laurer’s canal not observed. Vitellaria in form of numerous bunch-like clusters of small follicles, intercecal, cecal and extracecal, extending from post-ovarian zone to near end of ceca ( Fig. 1). Uterus intra- and extracecal, passes between testes and occupies most of post-ovarian part of hindbody ( Fig. 1). Egg small, ovoid, operculated, thin shelled ( Fig. 4), 24–30 (26; n = 7) long, 13–17 (15; n = 7) wide. Excretory vesicle not observed. Excretory pore terminal, at middle line of posterior end of body ( Fig. 12).

pg

Etymology. The specific epithet refers to the country where the species was found.

Remarks. Based on the presence of an unarmed genital pore at the level of the ventral sucker and the absence of an external seminal vesicle, the new species belong to the Plagiorchiidae Lühe, 1901 ( Tkach 2008). It is assigned to Glossidiella as it exhibits the following combination of morphological features: tegument with spines; ventral sucker in anterior third of the body; a long cirrus sac, containing a coiled seminal vesicle; a genital pore immediately anterosinistral to the ventral sucker; vitelline follicles forming numerous bunch-like clusters on either side of the body extending from the ovary to near the cecal extremities; and an intra and extracecal uterus that passes between the testes and occupies most of post-ovarian part of hindbody ( Tkach 2008). Glossidiella is a monotypic genus and was originally proposed for a digenean species, G. ornata Travassos, 1927 found in the lung of the false water cobra, Hydrodynastes gigas (Duméril, Bibron & Duméril, 1854) (= Cyclagras gigas ) ( Dipsadidae ) in Brazil ( Travassos 1927, 1928, Tkach 2008, Fernandes and Kohn 2014). Glossidiella peruensis sp. nov. is readily separated from G. ornata by its oblong cirrus sac, rather than being claviform as in G. ornata and by having button-like papillae on the dorsal edge of the oral sucker that are absent in G. ornata (present study; based on type materials). Furthermore, the testis of G. peruensis sp. nov. are distinctly ovate and well separated from each other, whereas they are rounded and near to each other in G. ornata . Finally, Glossidiella peruensis sp. nov. possesses substantially wider oral (66.4–71.3% vs 36.2–42.1% of maximum body width) and ventral suckers (52.1–60.1% vs 30–38.2% of maximum body width).