Ophiotaenia echidis, Chambrier & Alves & Schuster & Toma & Scholz, 2021
|
publication ID |
https://doi.org/ 10.1016/j.ijppaw.2021.03.006 |
|
persistent identifier |
https://treatment.plazi.org/id/03BB5422-FFD2-A670-B024-0FA9FCC67BB8 |
|
treatment provided by |
Felipe |
|
scientific name |
Ophiotaenia echidis |
| status |
sp. nov. |
3.1. Ophiotaenia echidis View in CoL n. sp. Figs. 1–3 View Fig View Fig View Fig
Type- and only host: Echis carinatus sochureki Stemmler, 1969 (Serpentes: Viperidae ).
Type-locality: Houbara Breeding Centre (25.10418; 55.11283), Dubai, United Arab Emirates GoogleMaps .
Other localities: Camel Reproduction Centre , Dubai (25.08752; 55.38819) GoogleMaps ; Dubai Safari (25.17971; 55.45056) GoogleMaps ; Emirates Industry for Camel Milk Products , Dubai (25.02290; 55.41492) GoogleMaps , all in the United Arab Emirates.
Prevalence: Six snakes of 20 examined (i.e., 30%) in March 2007, July 2014, July and December 2017, and June 2020 were positive.
Intensity of infection: A total of 58 tapeworms were found in six positive hosts, i.e., mean intensity of infection was 10 tapeworms/ infected host; minimum four tapeworms in June 2020, maximum 21 specimens in December 2017.
Site of infection: Small intestine.
Distribution: United Arab Emirates.
Type-material: Holotype MHNG-PLAT-0137383, 18 slides (complete whole-mounted specimen on three slides and 15 slides with serial sections) and two slides (with serial sections) IPCAS C-876 /1 from host field number UAE 04, Houbara Breeding Centre, collected in July 2017; one paratype MHNG-PLAT-0137384, 21 slides (one complete whole-mounted specimens on three slides and 18 slides with serial sections), and two slides (with serial sections) IPCAS C-876 /1 field number UAE 04, Houbara Breeding Centre (July 2017); two paratypes, IPCAS C-876 / 1 (two complete whole-mounted specimens on three and two slides, field number UAE 04- T2 a-3a), Houbara Breeding Centre (July 2017), all Emirates Industry for Camel Milk Products in Dubai, examined by R. Schuster in June 2020.
Other material: Vouchers MHNG-PLAT-120508 (paragenophores), 14 slides (seven slides with whole-mounted specimen and seven slides serial sections from host field number UAE 03, Dubai Safari; IPCAS C-876 / 1 (one whole-mounted specimen); MHNG-PLAT-88912, Houbara Breeding Centre (March 2007), one specimen without scolex, 17 slides (three whole-mount and 14 serial sections), field number UAE 01;
342
MHNG-PLAT-120507, one specimen without scolex, 35 slides (four whole-mounts and 31 with serial sections) Houbara Breeding Centre, field number UAE 02; MHNG-PLAT-0137385, Houbara Breeding Centre (July 2017) (one whole-mounted specimens without scolex, on two slides and 23 slides serial sections) and MHNG-PLAT-0137386, Houbara Breeding Centre (July 2017) (one whole-mounted specimens without scolex, on three slides), field number UAE 04, all from E. carinatus .
Etymology: The specific name is derived from the generic name of the host.
Representative DNA sequences and phylogenetic relationships: one isolate (MHNG-PLAT-120508) yielded partial lsr DNA (MW703700; 1489 bp long) and COI (MW703548; 921 bp long) sequences. The final alignment of only lsr DNA dataset comprised 1012 positions including 124 parsimony informative sites, whereas the concatenated alignment comprised 1615 positions (1012 of lsr DNA and 603 of COI) including 250 parsimony-informative sites. The trees resulting from the ML analyses of both single and concatenated datasets showed a strongly supported sister relationship between O. echidis n. sp. and Ophiotaenia lapata Rambeloson, Ranaivoson et de Chambrier, 2012 , from Madagascarophis colubrinus Schlegel ( Pseudoxyrhophiidae ) endemic to Madagascar ( Fig. 4 View Fig ) ( Rambeloson et al., 2012). The analysis of lsr DNA alone further shows these species within a polytomy (Clade Q) together with other proteocephalids from distantly related groups of snakes (families Elapidae , Pseudoxyrhophiidae , Pythonidae and Xenopeltidae ) from unrelated zoogeographical realms (Afrotropical, Australian, Madagascan and Oriental). While clade K of de Chambrier et al. (2015) is well supported (posterior probability = 1) in their analysis, our results show only weak support for this group ( Fig. 4 View Fig ) that encompasses, besides snake cestodes, the only proteocephalid from a mammal, Thaumasioscolex didelphidis Caneda-Guzm ˜´an, de Chambrier et Scholz, 2001, from the common opossum ( Didelphis marsupialis Linnaeus ) in Neotropical Mexico (Veracruz).
3.2. Description ( Figs. 1–3 View Fig View Fig View Fig )
(Based on four entire specimens and part of another two worms) Proteocephalidae . Large worms, 230–275 mm long, up to 1.2 mm wide, flattened dorsoventrally, with proglottids greatly elongated, up to 6.6 mm long. Strobila acraspedote, anapolytic, with 96– 105 immature proglottids (up to appearance of spermatozoa in vas deferens), 5–6 mature proglottids (up to appearance of eggs in uterus), 3–5 pregravid proglottids (up to appearance of hooks in oncospheres), 105–118 proglottids in total. Immature proglottids wider than long to longer than wide (length: width ratio 1: 0.5–6.0); mature, pregravid and gravid proglottids much longer than wide. Terminal proglottids much longer than wide ( Fig. 3 View Fig ), length: width ratio up to 1: 6.4. Tegument 7.5–10 thick.
Scolex spherical, aspinose ( Fig. 1A–C View Fig , 2A View Fig ), 190–450 long (measured from anterior extremity to posterior margin of suckers; x = 235, n = 3), 400–725 (x = 475, n = 3) wide, wider than neck, with four uniloculate, spherical suckers ( Fig. 1A–C View Fig , 2A View Fig ), 165–210 in diameter, representing 30–45% of scolex width; apical sucker or organ absent ( Fig. 2A View Fig ). Neck, i. e., unsegmented zone posterior to scolex to first recognisable proglottids elongate (up to 3.3 mm), up to 540 wide. Apex of scolex and luminal surface of suckers covered with capilliform filitriches ( Fig. 1D, G View Fig ); external (non-adherent) surface of suckers and between suckers covered with gladiate spinitriches ( Fig. 1E, I View Fig ); upper and lower rims of suckers and neck covered with gladiate spinitriches, interspersed with few capilliform filitriches ( Fig. 1F, H, J View Fig ).
Internal longitudinal musculature weakly developed, consisting of few narrow muscle fibres, more numerous along lateral margins of proglottid ( Fig. 2D View Fig ). Osmoregulatory canals run along vitelline follicles, sometimes overlapping them ( Fig. 2B View Fig ). Ventral canals, 10–20 in diameter, with numerous secondary canals directed externally. Dorsal canals thick-walled, 2.5–4 in diameter, situated alongside and median to vitelline follicles ( Fig. 2C, F, G View Fig ). Genital ducts run between osmoregulatory canals ( Fig. 2F and G View Fig ).
Testes spherical, 30–50 in diameter, 118–205 in number (x = 162, n = 20), in single layer and in two longitudinal columns on both sides of uterine stem, composed of single line of testes, situated at about 30% from lateral side of proglottids ( Figs. 2B View Fig and 3 View Fig ). Anteriorly, testes do not reach anterior margin of proglottids, starting at distance of 2–5% of proglottid length, i.e., slightly posterior to anterior-most vitelline follicles ( Fig. 3 View Fig ). Posteriorly, testes never reach ovary, with terminal testes at distance of 9–13% of proglottid length ( Figs. 2B View Fig and 3 View Fig ).
Vas deferens strongly coiled, reaching almost to mid-line of
343
proglottid, occupying very small area ( Fig. 2C, G View Fig , 3 View Fig ). Cirrus-sac ovoid, thick-walled, 220–290 long, i.e. 20–34% (x = 24%, n = 22) of proglottid width, 100–140 wide ( Fig. 2G View Fig ). Cirrus occupies 73–80% of length of cirrus-sac ( Fig. 2C View Fig ). Genital atrium narrow; genital pores irregularly alternating, slightly postequatorial to equatorial, situated at 49–61% (x = 56%, n = 21) of proglottid length ( Fig. 3 View Fig ).
Ovary small, bilobed, 370–540 wide, occupying 52–60% (x = 57%, n = 20) of proglottid width ( Figs. 2B View Fig and 3 View Fig ); relative size of ovary, i.e., ratio of surface of ovary to surface of proglottid (see de Chambrier et al., 2012), 1.1–1.6% of proglottid size. Ovary length represents 2.5–4.2% of proglottid length. Vagina predominantly anterior (79%), rarely posterior (21%, n = 24) to cirrus-sac, lined with intensely stained cells in its terminal (distal) part and surrounded by small circular sphincter (diameter of 70–80) near genital atrium ( Fig. 2C, F View Fig ). Mehlis’ gland 70–100 in diameter, representing 8–13% of proglottid width.
Vitelline follicles oval, very small (30–60 long, 30–60 wide), arranged in two lateral, longitudinal columns on dorsal side of proglottid ( Fig. 3 View Fig ), not interrupted on poral side dorsally at level of terminal genitalia (cirrus-sac and vagina – Fig. 2G View Fig ). Follicles not reaching anterior margin of proglottids ( Fig. 3 View Fig ); posteriorly, follicles may reach ovary,
344
345
occupying porally 89–94% and aporally 88–92% of proglottid length, respectively.
Primordium of uterine stem ventral, with 47–55 (x = 50, n = 8) lateral branches (diverticula) on each side ( Fig. 3B View Fig ), never reaching posteriorly beyond ovarian isthmus ( Fig. 2B View Fig ). Formation of uterus of type 1 of de Chambrier et al. (2004) as follows: Uterine stem present as undifferentiated longitudinal median concentration of chromophilic cells in immature proglottids. In mature proglottids, uterine stem straight, occupying almost entire length of proglottids. Lumen appears in first mature proglottids. Lateral branches formed when eggs appear in uterus. Thin-walled lateral branches grow in pregravid and gravid proglottids ( Fig. 3B View Fig ), occupying up to 72% of proglottid width, and opening by elongate, slit-like uterine pore.
Eggs large, oval to spherical, with thin, hyaline outer envelope, up to 120 (n = 12) in diameter, somewhat collapsed in distilled water ( Fig. 2E, H, I View Fig ). Inner envelope consists of trilayered embryophore, with thick external layer, 44–53 in diameter, and nucleated envelope of irregular shape, 40–49 in diameter. Oncosphere surrounded by additional thick layer, 20–23 in diameter; oncospheres spherical, 11–12 in diameter, with 3 pairs of embryonic hooks 5–6 long ( Fig. 2E, H, I View Fig ).
346
| R |
Departamento de Geologia, Universidad de Chile |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
|
Kingdom |
|
|
Phylum |
|
|
Class |
|
|
Order |
|
|
Family |
|
|
Genus |