Emerging global novelty in phyllobothriidean tapeworms (Cestoda: Phyllobothriidea) from sharks and skates (Elasmobranchii)
Caira, Janine N.
Bueno, Veronica
Jensen, Kirsten
Zoological Journal of the Linnean Society
2021
2021-02-17
193
1336
1363
8TG4K
Caira & Bueno & Jensen, 2021
Caira & Bueno & Jensen
2021
[265,570,1545,1568]
Cestoda
Phyllobothriidae
Rockacestus
GBIF
Animalia
Phyllobothriidea
18
1359
Platyhelminthes
species
carvajali
sp. nov.
( FIGS 7, 8A–E) ZooBank registration: C1BE31F7-1E16-4A24-920B- E42B5796066E. Description(Based on two whole mature worms, three whole immature worms, and three scolices examined with SEM.) Worms euapolytic, craspedote, 13.1–14.5 mmlong; proglottids 75–81 intotal number; maximum width at level of scolex. Scolex consisting of four bothridia, 546–903 (774 ± 165; 4) long, 900– 1146 (1049 ± 104; 5) wide. Bothridia folded ( Figs 7A, 8A), with apical sucker and single loculus, 406–648 (509 ± 104; 4; 7) long, 378–753 (552 ± 134; 4; 7) wide when folded, sessile anteriorly, free posteriorly; loculus with marginal loculi and posterior depression bounded by circular band of muscle fibres ( Fig. 7B); apical sucker 84–155 (118 ± 21; 5; 15) long, 85–154 (116 ± 21; 5; 16) wide; posterior depression 126–214 (156 ± 36; 3; 7) long, 132–199 (165 ± 30; 3; 7) wide. Cephalic peduncle lacking. Neck 5.2–6.7 mmlong. Distal surface of apical sucker and anterior portions of loculus with papilliform filitriches ( Fig. 8B); distal surface of posterior depression with lingulate spinitriches and papilliform filitriches ( Fig. 8C). Proximal bothridial surface with papilliform filitriches ( Fig. 8D). Neck ( Fig. 8E) and strobila with capilliform filitriches arranged in wide scutes. Immature proglottids wider than long, becoming longer than wide with maturity, 71–76 innumber ( Fig. 7C). Mature proglottids wider than long ( Fig. 7D), becoming longer than wide posteriorly ( Fig. 7E), four or five in number. Terminal proglottid 1143–1424 long, 537–540 wide, length-to-width ratio 2.1–2.6:1. Testes 46–55 (50 ± 4; 4; 4) in total number, nine to 12 (10 ± 1; 4; 4) in number in post-poral field, 38–53 (47 ± 5; 2; 6) long, 64–83 (74 ± 8; 2; 6) wide. Vas deferens coiled medial to cirrus sac. Cirrus sac oval, 302 long, 132 wide, thin walled, containing coiled cirrus; cirrus armed with spinitriches. Genital pores irregularly alternating, 73–79% of proglottid length from posterior end; genital atrium shallow. Vagina weakly sinuous, extending from ootype along midline of proglottid to anterior margin of cirrus sac, then laterally along anterior margin of cirrus sac to open into common genital atrium anterior to cirrus. Ovary at or near posterior margin of proglottid, H-shaped in frontal view, 344–406 long, 182–252 (217 ± 50; 4) wide, tetralobed in cross-section; ovarian margins lobulate. Vitellarium follicular; follicles arranged in two lateral bands that converge medially; each band consisting of multiple columns of follicles, extending throughout length of proglottid, partly or fully interrupted by terminal genitalia, uninterrupted by ovary; follicles highly variable in form. Excretory vessels 4, arranged in one dorsal and one ventral pair on each lateral margin of proglottid. Gravid proglottids not observed. Typehost:Yellownose skate, Dipturus chilensis(Guichenot, 1848)( Rajiformes: Rajidae de Blainville).
Typelocality: Pacific Oceanoff Puñihuilon the island of Chiloé, Chile( 41°55′43″S, 74°02′16″W). Additional locality: Pacific Oceanoff Niebla, Los Rios, Chile( 39°51′S, 73°24′W).
Site of infection:Spiral intestine.
Type material: Holotype(mature worm, MNHNCLno. PLAT-15023); two paratypes(one mature worm, USNMno. 1638652; one immatureworm, USNMno. 1638653); two paratypes(immature worms, LRPnos 9770 and 9771), three paratypes(mature worm SEM vouchers, LRPnos 9773–9775). Sequence data:GenBank accession MW419973, hologenophore (CHL-76-5; VB136) LRPno. 8913.
Etymology:This species is named for Chilean parasitologist Dr Juan Carvajal, without whose assistance with the logistics, our fieldwork in Chile, which led to collection of the typematerial of this species, would not have been possible.
Remarks: Rockacestus carvajaliis the smallest member of the genus, with a total length of 13.1– 14.5 (vs. 15–33, 170, 60–170, 50, 26–58, 50–140, 36–62 and 90 mmin Ro. arctowskii, Ro. brittanicus, Ro. georgiensis, Ro. piriei, Ro. radioductus, Ro. rakusai, Ro. siedleckiiand Ro. williamsi, respectively). It further differs from all of these species except Ro. georgiensisand Ro. pirieiin possessing bothridia that are highly, rather than moderately, folded. It possesses fewer testes per proglottid than both of the latter species (47 vs. 140–190 and 150, respectively).
3414928301
Chile
Chiloe
-41.92861
Pacific Ocean
19
-74.03778
Punihuil
18
1354
1
holotype
3414928314
Chile
-39.85
Pacific Ocean
1166
-73.4
Niebla
18
1354
1
Los Rios
3414928318
MNHNCL, USNM, LRP
21
1357
4
1
holotype