Haliotrema sanchezae, Cruces & Chero & Sáez & Luque, 2017

Cruces, Celso L., Chero, Jhon D., Sáez, Gloria & Luque, José L., 2017, Dactylogyrids (Monogenea) parasitic on marine fish from Peru including the description of a new species of Haliotrema Johnston & Tiegs, 1922 and two new species of Parancylodiscoides Caballero & C. & Bravo-Hollis, 1961, Zootaxa 4311 (1), pp. 111-121 : 112-115

Haliotrema sanchezae n. sp.

( Figs. 1–8 )

Type-host: Scarus perrico Jordan & Gilbert ( SCaridae ), bumphead parrotfish.

Site of infection: Gill filaments.

Type locality: Puerto PiZarro , Tumbes, Peru (45°54'S, 81°05'W), South AmeriCa.

Prevalence: 2 of 4 hosts infeCted (50%) with a total of 12 worms.

Mean intensity of infection: 6 monogeneans per infeCted host (range 5–7).

Specimens deposited: Holotype, MUSM 3471; 8 paratypes, MUSM 3472–3479; 3 paratypes, CHIOC 38853a, b, C.

Etymology: This speCies is named in honor of Prof. Lidia SánCheZ PéreZ (National University of San MarCos, Peru) for her Contribution to the study of helminth parasites of Peruvian vertebrates.

Description: Based on 3 speCimens mounted in Gray and Wess medium and 9 fiXed in 4% hot formalin and stained with Gomori’s triChrome. Body elongate ( Fig. 1 ), 0.900–1.370 (1.121; n = 12) mm long; greatest width 221–305 (251; n = 12) usually at midbody length. Tegument smooth. CephaliC region broad; CephaliC lobes poorly developed; 3 bilateral pairs of ConspiCuous head organs; bilateral pair of CephaliC glands at postpharyngeal level. Eye-spots absent; aCCessory ChromatiC granules few, sCattered in CephaliC area. PharynX subspheriCal, with maXimum width 71–99 (79; n = 10); esophagus short; intestinal bifurCation postpharyngeal; intestinal CeCa unite posteriorly to gonads, laCking divertiCula. PedunCle broad, elongate. Haptor slightly differentiated from body proper, almost reCtangular, 98–140 (114; n = 8) long; 119–189 (152; n = 8) wide; ventral eXtrinsiC adduCtor musCle developed, ConneCted to small, lateral, half-moon-shaped sClerotised pieCe near tip of superfiCial root of ventral anChors ( Fig. 2 ). AnChors with fine ConspiCuous alae ( Figs. 3–4 ). Ventral anChor 85–109 (97; n = 5) long, with well elongate superfiCial root, knob-like deep root, straight shaft, short point ( Fig. 3 ); base 27–31 (34; n = 5) wide. Dorsal anChor 85–88 (87; n = 5) long, slightly fenestrated, with elongate superfiCial root, well-developed deep root, Curved shaft, Curved point ( Fig. 4 ); base 32–37 (35; n = 5) wide. Ventral bar 70–90 (80; n = 5) long, X-shaped, with anterior and posterior projeCtions direCted laterally, anterior projeCtions widened ( Fig. 5 ). Dorsal bar 74–88 (81; n = 5) long, mask-shaped, elongate, anterior margin trilobed and lateral ends enlarged, rounded ( Fig. 6 ). Fourteen similar hooks, 14–16 (15; n = 7) long, eaCh with depressed thumb, slender shank and deliCate point ( Fig. 7 ); filamentous hook (FH) loop about shank length. Male Copulatory organ (MCO) 181–232 (198; n = 9) long, tapered, tubular; Cylinder-shaped base, 45–77 (60; n = 9) long, terminating in diagonal opening; aCCessory pieCe membranous, blanket- shaped, lying dorsal to MCO, enveloping from proXimal Copulatory tube to terminal portion of MCO ( Fig. 8 ). Testis ovate, interCeCal, postequatorial, 113–160 (141; n = 7) long, 79–125 (96; n = 7) wide; seminal vesiCle small, fusiform, sinistrolateral to MCO; single elongate prostatiC reservoir, deXtrolateral to MCO; prostatiC glands ConspiCuous, interCeCal, surround distal region of MCO. Ovary 68–111 (84; n = 6) long, 78–122 (96; n = 6) wide; subspheriCal, slightly overlapping testis. Vaginal aperture deXtromarginal; vaginal vestibule pyriform slightly lying diagonally to midline, proXimal end sClerotised; vaginal duCt narrow, running posteriorly to join small inConspiCuous seminal reCeptaCle. OviduCt, ootype and uterus not observed. Vitelline folliCles dense throughout trunk, absent in regions of reproduCtive organs. Eggs not observed.

Remarks: Haliotrema Johnson & Tiegs, 1922 was proposed by Johnston & Tiegs (1922) to aCCommodate speCies possessing a haptor armed with two pairs of anChors (ventral and dorsal), eaCh joined by a transverse bar; eyespots laCking; intestinal CeCa ending blindly and vas deferens not looping around the left CeCum. Haliotrema australe Johnston & Tiegs, 1922 from the gills of blaCk-spotted goatfish, Parupeneus spilurus (Bleeker) (Mullidae) , in Australia was designated as the type speCies. Yamaguti (1963) reeXamined the holotype of H. australe and notiCed that the vas deferens loops around the left CeCum. Subsequently, Young (1968) amended the generiC diagnosis and defined Haliotrema based on the Combination of the following CharaCteristiCs: (1) vas deferens looping around the left intestinal CeCum, (2) CeCa Confluent posterior to gonads and (3) the deXtral opening of the vagina.

Currently, 11 speCies of Haliotrema have been desCribed as having a male Copulatory organ of similar struCture to H. sanchezae n. sp. (tapered and tubular with a membranous aCCessory pieCe): H. bodiani Yamaguti, 1968 from the Tarry hogfish, Bodianus bilunulatus (LaCepède) (Labridae) , in Hawaii; H. cirrhitusi MendoZa-FranCo & Violante-GonZaleZ, 2011 from the giant hawkfish, Cirrhitus rivulatus ValenCiennes (Cirrhitidae) , in the MeXiCan PaCifiC; H. conspecta Zhukov, 1980 from the redtail parrotfish, Sparisoma chrysopterum (BloCh & SChneider) ( SCaridae ), in the Gulf of MeXiCo; H. cornutum ( MiZelle & Kritsky, 1969) from the spotfin hogfish, Bodianus pulchellus (Poey) (Labridae) , in Cuba; H. lactophrys ( MaCCallum, 1915) Vala, Maillard & Overstreet, 1982 from the sCrawled Cowfish, Acanthostracion quadricornis (Linnaeus) (OstraCiidae) , in a New York Aquarium, United States; H. ornatum Yamaguti, 1941 from unidentified apogonid in Japan; H. pacificum ( MiZelle & Kritsky, 1969) from the blaCknosed butterflyfish, Johnrandallia nigrirostris (Gill) (Chaetodontidae) , in the MeXiCan PaCifiC; H. priacanthi Yamaguti, 1968 from the glasseye snapper, Heteropriacanthus cruentatus (LaCepède) (PriaCanthidae) , in Hawaii; H. scari Young, 1968 from the rivulated parrotfish, Scarus rivulatus ValenCiennes (SCaridae) , in Australia; H. tuberobaculum Zhukov, 1980 from the striped parrotfish, Scarus iseri (BloCh) (SCaridae) in the Gulf of MeXiCo and H. xesuri Yamaguti, 1940 from the sCapel sawtail, Prionurus scalprum ValenCiennes (ACanthuridae) , in Japan. From them, only three speCies have been desCribed from sCarid fish, i. e., H. conspecta , H. scari and H. tuberobaculum .

Haliotrema sanchezae n. sp. most resembles H. conspecta and H. tuberobaculum by the morphology of the male Copulatory organ (tapered-shaped Cirrus tube, Cylinder-shaped base and a blanket-shaped aCCessory pieCe). However, H. sanchezae n. sp. is distinguished from H. conspecta by its dorsal bar whiCh is broadly mask-shaped with its anterior margin trilobed and lateral ends rounded (elongated with lateral digitiform alae eXpansions and anterolateral margin with two ConiCal protuberanCes in H. conspecta ). In addition, H. sanchezae n. sp. differs from H. conspecta by the siZe of the male Copulatory organ (181–232 in the new speCies vs 137–150 in H. conspecta ).

The new speCies differs from H. tuberobaculum in its well-developed superfiCial roots of the ventral anChors (short superfiCial rots of the ventral anChors in H. tuberobaculum ). Also, the ventral bar of H. sanchezae n. sp. is Xshaped (M-shaped in H. tuberobaculum ). Furthermore, the male Copulatory organ of H. sanchezae n. sp. is bigger than that of H. tuberobaculum (181–232 in the new speCies vs 57–61 in H. tuberobaculum ).

Haliotrema sanchezae n. sp. Can be distinguished of H. scari by the morphology of the male Copulatory organ that is tapered and tubular with a blanket-shaped aCCessory pieCe (tubular and strongly Curved with an aCCessory pieCe like a flap in H. scari ). Also, Haliotrema sanchezae n. sp. and H. scari Can be also easily distinguished by the morphology of the anChors and transverse bar.

Haliotrema sanchezae n. sp. differs from H. bodiani , H. cirrhitusi , H. cornutum , H. lactophrys , H. ornatum , H. pacificum , H. priacanthi and H. xesuri by having a membranous aCCessory pieCe suCh as blanket enveloping a part of the male Copulatory organ (filamentous, membranous aCCessory pieCe enCirCling male Copulatory organ to form Complete spirals in the other eight speCies) and a half-moon-shaped sClerotised pieCe near tip of superfiCial root of ventral anChors (absent in the other eight speCies). In addition, Haliotrema sanchezae n. sp. differs from H. bodiani , H. cirrhitusi , H. cornutum , H. lactophrys , H. ornatum , H. pacificum , H. priacanthi and H. xesuri by the morphology of the anChors and transverse bars.

Figures

FIGURES 1 – 8. Haliotrema sanchezae n. sp. 1. Whole Worm (Ventral). 2. Half-moon-shaped sclerotIzed pIece. 3. Ventral anchor. 4. Dorsal anchor. 5. Ventral bar. 6. Dorsal bar. 7. Hook. 8. Male copulatory organ.