Protoancylodiscoides yombai Bassock Bayiha, Bahanak & Bilong Bilong, 2024

Protoancylodiscoides yombai Bassock Bayiha, Bahanak & Bilong Bilong View in CoL , sp. nov.

Fig. 4 View Figure 4

https://zoobank.org/ 7CC0A832-309A-438F-8333-6CBA6B46EC0C

Type host and locality. Chrysichthys nigrodigitatus ( Siluriformes : Claroteidae ), the Sanaga River in Edéa ( Cameroon), 3°47’43.25”N and 10°08’12.18”E.

Other locality. The Dibamba in Douala, 3°55’31”N, 9°40’21”E GoogleMaps .

Infection site. Gill lamellae.

Type material. Holotype RMCA _VERMES_44350 ; Paratypes RMCA _VERMES_44351-44352 .

Description based on five individuals. Dorsal anchors with long and thick inner root, ending by trunk-like structure, outer root quite non-existent, blade arched at its base but ending in point, thick filament covers middle section of blade. Dorsal bar in chevron, slightly curved, with hole at each extremity where small extension folds towards front face of bar. Ventral anchors, smaller than their dorsal counterparts, with narrow outer root shorter than inner one, lenticular fenestration at base of each inner root, hull and thick filament less sclerotised; blade with thin and short point. Ventral bar V-shaped made up of two arms joined medially. Presence of seven pairs of hooks in three types according to their shape, size and position. Latero-ventral hooks II, V, VI, VII of similar shape and size [i.e. thin, without shank (= distal subunit)], resemble those present in ancyrocephaline oncomiracidia (larval hook). They correspond to proximal subunit (= outer root +thumb+point) in Kritsky and Kulo (1999); medio-ventral hook pairs I and IV enlarged with thick and long shank; latero-dorsal hooks III with moderately developed shank; presence of dorsal structure in shape of elongated amphora with sclerification in its central part (onchuim). Presence in haptor of dorsal onchium longer than wide. Male copulatory organ consists of long tubular penis associated with accessory piece made up of two subunits: one as an irregular structure with ridges, and the second one a massive plate. Vagina presenting one coil at its base, turns around at its distal extremity which is in form of calyx.

The measurements of the parasite in toto, the haptor and the copulatory sclerotised parts are shown in Table 1.

Etymology. yombai refers to Mr. André Pierre Yomba for his invaluable contribution in fish collection.

Remarks. Protoancylodiscoides yombai sp. nov. is close to P. edeaensis sp. nov., P. mansourensis and P. chrysichthes by the morphology of ventral bar, ventral anchors, dorsal onchium and hooks. However, it differs from these species by: (1) morphology of vagina with a turn of whorl at distal part before calyx in P. yombai sp. nov., while well coiled at base in P. mansourensis , and looped (1 turn) in P. chrysichthes ; (2) morphology of onchium, that of P. yombai sp.nov. is in shape of elongated amphora with sclerification in its central part while that of P. edeaensis sp.nov. is in shape of flared amphora; (3) the size of some sclerotised parts, mainly: (i) dorsal anchor a = 76 (75–78) i n P. yombai sp. nov. vs a = 93 (87–97) i n P. edeaensis sp. nov, a = 88 (81–93) i n P. mansourensis and a=64 (55–69) i n P. chrysichthes ; (ii) dorsal bar x=38 (36–39) in P. yombai sp. nov. vs x = 48 (45–53) i n P. edeaensis sp. nov, x = 45 (40–48) in P. mansourensis and x = 41 (34–46) in P. chrysichthes ; (iii) ventral anchor x=34 (32–36) in P. yombai sp. nov. vs x = 48 (46–51) in P. edeaensis sp. nov and x = 44 (39–47) in P. mansourensis ; (iv) penis length =152 (136–168) in P.yombai sp. nov. vs 249 (222–278) i n P. edeaensis sp. nov, 325 (302–347) in P. mansourensis and 255 (162–365) in P. chrysichthes .