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Macrogyrodactylus clarii Gussev, 1961 Figs. 2A–C, 3A,D (i); Table 4 T y p e h o s t: Clarias sp. (Siluriformes: Clariidae). T y p e l o c a l i t y: Lake Awasa, Ethiopia. O t h e r r e c o r d s: Clarias gariepinus: Egypt – El-Naggar and Serag (1987), El-Naggar (1993), Hagras et al. (1995, 1999), El-Naggar et al. (1997, 2001a,b, 2004a,b, 2016, 2017, 2019, 2020), El-Naggar and Cable (2007), Arafa et al. (2009, 2012), Radwan et al. (2009), El-Seify et al. (2011), Mashalay et al. (2019); Ethiopia – Gussev (1961), Beletew et al. (2016); Ghana – Paperna (1969, 1979); Kenya – Barson et al. (2010); Nigeria – Obiekezie and Ajah (1994), Eyo et al. (2015); South Africa – Khalil and Mashego (1998), Olivier et al. (2009), Madanire-Moyo et al. (2010, 2012), Matla (2012), Mahlatji (2014); Uganda – Paperna (1979); Zimbabwe – Barson et al. (2008, 2010), Madanire-Moyo and Barson (2010). Clarias anguillaris (Linnaeus); Nigeria – Shotter (1980). L o c a l i t i e s (p r e s e n t s t u d y): SouthAfrica: KuShokwe Pan, Ndumo Game Reserve, KwaZulu-Natal Province; Zambia: Barotse floodplain, Zambezi River, Northwestern Province. S i t e o f i n f e c t i o n: Skin and gills. Vo u c h e r m a t e r i a l: Twenty-three voucher specimens deposited in NMB (Coll. Nos. P 800–809, 820–822). R e p r e s e n t a t i v e D N A s e q u e n c e s: 710–753 bp long sequences of the ITS1-5.8S-ITS2 region of the rRNA gene of four isolates (GenBank accession numbers: MZ869846, MZ869850, MZ869847, MZ869849). Hologenophores: NMB (P 824–827). S p e c i m e n s s t u d i e d: n = 48 (KuShokwe Pan, South Africa - SA); n = 25 (Barotse floodplain, Zambia - ZM). I n f e c t i o n r a t e: KuShokwe Pan (SA): Prevalence (P) of 80% and intensity of infection (IF) 1–12; Barotse floodplain (ZM) P = 64%, IF = 1–4. Morphological observations (measurements provided in Table 4): Morphology of haptoral sclerites conform to description of Gussev (1961) and redescription of El-Naggar and Serag (1987). Individuals armed with 16 marginal hooks, two positioned in anterolateral lobes, 14 in posterior edge of haptor. Basal part of sickle has small indentation near anterior end of base, anterior end of sickle base thin, sharply rounded. Base of sickle rounded with slight curvature on distal side into slender sickle blade curving inward and tapering into a fine, sharp point that stops in line with anterior end of sickle base (see Figs. 2B, 3D (i)). Hamulus complex consisting of a pair of robust hamuli with curvature into point, sharp inward curved root, small dorsal bar consisting of two articulating sclerites, Y-shaped ventral bar with short anterolateral processes and long posterior central arm. Two narrow rod-like sclerites (R1 and R2) accompany ventral bar (Figs. 2A–C, 3A). Cirrus observed in 24 (SA) and 11 (ZM) specimens studied, each armed with 13–15 small spines and one large spine (Fig. 2C). Abbreviations: KY – Kenya; SN – Senegal; SA – South Africa; ZM – Zambia; n – number of specimens studied. Remarks. The dimensions of the hamulus (total length and length of the shaft, root and point) from specimens studied from NGR (SA) and Barotse floodplain (ZM) (Table 4) are similar to those of specimens from the Middle Letaba Dam (SA) and localities in Kenya and Egypt (El-Naggar and Serag 1987, Khalil and Mashego 1998, Barson et al. 2010). Dimensions obtained for the dorsal bar in the present study do not deviate from the ranges found in other studies. Marginal hook size also conforms to previously recorded measurements. The marginal hook sickle morphology is identical to that illustrated for M. clarii specimens collected from Zimbabwe and M. clarii × Macrogyrodactylus heterobranchii from Kenya (see Barson et al. 2010). Gussev (1961) and El-Naggar and Serag (1987) reported 16 and 12 cirrus spines, with one large spine in their descriptions, respectively. Additionally, this study provides details on the morphology of the sickle, which was not described by Gussev (1961) and El-Naggar and Serag (1987). Comparative measurements are presented in Table 4.

Truter, Marliese, Acosta, Aline A., Weyl, Olaf L. F., Smit, and Nico J. (2021): Novel distribution records and molecular data for species of Macrogyrodactylus Malmberg, 1957 (Monogenea: Gyrodactylidae) from Clarias gariepinus (Burchell) (Siluriformes: Clariidae) in southern Africa. Folia Parasitologica (027) 68: 1-14, DOI: 10.14411/fp.2021.027, URL: http://dx.doi.org/10.14411/fp.2021.027

Macrogyrodactylus congolensis (Prudhoe, 1957) Yamaguti, 1963 Figs. 2D–F, 3B,D (ii); Table 5 S y n o n y m: Neogyrodactylus congolensis Prudhoe, 1957 T y p e h o s t: Clarias gariepinus (Burchell) (Siluriformes: Clariidae). T y p e l o c a l i t y: Lake Upemba (Lualaba River), Democratic Republic of the Congo. O t h e r r e c o r d s: Clarias gariepinus: Egypt – El-Naggar et al. (1999, 2001a,b, 2004b, 2007, 2017, 2019), Hagras et al. (1999), Arafa (2000, 2011), Arafa et al. (2003, 2013, 2014), Mashalay et al. (2019); Democratic Republic of the Congo – Prudhoe (1957), Vanhove et al. (2018); Kenya – Barson et al. (2010); South Africa – Khalil and Mashego (1998), Madanire-Moyo et al. (2010, 2012); Uganda – Thurston (1970), Akoll et al. (2012). Clarias anguillaris: Senegal – Přikrylová and Gelnar (2008), Barson et al. (2010). L o c a l i t i e s (p r e s e n t s t u d y): South Africa: Vaal River, North West Province and Usuthu River, Ndumo Game Reserve (NGR), KwaZulu-Natal Province; Zambia: Barotse floodplain, Zambezi River, Northwestern Province, Kabompo River, Northern Province. S i t e o f i n f e s t a t i o n: Skin and gills. Vo u c h e r m a t e r i a l: Nineteen voucher specimens deposited in, NMB P 812–817, 823. R e p r e s e n t a t i v e D N A s e q u e n c e: 696 bp long sequence of the ITS1-5.8S-ITS2 region of the rRNA gene of one isolate. GenBank accession number: MZ869848. Hologenophore, NMB P 828. S p e c i m e n s s t u d i e d: n = 25 (Vaal River, SA), n = 2 (Usuthu River, SA), n = 1 (Barotse floodplain, ZM), n = 1 (Kabompo River, ZM). I n f e c t i o n r a t e: Usuthu River (SA): P = 3%, IF = 1; Vaal River (SA): P = 33%, IF = 1–109; Barotse floodplain (ZM): P = 6%, IF = 1; Kabompo River (ZM): P = 50%, IF = 1. Abbreviations: SA – South Africa; ZI – Zimbabwe; ZM – Zambia; n – number of specimens studied. Morphological observations (measurements provided in Table 5): Morphology of haptoral sclerites similar to illustrations provided in description of Prudhoe (1957). Hamulus complex of M. congolensis large in size, has slender hamuli less sharply curved into point and root, armed with 16 marginal hooks. Marginal hook sickle robust, with noticeable curvature in base near anterior end of sickle. Anterior end of sickle base rounded and convex, with indentation on distal side as it joins sickle blade that is short, curved inward tapering into a fine point and stops before the proximal end of sickle base (Figs. 2E, 3D (ii)). Hamuli complex has small uniform dorsal bar, wider than long, Y-shaped ventral bar with long anterolateral processes, and short posterior central arm. Two narrow rod-like sclerites accompany ventral bar (Figs. 2D–F, 3B). Cirrus observed in one specimen from the Usuthu River (SA) and Barotse floodplain (ZM), respectively, and 17 individuals from the Vaal River (SA), each armed with 18–20 small spines and one large spine (Fig. 2F). Remarks. The dimensions of the hamulus (total length and the length of the shaft, root and point) from specimens studied from the Vaal and Usuthu rivers (SA) and the Kabompo River and Barotse floodplain (ZM) are similar in size to specimens from the Middle Letaba Dam and Lake Turkana in Kenya (Khalil and Mashego 1998, Barson et al. 2010). Macrogyrodactylus congolensis specimens from Senegal seems to have smaller hamuli compared to the present and other studies (see Přikrylová and Gelnar 2008). Dimensions obtained for the undivided dorsal bar in the present study do not deviate from the ranges found in other studies. Marginal hook measurements are also in accordance with previously recorded measurements (see Table 5). The morphology of the marginal hook sickle conforms to those illustrated for M. congolensis from Kenya (see Barson et al. 2010). Prudhoe (1957) reported fewer cirrus spines (15), with one large spine in his description of M. congolensis. Details on the morphology of the marginal hooks were not provided in the description of Prudhoe (1957), which are added in the present study. Comparative measurements are presented in Table 5.

Macrogyrodactylus karibae Douëllou et Chishawa, 1995 Figs. 2G–I, 3C,D (iii); Table 6 T y p e h o s t: Clarias gariepinus (Burchell) (Siluriformes: Clariidae). Ty p e l o c a l i t y: Lake Kariba, Zimbabwe. O t h e r r e c o r d s: Clarias gariepinus. South Africa – Khalil and Mashego (1998), Olivier et al. (2009), Matla (2012); Zimbabwe – Douëllou and Chishawa (1995), Barson et al. (2008, 2010). L o c a l i t i e s (p r e s e n t s t u d y): SouthAfrica: KuShokwe Pan and Usuthu River, Ndumo Game Reserve, KwaZulu-Natal Province; Zambia: Barotse floodplain, Zambezi River, Northwestern Province. S i t e o f i n f e c t i o n: Skin and gills. Abbreviations: IC –Iceland, KY – Kenya, M. – Macrogyrodactylus, SN – Senegal, SA – South Africa, ZI – Zimbabwe, ZM – Zambia. Vo u c h e r m a t e r i a l: Four voucher specimens deposited in, NMB P 818–821. R e p r e s e n t a t i v e D N A s e q u e n c e s: 715–741 bp long sequence of the ITS1-5.8S-ITS2 region of the rRNA gene of two isolates. GenBank accession numbers: MZ869845, MZ869851. Hologenophore, NMB P 829. S p e c i m e n s s t u d i e d: n = 8 (KuShokwe Pan, SA), n = 1 (Usuthu River, SA), n = 2 (Barotse floodplain, ZM). I n f e c t i o n r a t e: KuShokwe Pan (SA): P = 20%, IF = 1–2; Usuthu River (SA): P = 66%, IF = 1; Barotse floodplain (ZM) P = 6%, IF = 1. Morphological observations (measurements provided in Table 6): General morphology of the haptoral sclerites is similar to the description of Douëllou and Chishawa (1995). Marginal hook sickle blade slender and inwardly curved point, distal side slightly convex as it joins sickle blade. Base of sickle presents noticeable curvature toward anterior end of sickle, has a convex distal side with an indentation as it joins sickle blade that sharply curve inward, tapering into a sharp point that stops before proximal side of sickle base; proximal side of sickle base curved. Cirrus observed in two specimens from KuShokwe Pan (SA) and Barotse floodplain (ZM), respectively, armed with 15 small spines and one large spine (Fig. 2I). Remarks. Macrogyrodactylus karibae can be easily distinguished from M. congolensis in having a ventral bar with short anterolateral processes and a short central arm. It can also be distinguished from M. clarii in having slender hamuli that is sharply curved into the point and root and in having a single uniform dorsal bar, wider than long (see Figs. 2G–H, 3C). Additionally, M. karibae presents a curved proximal side of sickle base, opposed to the absence of a curved appearance in M. clarii and M. congolensis (Fig. 2H and Fig. 3D (iii)). Dimensions for the hamuli (total length, point, shaft and root length) for specimens in the present study from NGR (SA) and Barotse floodplain (ZM) are within the ranges reported for the same species from other localities in southern Africa (Table 6) (Douëllou and Chishawa 1995, Khalil and Mashego 1998, Barson et al. 2010). The size of the dorsal and ventral bars is within the size ranges previously reported. The marginal hook size and morphology are comparable to previously reported data, specimens from NGR seem to have a slightly larger marginal hook sickle than previously reported. In the description and re-evaluation of M. karibae, Douëllou and Chishawa (1995) and Khalil and Mashego (1998) did not provide details on the morphology of the marginal hooks, which are provided in the present study. Comparative measurements are presented in Table 6.