Raillietina, Fuhrmann, 1920

Panti-May, Jesús Alonso, Digiani, María Celina, Palomo-Arjona, Eduardo Emir, Gurubel-González, Yessica Margely, Navone, Graciela T., Machain-Williams, Carlos, Hernández-Betancourt, Silvia F. & Robles, María Del Rosario, 2018, A checklist of the helminth parasites of sympatric rodents from two Mayan villages in Yucatán, México, Zootaxa 4403 (3), pp. 495-512 : 498

Raillietina sp.

Site of infection: Small intestine

Host: Sigmodon toltecus

Locality: Xkalakdzonot

Prevalence and mean intensity (range): 26.3% (5/19) and 2.4 (1–6)

Specimens deposited: MLP-He 7422 and CNHE 10714

Comments: The morphological characteristics observed in our specimens agreed with those established for the genus Raillietina (Khalil et al. 1994) , i.e. rostellum with double alternative crowns; armed suckers; craspedote proglotids; single reproductive organs; unilateral genital pores; small cirrus-sac, not reaching or just crossing the osmoregulatory canals; numerous testes; ovary median; two to eight eggs per capsule. Collected specimens had rostellum 105–138 in diameter with 64–68 hooks; hooks 25–28 long; suckers 96–128 in diameter with spines of 6– 8 long; 26– 29 egg capsules in young gravid proglottids; egg capsules 100–108 long by 60–70 wide; and five to eight eggs of 29–33 long by 25–29 wide. In North America, there are two common species of Raillietina in Sigmodon , Raillietina bakeri Chandler and Raillietina sigmodontis Smith. However , the specimens collected from S. toltecus cannot be identified at species level due to the fact that gravid proglottids were not mature. Also, our specimens had similar numbers of egg capsules and eggs per capsule to that of R. sigmodontis (30–35) and R. bakeri (6–9), respectively ( Chandler 1942; Smith 1954).

In México, the genus Raillietina has been reported for several mammals. Among small rodents, Raillietina baeri Meggitt & Subramanian was recorded from Heteromys irroratus Gray in Hidalgo ( Carmona-Huerta 1994), and Raillietina celebensis (Janicki) from Oryzomys sp. in Oaxaca (Flores-Barroeta & Hidalgo-Escalante 1960). Also, unidentified species of Raillietina have been reported from Heteromys pictus Thomas in Durango (García- Prieto et al. 2012), Dipodomys phillipsi Gray in Puebla and Veracruz (García-Prieto et al. 2012), Oryzomys couesi (Alston) and Oryzomys melanotis Thomas in San Luis Potosí (Underwood et al. 1986), H. irroratus in Tlaxcala (García-Prieto et al. 2012), and Chaetodipus sp. in Zacatecas (Martínez-Salazar et al. 2016). This is the first record of a species of Raillietina in Yucatán and from S. toltecus in México.