Viannaia sp.

Panti-May, Jesús Alonso, Chan-Casanova, Anyela Jackelin, Canche-Pool, Elsy, Tello-Martín, Raúl, Ruiz-Piña, Hugo, Concha-Guillermo, Henry, Guiascón, Oscar Retana-, Vega, Pedro Pablo Martínez, Chablé-Santos, Juan, Martínez, Erendira Estrella-, Moguel-Chin, Wilson Isaias, Hernández-Orts, Jesús S., Hernández-Mena, David I., Mendoza-Garfias, Berenit & García-Prieto, Luis, 2024, Morphological and molecular data on helminths of Didelphis virginiana and Philander vossi (Mammalia: Didelphidae) from the Yucatán Peninsula, southeast Mexico, Zootaxa 5463 (1), pp. 1-24 : 9

Viannaia sp.

Site of infection: Small intestine.

Host species: Didelphis virginiana and Philander vossi .

Localities: Campeche (Campeche) and Chetumal (Quintana Roo).

Prevalence: Didelphis virginiana 16.7% (1/6), Philander vossi 100% (1/1).

Intensities: Didelphis virginiana 73, Philander vossi 22.

Specimens deposited: CNHE 12878, 12879.

GenBank accession number: PP662461.

Comments: The nematodes were identified as belonging to the genus Viannaia based on the characteristics of synlophe and the bursa. Male 4,260 ‒4,840 in body length. Bursa subsymmetrical, heart-shaped, with 2-1-2 pattern. Rays 8 long, reaching the margin of the bursa ( Figure 4B ). Rays 10 simple. Spicules short, subequal, 130‒145 long, representing 3‒3.1% of the body length. Monodelphic female 4,650 ‒5,570 in body length. Eggs ovoid, 60‒65 long by 30‒40 wide. The genus Viannaia comprises 19 species: Viannaia conspicua Travassos , Viannaia didelphis Travassos , Viannaia hamata Travassos , Viannaia pusilla Travassos , Viannaia viannai Travassos , Viannaia skrjabini Lent & Freitas , Viannaia philanderi Wolfgang , Viannaia monodelphisi Durette-Desset , Viannaia metachirops Durette-Desset , Viannaia bisbali Guerrero, Viannaia reigi Guerrero, Viannaia tenorai Guerrero, Viannaia minispicula Guerrero, Viannaia guayanensis Guerrero, Viannaia venezuelensis Guerrero, Viannaia gabaldoni Guerrero, Viannaia barusi Guerrero, V. arriaguensis , and Viannaia angelae Ramírez-Cañas, López-Caballero & Mata-López. Viannaia hamata is morphological closest to the species found in the Yucatán Peninsula, with which it shares the length of the spicules and the esophagus ( Guerrero 1985; Lopes de Jesus 2020). However, V. hamata differs from the studied specimens in having a smaller body length (880‒2,300 vs. 4, 260‒5570), a shorter rays 4 and rays 10 forked ( Guerrero 1985; Vicente et al. 1997). Based on these findings, the nematodes collected in the Yucatán Peninsula likely represent an undescribed Viannaia species.

In addition to V. arriaguensis , three species of Viannaia have been reported in Mexico: V. didelphis from D. virginiana in Colima ( Monet-Mendoza et al. 2005) and Morelos ( Ortíz-Villaseñor 2000), V. viannaia from D. virginiana and D. marsupialis in Campeche, Chiapas, Colima, Oaxaca, Puebla, Tabasco, Veracruz ( Acosta-Virgen et al. 2015), and Guerrero ( Monet-Mendoza et al. 2005), and V. angelae from D. virginiana in Colima ( Ramírez-Cañas et al. 2021). Further, unidentified species of Viannaia have also been reported in Chiapas ( Acosta-Virgen et al. 2015), Colima ( García-Valle et al. 2023), Guerrero ( Monet-Mendoza et al. 2005), and Veracruz ( Cañeda Guzman 1997; Monet-Mendoza et al. 2005). This is the first of Viannaia in Campeche and Quintana Roo.

Figures

FIGURE 4. A. Male caudal bursa of Viannaia arriguensis from Philander vossi, ventral view. B. Male caudal bursa of Viannaia sp. from Didelphis virginiana, ventral view. C. Cross section at midbody showing features of the synlophe of male Travassostrongylus sp. from Didelphis virginiana. D. Male caudal bursa of Travassostrongylus sp. from Didelphis virginiana, ventral view. E. Anterior end of female Strongyloides sp. from Philander vossi, ventral view. F. Female tail of Strongyloides sp. from Philander vossi showing the anus, lateral view. G. Vulva of Strongyloides sp. from Philander vossi, lateral view. Abbreviations: anus (a), egg (e), intestine (i), spicule (s), vulva (v), dorsal ray (dr), esophagus (es).