Faustula brevichrus ( Srivastava, 1935 ) Yamaguti, 1958

Dronen, Norman O., Blend, Charles K., Mohammed, Essa T. & Bannai, Majid, 2021, Reconsideration of the species assigned to Faustula Poche, 1926 (Digenea: Microphalloidea) with the proposal of five new genera in the Faustulidae Poche, 1926, Zootaxa 5027 (2), pp. 231-253 : 239

Faustula brevichrus ( Srivastava, 1935) Yamaguti, 1958

(Syns. Orientophorus brevichrus Srivastava, 1935 ; Faustula chauhani Gupta & Srivastava, 1960 )

( Fig. 3 )

Type host: Hilsa shad, Tenualosa ilisha (Hamilton) (Clupeidae) .

Type locality: India (freshwater) .

Remarks: Faustula brevichrus differs from all other species in the genus by having a bifurcal genital pore. It further differs from F. keksooni by having a narrower pharynx (90–110; 6–7% of body length vs 132; 5%) and a shorter esophagus (120–200; 9–12%). Faustula brevichrus is somewhat similar to F. gangetica by having a cirrus sac that surpasses the ventral sucker posteriorly, but F. brevichrus has a subterminal oral sucker; much shorter vitelline fields; a narrower pharynx (90–110; 6–7%); a generally smaller oral sucker/pharynx width ratio (maximum of 1:1.8 vs 1:2.2); narrower testes (120 vs 160); a longer postovarian space (455; 34%) and shorter eggs (maximum length 20 vs 25). It is noteworthy that the specimen of F. brevichrus shown in fig.1 of Strivastava (1935) (dorsal view) appears to have been overly compressed during fixation, which may have altered the position of some structures to some extent (i.e., the ventral sucker is shifted to the left while the cirrus sac is shifted to the right). We consider the position of the genital pore and the position of the cirrus sac to be representative of this species and sufficiently different to retain F. brevichrus in Faustula .

Figures

FIGURES 3–4. Diagrammatic illustrations of faustulids (ventral views): 3. Faustula brevichrus (Srivastava, 1935) Yamaguti, 1958 based on Srivastava (1935). 4. Fastula clupeae (Srivastava, 1935) Yamaguti, 1958 based on Srivastava (1935).