Balucopsylla Rao, 1972

Mu, Fanghong & Huys, Rony, 2021, A new species of Helmutkunzia Wells & Rao, 1976 from an intertidal sandy beach in Xiamen, China and proposal of Pseudobalucopsylla gen. nov. (Copepoda Harpacticoida, Miraciidae), Zootaxa 5051 (1), pp. 487-505 : 497

Notes on Balucopsylla Rao, 1972

Rao (1972) proposed the genus Balucopsylla for its type and only species, B. similis Rao, 1972 , from a sandy beach in Visakhapatnam (formerly known as Waltair) in Andhra Pradesh, India. Rao suggested that his new taxon was most closely related to a group of other genera that exhibit reduced leg armature, including Schizopera , Goffinella Wilson, 1932 , Psammotopa and Protopsammotopa . Justification for its distinct generic status was primarily based on the 3-segmented condition of the P1 endopod in conjunction with the absence of sexual dimorphism on the P2 endopod; this combination is not displayed by any of the genera mentioned above (P1 endopod 2-segmented in Goffinella , Psammotopa , Protopsammotopa ; P2 endopod ♂ modified in Schizopera and Protopsammotopa ). Wells & Rao (1976) further expanded this genus group by including Actopsyllus , Schizoperoides and their newly proposed genus Eoschizopera , stating that in this lineage the shared reduced leg setation, with at most two outer spines on P2–P4 exp-3, appears to be congruent with the similarity in female genital field morphology. They recognized an evolutionary series Eoschizopera – Helmutkunzia – Balucopsylla in which the latter represented the most morphologically reduced taxon. The next record of the genus is the one by Wells (1978) who reported Balucopsylla sp. from the intertidal zone of Moce island, Fiji but this species remained undescribed. Wells & Rao (1987) subsequently added a second species, B. triarticulata Wells & Rao, 1987 , from the Andaman and Nicobar island chain, which appeared more primitive than the type species in the segmentation of the antennary exopod, yet displayed a more reduced armature on the endopods of P2 and P3. Despite these differences Wells & Rao (1987) considered both species congeneric based on their shared absence of sexual dimorphism in the P2 endopod. Their claim that the 3-segmented antennary exopod in B. triarticulata reinforces their previously suggested close relationship between Helmutkunzia and Balucopsylla ( Wells & Rao 1976) is futile since it is based on a plesiomorphic character state. Morphological comparison of the type species, B. similis , with B. triarticulata and related forms subsequently reported by Mielke (1994, 1997), reveals significant differences warranting a subdivision of the genus Balucopsylla . The generic concept of the latter is here restricted to accommodate B. similis as the type and only species while the remaining members are assigned to Pseudobalucopsylla gen. nov. (see below)