Dolichoplana carvalhoi Corrêa, 1947

Figs. 17–19, 21–23, 26.

External diagnosis (Corrêa 1947). Very similar to Dolichoplana striata in size (up to 20 cm in length) and color pattern (olive-brown background and longitudinal stripes). Specimens can have six stripes, being identical to Dolichoplana striata, or only five stripes, with a single median stripe more conspicuously marked than the paired median stripes of specimens with six stripes. Specimens with five dorsal stripes have a pale venter with three brownish or grayish stripes, a fine median stripe and a broader lateral stripe on each side.

The absence of a head plate differentiates it from both species of Bipalium. The paired eyes differ from the multi eyed species of Caenoplanini as well as Geoplana multipunctata. The large size and the number of stripes differ it from Rhynchodemus sylvaticus and Diporodemus yucatani.

Remarks. Dolichoplana carvalhoi was originally described based on specimens that are externally identical to Dolichoplana striata, but whose copulatory apparatus presented some small variation (Corrêa 1947). Specimens with only five stripes were found later, and a karyotype analysis revealed that six-striped specimens are triploid (3n) while five-striped specimens are diploid (2n) (Álvarez & Almeida 2007). Dolichoplana carvalhoi is likely a junior synonym of Dolichoplana striata and, although this has already been suggested (Froehlich 1967), the synonymization was never formally presented.Since the six-stripe pattern is identical in both species of Dolichoplana, these specimens are often identified as Dolichoplana striata, while five-striped specimens are determined as Dolichoplana carvalhoi solely because this pattern was never formally recorded in Dolichoplana striata. Here we use the name Dolichoplana striata for the six-striped specimens and Dolichoplana carvalhoi for the five-striped specimens. However, we believe that these two names indeed represent a single species.

iNaturalist Records. MEXICO: JALISCO: One specimen observed 1 September 2020; 20.6723°N, - 103.4165°W; 1632m a.s.l.; uploaded by terecast (#58249809).