Protistolophus, Short, 2010

Vorst, Oscar, 2024, A second species of Protistolophus Short from Peru (Coleoptera: Hydrophilidae: Hydrophilinae), Zootaxa 5537 (3), pp. 445-450 : 449

Redefinition of Protistolophus

The discovery of a second species of Protistolophus obviously extends the original definition of the genus, as it was based on a single species, P. spangleri . Since the new species is quite close to the genotype, I refrain from a full, extensive redescription. However, some more important deviations from the characters proposed in the original generic description are worth noting. The absence of an apical emargination of the fifth visible ventrite while present in P. spangleri is the most noteworthy, as the absence in the remaining Hydrophilini thus no longer can be considered a homoplasious synapomorphy separating them from Protistolophus ( Short 2010) . The dorsal punctation is in general less extensive. On the labrum the transverse row of punctures is incomplete, broadly interrupted, not complete as in P. spangleri ; the pronotum with both anterior and posterior arcs only with a few (<10) punctures, not continuous; elytra with the four inner striae with only very few (ca. 10) punctures, not as irregular rows. Elytra with sutural striae in the posterior half, not the posterior nine-tenths as in P. spangleri .