Otocinclus mimulus Axenrot & Kullander, 2003

A, Pablo Lehmann, Mayer, Fernanda & Reis, Roberto E., 2010, Re-validation of Otocinclus arnoldi Regan and reappraisal of Otocinclus phylogeny (Siluriformes: Loricariidae), Neotropical Ichthyology 8 (1), pp. 57-68 : 60-61

Otocinclus mimulus Axenrot & Kullander, 2003 Fig. 4

Otocinclus mimulus Axenrot & Kullander, 2003: 251 . Type locality: Paraguay: Departamento Caaguazú: río Paraná drainage, small stream (arroyo) at Estancia María Belén, 8 km from Colonel Patricio Colman ; 25°40’13”S 55°5’52”W. Holotype: MNHNP uncatalogued (ex NRM 43480), 34.1 mm SL [Holotype originally cited as MNHNP uncat.].

Diagnosis. Otocinclus mimulus is distinguished from all other Otocinclus species except O. arnoldi , by having five branched rays in the pectoral-fin (vs. six branched pectoral-fin rays), and except from O. arnoldi and O. xakriaba by having the prootic involved in the contact with the hyomandibular articular condyle (vs. only compound pterotic contacting the hyomandibular articular condyle). It is distinguished from O. arnoldi by having an elevated patch of enlarged odontodes on the postero-dorsal parieto-supraoccipital tip and typically having 16-17 caudal vertebrae (see Table 2; vs. having a not elevated patch of enlarged odontodes on the parietosupraoccipital and having 15 caudal vertebrae). It is further distinguished (except for O. affinis , O. hasemani , O. xakriaba , O. arnoldi , and O. flexilis ) by possessing an iris operculum, and (except for O. affinis and O. xakriaba ) by having an elevated patch of enlarged odontodes on the postero-dorsal parietosupraoccipital tip. It is also distinguished from all remaining Otocinclus species (except for O. xakriaba , O. arnoldi , and O. flexilis ) by having a lateral trunk coloration composed of either a row of 3-6 distinct dark blotches or a distinct dark stripe extending from the compound pterotic to the base of the caudal fin, or a diffuse mixture of those two color patterns ( Fig. 4).

Distribution. Otocinclus mimulus is only known from the río Mondai in Paraguay, a left-bank tributary of the lower rio Paraná ( Fig. 5).