Paedocypris progenetica Kottelat, Britz, Tan & Witte, 2006
photo by Aquaristikhaus

Family:  Paedocyprididae (Tiny carps)
Max. size:  0.96 cm SL (male/unsexed); 1.03 cm SL (female)
Environment:  benthopelagic; freshwater
Distribution:  Southeast Asia: Indonesia.
Diagnosis:  Paedocypris progenetica is distinguished from Paedocypris micromegethes by: a smaller maximum size (male 9.8mm, versus 11.6; female 10.3mm, versus 11.4), keratinized pad in front of male pelvic fins as a projecting knob (versus flat to slightly swollen), breeding tubercles on the dentary arranged in a straight row, without forming a cluster (versus forming a cluster of up to five closely set individual tubercles, subdistally on the lateral side of the dentary, supported by a conspicuous lateral bony extension), pelvic fins of female vestigial, or often missing (versus smaller than in male but similarly shaped), presence of pre-anal-fin-fold in female (a character unique among teleosts; versus absent in both sexes), dense small chromatophores in deep layer on abdomen appearing as a continuous patch, tiny black vermiculations on belly from throat to anus, including on male's pre-pelvic keratinized knob (versus large superficial, isolated chromatophores on belly from throat to anus, absent on male's keratinized pad), numerous small, contiguous chromatophores on middorsal line, organized in 3-5 rows, forming a broad stripe (versus few large isolated chromatophores, forming 1-3 irregular rows), pelvic-fin rays plain brown (versus with rows of spots) (Ref. 56152).
Biology:  One of the smallest fish and vertebrate known, with the smallest mature female measuring a mere 7.9 mm (Ref. 56152).
IUCN Red List Status: Near Threatened (NT); Date assessed: 28 January 2019 (B2ab(i,ii,iii)) Ref. (126983)
Threat to humans:  harmless

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