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Colombia es un país con alta diversidad de hormigas, sin embargo, nuevos taxones se siguen registrando para el país. Cuarenta y siete nuevos registros se relacionan aquí, todos dentro de la subfamilia Myrmicinae: Uno para los géneros Adelomyrmex, Allomerus, Kempfidris, Megalomyrmex, Octostruma y Tranopelta; dos para Rogeria; cinco para Myrmicocrypta; seis para Procryptocerus; siete para Cephalotes; diez para Pheidole y once para Strumigenys. Tres de esos nuevos registros corresponden a especies invasoras, Pheidole indica, Strumigenys emmae y Strumigenys membranifera. Tres especies se citan por primera vez para América del Sur: Pheidole sicaria, Procryptocerus tortuguero y Strumigenys manis. El género Kempfidris se registra por primera vez para Colombia. Se ofrecen comentarios para todas las especies. La diversidad de hormigas en Colombia comprende 104 géneros y casi 1.100 especies. 

Sex-related differences in mortality are widespread in the animal kingdom. Although studies have shown that sex determination systems might drive lifespan evolution, sex chromosome influence on aging rates have not been investigated so far, likely due to an apparent lack of demographic data from clades including both XY (with heterogametic males) and ZW (heterogametic females) systems. Taking advantage of a unique collection of capture–recapture datasets in amphibians, a vertebrate group where XY and ZW systems have repeatedly evolved over the past 200 million years, we examined whether sex heterogamy can predict sex differences in aging rates and lifespans. We showed that the strength and direction of sex differences in aging rates (and not lifespan) differ between XY and ZW systems. Sex-specific variation in aging rates was moderate within each system, but aging rates tended to be consistently higher in the heterogametic sex. This led to small but detectable effects of sex chromosome system on sex differences in aging rates in our models. Although preliminary, our results suggest that exposed recessive deleterious mutations on the X/Z chromosome (the “unguarded X/Z effect”) or repeat-rich Y/W chromosome (the “toxic Y/W effect”) could accelerate aging in the heterogametic sex in some vertebrate clades.