Review of the Current State of Knowledge on Liometopum apiculatum Mayr, 1870 (Hymenoptera: Formicidae)

The velvet tree ant, or Liometopum apiculatum, is one of the seven species within its genus and among the three with the widest distribution across North and Central America. In 1870, Mayr described it based on worker ants; later, all castes were characterized. This species is distinguished by a pointed petiole and dense pubescence on the gaster. It inhabits diverse vegetation types, including oak and pinyon pine forests, as well as desert scrub, at altitudes ranging from 30 to 2,900 meters above sea level. L. apiculatum forms colonies in various substrates, such as rocks, dead tree trunks, and plant bases, exhibiting both monodomous and polydomous nesting structures. Colony sizes range from a few hundred to hundreds of thousands of workers. The species is omnivorous, playing a ecological role in seed dispersal and nutrient cycling. In the central region of Mexico, the larvae of the reproductive caste (escamoles) are considered a delicacy. Due to their high market value, excessive harvesting has led to overexploitation and population declines in some areas. Consequently, recent studies have primarily focused on its nutritional properties, use, and consumption. However, knowledge gaps persist regarding their distribution, ecology, interspecific interactions, intraspecific variation (morphological and genetic), nesting methods, colony establishment, and foraging strategies. This study updates and integrates available information to advance current understanding of L. apiculatum biology, given that the most recent compilation of its biology, ecology, and behavior is eleven years old. Likewise, this research provides valuable information to support and guide future conservation efforts for this species.