The ants of the genus Rhopalothrix Mayr, 1870 (Hymenoptera, Formicidae, Myrmicinae) in Colombia Author Guerrero, Roberto J. https://orcid.org/0000-0003-3244-2754 Universidad del Magdalena, Facultad de Ciencias Basicas, Programa de Biologia, Santa Marta, Magdalena, Colombia rguerrero@unimagdalena.edu.co Author Grajales-Andica, Andres F. https://orcid.org/0000-0001-9166-0562 Departamento de Ecologia y Recursos Naturales, Centro Universitario de la Costa Sur, Universidad de Guadalajara, Autlan de Navarro, Mexico Author Fernandez, Fernando https://orcid.org/0000-0002-6862-3592 Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogota, D. C., Colombia Author Tocora, Maria C. https://orcid.org/0000-0002-5304-4010 Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON M 5 S 3 B 2, Canada Author Fiorentino, Gianpiero https://orcid.org/0000-0001-6948-5032 New Jersey Institute of Technology, New Jersey, USA Author Garcia, Delly R. https://orcid.org/0000-0002-4821-6754 Universidad del Quindio, Armenia, Quindio, Colombia text ZooKeys 2024 2024-02-13 1191 129 150 http://dx.doi.org/10.3897/zookeys.1191.110418 journal article http://dx.doi.org/10.3897/zookeys.1191.110418 1313-2970-1191-129 CA34EBDA15B543CD99666CF8B322EE7D F10DAA0E857B5B449B284B4E842A4AAB Rhopalothrix isthmica (Weber, 1941) Figs 2 , 6 Worker measurements ( N = 8). MdL 0.28-0.3, MdbW 0.08-0.09, ClyL 0.14-0.19, ClyW 0.4-0.43, HL 0.51-0.53, HW 0.54-0.59, WL 0.51-0.56, PrnW 0.29-0.32, PetL 0.23-0.3, PpetL 0.12-0.15, PetW 0.16-0.17, PpetW 0.28-0.31, T4L 0.49-0.55, GL 0.55-0.58. Geographic range. Colombia, Honduras, Guatemala, Panama. In Colombia, this species is known from Antioquia, Bolivar , Santander and Sucre. Examined material. Colombia • 1 worker ; Antioquia , Amalfi , canon del Porce , La Cancana ; 6.76667°N , 74.91667°W ; 1000 m a.s.l. ; 30 Jul. 1997 ; F. Serna leg.; ex sifted leaf litter mini-Winkler, low vegetation (stubble); MEFLG 11112. • 1 worker ; Bolivar , SFF Los Colorados, La Yaya ; 9.92611°N , 75.10583°W ; 280 m a.s.l. ; 3-5 Jul. 2001 ; ex sifted leaf litter, dry forest; IAvH-E-263435. • 3 workers ; La Guajira , Dibulla, Bello Horizonte, rio Canas ; 11.25687°N , 73.44852°W ; 6 m a.s.l. ; 12 Oct. 2015 ; ex sifted leaf litter, dry forest; IAvH-E-172164. • 3 workers ; La Guajira , Dibulla, Alto San Jorge, rio Canas ; 11.218°N , 73.428°W ; 73 m a.s.l; 12 Oct. 2015 ; ex sifted leaf litter, dry forest; IAvH-E-172162, IAvH-E-172163, IAvH-E-172165. • 1 worker ; Santander , Rionegro, Vereda Galapagos, Km 32 via al mar, C.I. La Zuiza ; 7.370278°N , 73.17762°W , 537 m a.s.l. ; 2020; J.M. Montes leg.; CTNI 8304. • 2 workers ; Santander , Puerto Wilches, Platero; 7.3483°N , 73.8960°W ; 28 m a.s.l. ; 10-15 Nov. 2021 ; ex sifted leaf litter Winkler No. 4; L. Perez leg.; CBUMAG:ENT:35949. • 1 worker ; Santander : Puerto Wilches, Vereda Puente Sogamoso; 7.30537°N , 73.82779°W ; 87 m a.s.l. ; 22 Jul. 2022 ; L. Velazquez leg.; IAvH-E-226990. • 14 workers ; Santander , Puerto Wilches , Vereda Centro , 7.32972°N , 73.84256°W ; 88 m a.s.l. ; 8 Jul. 2022 ; L . Arcila leg; ex sifted leaf litter, riparian forest; IAvH-E-226992, IAvH-E-226993, IAvH-E-226994, IAvH-E-226995, IAvH-E-226996, IAvH-E-232292, IAvH-E-233744, IAvH-E-238973, IAvH-E-238974, IAvH-E-238975, IAvH-E-238976, IAvH-E-243661, IAvH-E-243688. • 1 worker ; Santander : Puerto Wilches , Vereda San Claver ; 7.34831°N , 73.76817°W ; 93 m a.s.l. ; 8 Jul. 2022 ; C. Quevedo-Vega leg.; ex sifted leaf litter, riparian forest; IAvH-E-226997. • 1 worker ; Santander : Puerto Wilches , Vereda San Claver ; 7.34792°N , 73.76817°W ; 77 m a.sl.; 8 Jul. 2022 ; C. Quevedo-Vega leg.; ex sifted leaf litter, riparian forest; IAvH-E-226998 . Natural history. Rhopalothrix isthmica workers inhabit dry forest in northern Colombia and both in open grassland and riparian forest in eastern Colombia. In the latter it is a relatively abundant species, being found in 8 of 20 MiniWinkler litter samples. Rhopalothrix isthmica populations have an elevational distribution from near sea level to 1000 m. Comments. The morphology of the workers matches the diagnostic characters of R. isthmica , including HW 0.57-0.61 ( N = 6) recorded by Longino and Boudinot (2013) . In the workers of populations from La Guajira (northern Colombia), the portion of the lamella ventral to the propodeal tooth (infradental lamella) is relatively straighter on the outer margin than described by Longino and Boudinot (2013) . Figure 6. Rhopalothrix isthmica worker (IAvH-E-172166) A full-face view B lateral view C mandible distinguishing the teeth of the apical fork; drawing inserted showing the arrangement of the teeth of the apical fork of the mandible D dorsal view. Scale bars: 0.3 mm.