Dorymyrmex pyramicus albemarlensis Wheeler, 1919

Herrera Léon Baert Wouter Dekoninck, Henri W., Causton, Charlotte E., Sevilla, Christian R., Pozo, Paola & Hendrickx, Frederik, 2020, Distribution and habitat preferences of Galápagos ants (Hymenoptera: Formicidae), Belgian Journal of Entomology 93, pp. 1-60 : 7

Dorymyrmex pyramicus albemarlensis Wheeler, 1919

( ANTWEB: CASENT0173213). ( Map 3 )

This species is possibly endemic ( LUBIN, 1984; F. Cuezzo pers. comm., XI.2009). It is distributed on 14 islands and is associated with natural areas. The first specimens were collected in 1898 on Isabela (WHEELER, 1919). This species builds nests in the soil, on sandy beaches, open areas between vegetation and lava (WHEELER, 1924; LUBIN, 1984), or in sandy patches within lava fields near the coast, surrounded by the occasional grass, trees of B. graveolens and Opuntia cacti .

Dorymyrmex pyramicus albemarlensis apparently prefers dry zones, where it feeds on extrafloral nectaries of the giant endemic cacti Opuntia echios Howell and Jasminocereus thouarsii (F. A.C. Weber) Backeb ( Meier, 1994). The species can be found occasionaly in the Transition zone and rarely in humid areas. It has been collected in stands of Cryptocarpus pyriformis Kunth , under trees of Hippomane mancinella L., in forests of B. graveolens that also include Zanthoxylum fagara ( L.) Sarg, Macraea laricifolia Hook. f. , Cordia sp , Waltheria ovata Cav. , C. scouleri , Darwiniothamnus lancifolius (Hook. f.) Harling , Alternanthera filifolia (Hook. f.) J.T. Howell and grasses. Dorymyrmex pyramicus albemarlensis is also recorded in areas with Scalesia affinis Hook. f. , Castela galapageia Hook. f. , Opuntia insularis Stewart , Cordia leucophlyctis Hook. f. and dry grass. Other records are from vegetation composed of Opuntia helleri K. Schum. , C. scouleri , Cordia lutea Lam. , Lantana peduncularis Andersson and dry litter. In the humid zone of Alcedo volcano (Isabela Island) workers were collected in a closed woodland of P. floribunda . Dorymyrmex pyramicus albemarlensis is preyed upon by Tmarus stolzmanni Keyserling, 1880 , a crab-spider ( Thomisidae ) distributed in the arid and transition zones ( LUBIN, 1983; BAERT, 2008). The invasive ants W. auropunctata and S. geminata could have displaced D. pyramicus albemarlensis on the islands of Santa Cruz and Baltra where it was once common (WHEELER, 1924).

Figures

Map 3. Distribution of Dorymyrmex pyramicus albemarlensis Wheeler, 1919.