Dorymyrmex pyramicus albemarlensis Wheeler, 1919

Dorymyrmex pyramicus albemarlensis Wheeler, 1919 View in CoL

( ANTWEB: CASENT0173213). ( Map 3 View 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).