Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
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Image catalog (click here). Includes images of holotype.
Range
Costa Rica.
Identification
The two closely related species monteverdensis and sumichrasti are uniquely characterized by the combination of yellow coloration, relatively long, upturned propodeal spines, and long flexuous posterolateral mesonotal setae that are subequal in length to humeral setae. The only difference is that Crematogaster sumichrasti has one or two extremely long setae on the tibiae.
Description of worker
Differing from sumichrasti in the following respects: tibiae with abundant suberect setae, but more uniform in length and none longer than maximum width of tibia (sumichrasti has one or more long macrosetae, subequal in length to twice maximum tibia width); pronotal dorsum with stronger longitudinal carinulae; dorsal and posterior faces of mesonotum meeting at an angle but angle less strongly produced, not tuberculate; dorsal pilosity generally shorter.
Measurements:
Holotype: HL 0.702, HW 0.739, HC 0.685, SL 0.584, EL 0.192, WL 0.777, SPL 0.145, PTH 0.178, PTL 0.239, PTW 0.210, PPL 0.183, PPW 0.228, CI 105, OI 27, SI 83, PTHI 74, PTWI 88, PPI 125, SPI 19.
Other specimens: HL 0.726, 0.639, 0.718; HW 0.799, 0.686, 0.772; HC 0.732, 0.636, 0.699; SL 0.605, 0.554, 0.601; EL 0.199, 0.182, 0.208; A11L 0.248; A11W 0.135; A10L 0.114; A10W 0.119; A09L 0.076; A09W 0.093; A08L 0.057; A08W 0.074; WL 0.840, 0.719, 0.832; SPL 0.145, 0.134, 0.156; PTH 0.195, 0.184, 0.181; PTL 0.249, 0.222, 0.228; PTW 0.220, 0.206, 0.224; PPL 0.180, 0.151, 0.176; PPW 0.246, 0.220, 0.235; CI 110, 107, 108; OI 27, 28, 29; SI 83, 87, 84; PTHI 78, 83, 79; PTWI 88, 93, 98; PPI 137, 146, 134; SPI 17, 19, 19; ACI 0.24.
Description of Queen
A normal queen (dorsal face of propodeum drops steeply from postscutellum and much of propodeum appears ventral to scutellum and postscutellum) with general shape, sculpture, and pilosity characters of the worker.
Natural History
Crematogaster monteverdensis inhabits moist forest areas in the Monteverde community area in the Cordillera de Tilar‡n and at a similar elevation on Cerro Cacao in the Cordillera de Guanacaste. I first encountered the species in Monteverde, where I observed workers and the small, dealate queens foraging together on the outside walls of a house. Subsequent collections were from nests in dead branches, either in recent treefalls or on the ground. These collections were generally located at pasture/forest edges. Nests were polygynous, with multiple dealate queens. Workers could be recruited to baits of mixed honey and solid vegetable oil. I have never seen alate queens, and one nest collection contained small apterous males similar to Wheeler's description of the males of atitlanica (Wheeler 1936, see sumichrasti).
Comments
I identified monteverdensis specimens first as sumichrasti until I discovered the consistent differences in tibial pilosity and promesonotal profile. Crematogaster sumichrasti seems to have a microparapatric distribution with monteverdensis, because typical sumichrasti occur just downslope from Monteverde, at 700m elevation on the road down to the PanAmerican Highway.
Page author:
John T. Longino, The Evergreen State College, Olympia WA 98505 USA. longinoj@evergreen.edu
Date of this version: 4 March 2003.
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