Description: English: The Opisthostoma concinnum complex consists of 16 populations. All are restricted to small limestone outcrops along the lower Kinabatangan River in Sabah, Malaysian Borneo. The populations have been identified with five- or six-letter codes: BATANG (O. concinnum at Batangan), BODTAI (O. concinnum at Bod Tai), GOMcon (O. concinnum at Gomantong), GOMmir (O. mirabile at Gomantong), KAMPUN (O. concinnum at Batu Kampung), KERUAK (O. concinnum at Keruak), MATERI (O. concinnum at Materis), MAWAS (O. concinnum at Mawas), PANGI (O. concinnum at Pangi), QUARRY (O. concinnum at Quarry), TABAco (O. concinnum at Tandu Batu), TABAsi (O. simplex at Tandu Batu), TOMBEE (O. concinnum at the east side of Tomanggong Besar), TOMBEW (O. fraternum at the west side of Tomangong Besar), TOM-2 (O. concinnum at Tomanggong 2), TOMKEC (O. concinnum at Tomanggong Kecil). All populations are allopatric, except those from Gomantong, Tandu Batu, and Tomanggong Besar. From: Schilthuizen, M. et al., 2006. MICROGEOGRAPHIC EVOLUTION OF SNAIL SHELL SHAPE AND PREDATOR BEHAVIOR. Evolution, 60(9), 2006, pp. 1851–1858. Date: 12 October 2005. Source: Own work. Author:
Schilthuizen.