coustanis.l. Mukiama and Mwangi1989, HMGCS1 Carrara et al.1990, Robert et al.1992, Antonio-Nkondjio et al.2006, Dia et al.2008, Kerah-Hinzoumbe et al.2009). Secondary vectors have been acknowledged for their importance locally in malaria transmission, as they may help to augment or lengthen the malaria transmission period (Mukiama and Mwangi1989, Wanji et al.2003). Further, it has been suggested that since many secondary vectors are exophilic and exophagic, they could potentially sustain malaria transmission after the main endophilic and endophagic vectors have been reduced by interior control measures such as interior residual spraying (S)-(?)-Limonene or insecticide-treated bed net (ITN) use (Gillies1964, Wilkes et al.1996, Antonio-Nkondjio et al.2006). Many of the potential secondary vectors mentioned above are generally thought to be of negligible importance due to their exhibited zoophilic behavior (Gillies and DeMeillon1968). In particular,An. squamosushas been shown not to bite humans in the presence of alternate hosts (Symes1931, Bruce-Chwatt et al.1960, Hamon et al.1964, Jupp et al.1980), and the human blood indices (HBIs) determined forAn. coustanis.l. have been low (Adugna and Petros1996), (S)-(?)-Limonene with the majority of blood meals recognized having been of bovine origin (Antonio-Nkondjio et al.2006, Muriu et al.2008). In contrast to these findings,An. coustanis.l. andAn. squamosusin Macha have exhibited unexpectedly high anthropophily.An. coustanicomplex mosquitoes have been found harboring sporozoites in Katanga in the Democratic Republic of the Congo (Vincke1946) and in Tanzania (Gillies1964). Additionally,An. coustanis.l. has been found positive forPlasmodium malariaein Cameroon by enzyme-linked immunosorbent assay (ELISA) for the circumsporozoite protein (CSP) (Antonio-Nkondjio et al.2006). Dissections ofAn. squamosushave found sporozoite-positive specimens in Tanzania (Gillies1964) and Zimbabwe (Gillies and DeMeillon1968). Because of this apparent capacity to transmitPlasmodium, the high degree of anthropophily ofAn. coustanis.l. andAn. squamosusdescribed here increases their importance as potential secondary vectors. == Materials and Methods == == Mosquito collection and handling == Mosquitoes were collected for this study from three village areas, Chidakwa, Lupata, and Namwalinda, in the Southern Province of Zambia. Each village area is situated within 10 km of the Johns Hopkins Malaria Research Institute’s field station in Macha, Zambia (16.39292S, 26.79061E) at an elevation of 1100 m. Selections were performed December through May during the 20072008 and 20082009 rainy seasons. Mosquito foraging behavior, that is, the combination of host-seeking and blood feeding activity, was examined by paired interior/outdoor human landing catch (HLC) and cattle-baited trap (CBT) collections, as well as corresponding Centers for Disease Control (CDC) light trap collections. Indoor/outdoor HLC and CBT selections were performed simultaneously on given nights at three different households, and corresponding CDC trap selections were performed on the following nights in the same sleeping houses as the HLCs. (S)-(?)-Limonene All selections were conducted for a total of 212 trap nights over the two seasons. Teams of two trained field staff performed HLC selections from 20:00 to 06:00 during (S)-(?)-Limonene the 20072008 season and from 19:00 (S)-(?)-Limonene to 07:00 during the 20082009 season. Hourly selections were kept in separately labeled paper cups. CBT and CDC trap selections were performed for the same lengths of time as the HLCs. CBTs, kraals each big enough to encircle one calf, were constructed at each of seven collection households. The kraals were made of felled trees and branches in the style of the larger cattle kraals frequently constructed in the region. Once a calf was led into a kraal, a double-bed-sized untreated bed net was hung above the kraal so that the net rested on the outside of the enclosure, ending about 30 cm above the ground. The top of the net was loosely tied into a funnel. In the morning the upper portion of the net made up of most of the resting mosquitoes was cinched closed, the calf was removed, and any remaining mosquitoes were collected by manual aspiration (Fornadel et al.in press). CDC.