Australian Army Malaria Institute, Gallipoli Barracks, Enoggera, Queensland, Australia.
Malar J. 2010 Feb 2;9:40. doi: 10.1186/1475-2875-9-40.
The island of Timor lies at the south-eastern edge of Indonesia on the boundary of the Oriental and Australian faunal regions. The country of Timor-Leste, which occupies the eastern part of the island, is malarious, but anopheline faunal surveys and malaria vector incrimination date back to the 1960 s. Over the last decade the malaria vectors of south-east Asia and the south-west Pacific have been intensely studied using molecular techniques that can confirm identification within complexes of isomorphic species. The aim of this study is to accurately identify the Anopheles fauna of Timor-Leste using these techniques.
The survey was carried out over the period February to June 2001. Standard entomological techniques--human landing collections, larval collections and CO2 baited light traps--were used to collect anophelines from the main geographical regions: coastal plains, inland plains, and highlands. Specimens were processed for identification by morphology and genotyped for the ribosomal DNA ITS2 by restriction analysis and/or DNA sequencing. Phylogenetic relationship of Anopheles sundaicus and Anopheles subpictus individuals was also assessed using DNA sequences from the ITS2 and mitochondrial cytochrome-b. All specimens, other than those from larval surveys, were processed to detect the presence of the Plasmodium parasite circumsporozoite protein by ELISA for vector incrimination.
Of 2,030 specimens collected, seven species were identified by morphology: Anopheles barbirostris, Anopheles aconitus, Anopheles annularis, Anopheles maculatus, Anopheles peditaeniatus, An. sundaicus and Anopheles vagus. These were confirmed by molecular analysis with the addition of Anopheles flavirostris and an unidentified species designated here as An. vagus genotype B. This latter species was morphologically similar to An. vagus and An. subpictus and is likely to be the An. subpictus described by other workers for Timor. However, genetically this species showed strong affinities to the An. sundaicus complex. Anopheles vagus was the most common species but was rarely collected coming to bite humans; An. barbirostris and An. vagus genotype B were the two most common species collected in human landing catches and both were found positive for CS protein.
The anopheline fauna of Timor-Leste is of Oriental origin with no evidence of elements from the Australian Region. The existence of species complexes will make the use of morphological markers problematic in the country. Using molecular analysis a number of issues regarding the anopheline fauna of Timor-Leste were resolved and nine putative species of Anopheles were identified; two species: An. barbirostris and An. vagus genotype B, were incriminated as malaria vectors.
帝汶岛位于印度尼西亚东南部，位于东洋和澳洲动物区系的边界上。东帝汶这个国家占据了该岛的东部，是疟疾流行地区，但按蚊动物区系调查和疟疾媒介归咎于 20 世纪 60 年代。在过去的十年中，使用能够在同形种复合体中确认鉴定的分子技术，对东南亚和西南太平洋的疟疾媒介进行了深入研究。本研究的目的是使用这些技术准确识别东帝汶的按蚊动物区系。
调查于 2001 年 2 月至 6 月进行。使用标准的昆虫学技术——人体降落采集、幼虫采集和 CO2 诱饵灯诱集，从主要地理区域收集按蚊：沿海平原、内陆平原和高原。通过形态学和核糖体 DNA ITS2 的限制性分析和/或 DNA 测序进行基因分型，对标本进行鉴定。还使用来自 ITS2 和线粒体细胞色素-b 的 DNA 序列评估了按蚊属苏拉威西亚种和按蚊属斑腿亚种个体的系统发育关系。除幼虫调查外的所有标本均通过 ELISA 检测环孢子蛋白的存在来处理，以进行媒介归咎。
共采集 2030 个标本，通过形态学鉴定出 7 个种：巴比亚按蚊、阿孔按蚊、环纹按蚊、斑腿按蚊、四斑按蚊、苏拉威西按蚊和淡色库蚊。通过分子分析证实了这一点，增加了黄头按蚊和一种在这里被指定为按蚊属苏拉威西亚种 B 的未识别种。后一种在形态上与按蚊属苏拉威西亚种和按蚊属斑腿亚种相似，很可能是其他作者为帝汶描述的按蚊属斑腿亚种。然而，从遗传学角度来看，这种物种与按蚊属苏拉威西复合体有很强的亲缘关系。按蚊属苏拉威西亚种是最常见的物种，但很少来咬人；巴比亚按蚊和按蚊属苏拉威西亚种 B 是人体降落采集最常见的两种，两者都检测到 CS 蛋白阳性。
东帝汶的按蚊动物区系起源于东方，没有来自澳大利亚区系的元素。种复合体的存在将使该国使用形态标记物成为问题。通过分子分析，解决了一些关于东帝汶按蚊动物区系的问题，并鉴定了 9 种可能的按蚊属；两种物种：巴比亚按蚊和按蚊属苏拉威西亚种 B，被归咎为疟疾媒介。
