Insular and Continental, Amber and Living Diptera: Implications for Historical Biogeography and the Caribbean Region

墨西哥南部和伊斯帕尼奥拉岛的渐新世-中新世琥珀沉积物丰富，发现了保存精美的生物包裹体，其中绝大多数为节肢动物，尤其是双翅目。琥珀标本提供了一个无与伦比的机会来解决加勒比动物群的关系和起源问题，但缺乏关于加勒比地区大多数现存双翅目分布的关键信息，以及琥珀化石分类群与现存物种的系统发育关系。本研究建议检查琥珀收藏中AMNH和NMNH所代表的选定群体：Asteia (asteidae), Aulacigaster (aulacigastae), Beckeriella (Ephydridae), Beebeomyia (richardidiae), Carnus/Meoneura (carnides)， Lygistorrhina和Proceroplatus (Mycetophilidae)， Diathoneura和选定的果蝇类群（drosophidae）， Odinia (Odiniidae)，以及phoolomyia （milichida）中的一个物种群。每一种的分类修订将基于物种水平的处理，使用成虫形态学和分支学方法来检查系统发育关系。研究将依靠固定的博物馆标本，但需要在低地热带森林中使用几种一般和特定的收集技术进行广泛的采样，建议在古巴的Hispa ola和哥斯达黎加进行。一名合作者将对选定的琥珀标本进行气相色谱/质谱分析，以更准确地确定其地质来源。研究目的如下：确定上述类群在热带地区的种类及其分布；分布的重复、一致模式的检验；并将化石置于现存物种的系统发育系统中。这些结果的含义是，可以检查分布是否与岛屿起源（替代性）相对应，并且进化枝的最低化石年龄可能为特定的地质解释提供许可的证据或反驳。此外，可以评估地理灭绝在改变分布方面的作用，这直接适用于方差方法。

The abundant deposits of Oligo-miocene amber from southern Mexico and Hispaniola have yielded a great diversity of exquisitely preserved biological inclusions, the large majority being arthropods and especially Diptera. The amber specimens afford an unparalleled opportunity to address questions on the relationships and origins of the Caribbean fauna, but critical information is lacking on the distributions of most extant Diptera in the caribbean, and the phylogenetic relationships of the amber fossil taxa to living species. This research proposes to examine selected groups represented in the amber collections the AMNH and the NMNH: Asteia (Asteiidae), Aulacigaster (Aulacigastridae), Beckeriella (Ephydridae), Beebeomyia (Richardiidae), Carnus/Meoneura (Carnidae), Lygistorrhina and Proceroplatus (Mycetophilidae), Diathoneura and selected Drosophila groups (Drosophilidae), Odinia (Odiniidae), and a species group within Pholeomyia (Milichiidae). Taxonomic revisions of each will be based on species-level treatments using adult morphology and cladistic methodology to examine phylogenetic relationships. Study will resort to pinned museum specimens but requires extensive sampling using several general and specific collecting techniques in lowland tropical forests, which is proposed for Hispa ola, Cuba, and Costa Rica. Gas chromatography/mass spectroscopy will be done by a collaborator on selected amber specimens to more accurately determine their geological provenance. Aims of the research are the following: define species and their distributions for the above groups in the Netropics; test for repeated, congruent patterns of distributions; and place the fossils among the phylogenetic system of extant species. Implications of these results are that distributions can be examined for correspondence to island origins (vicariance), and the minimum, fossil age of a clade may provide permissive evidence for or refute a particular geological explanation. Also, the role of geographical extinctions in modifying distributions can be assessed, which is directly applicable to vicariance methodology.