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In this article, the variability of physical settings of anchialine systems in Indonesia is discussed together with the consequences these settings have for the environment and biota within the systems. Exploration in two karstic areas (Berau, East Kalimantan and Raja Ampat, West Papua) has resulted in the discovery of 20 previously unknown anchialine systems in Indonesia. Based on parameters such as bathymetry, size, coastline, salinity, water temperature, pH, degree of connection to the sea, and the presence-absence of selected key taxa we distinguish three types of (non-cave) anchialine systems in the Indo-Pacific: (1) Marine lakes with large and deep basins containing brackish to almost fully marine waters. Marine lakes show a range in the degree of connection to the sea with the result that the higher the connection the more the lake resembles a lagoon in both water chemistry and biota, while the more isolated lakes have brackish water and contain unique species that are rarely found in the adjacent sea. (2) Anchialine pools with small and shallow basins containing brackish water and low diversity of macrofauna. (3) Blue pools in chasms that contain water with a clear halocline and are possibly connected to anchialine caves. Study of the many unique features of anchialine systems will enhance our understanding of the physical and ecological processes responsible for diversification in tropical shallow marine environments. [ABSTRACT FROM AUTHOR]

Only two alveolinoid genera, Borelis de Montfort, 1808 and Alveolinella H. Douvillé, 1907 thrive in present-day Indo-Pacific coral-reef settings. The former is widespread from the Western (Red Sea) to the Central Indo-Pacific and Caribbean Sea coasts, whereas the latter occurs in the Central and Eastern Indo-Pacific area. A third Indo-Pacific alveolinoid genus, Flosculinella Schubert in Richarz, 1910, is exclusively fossil. New fossil and Recent material and a type collection were analysed to assess the taxonomic status of Flosculinella and Alveolinella species and understand alveolinoid phylogeny in the Indo-Pacific area. The latest Oligocene–middle Miocene Flosculinella globulosa , the early–middle Miocene F. reicheli , F. bontangensis , F. cucumoides , Alveolinella borneensis and the middle Miocene–Recent A. quoyi are herein circumscribed in terms of shell length, diameter of the proloculus, whorl number of the first attic occurrence, and number of supplementary chamberlets in the attic floor per chamberlet in the main floor. The occurrence of the preseptal passage only and Y-shaped septula in Borelis schlumbergeri , Flosculinella and Alveolinella are characters of phylogenetic significance. Oligocene–early Miocene Borelis philippinensis is inferred as the common ancestor of these taxa. The diversification of Flosculinella and Alveolinella occurred in the Coral Triangle of Southeast Asia during the early–middle Miocene. The northernmost occurrence of the Tortonian–Recent A. quoyi , widespread from Central to the Eastern Indo-Pacific areas, is in the Ryukyu Islands. [Display omitted] • Shell structures circumscribe five Flosculinella and Alveolinella species. • The common ancestor of Flosculinella and Alveolinella is Borelis philippinensis. • Speciation occurred in the lower–middle Miocene Coral Triangle of SE Asia. • Recent A. quoyi appeared in the Tortonian of East Kalimantan. • The northernmost occurrence of A. quoyi is in the Ryukyu Islands. [ABSTRACT FROM AUTHOR]

Abstract: Most studies of Cenozoic shallow-water, mixed carbonate–siliciclastic depositional systems have focused on their sedimentology. To date, however, comprehensive analyses of biotas and biofacies of Indo-West Pacific reefs that developed in mixed carbonate–siliciclastic systems are lacking. This study describes the palaeoenvironment and biodiversity of a late Burdigalian patch reef that developed in a mixed carbonate–siliciclastic depositional system. The studied exposure is located at the northeast margin of the Kutai Basin near Bontang (Indonesia), and is approximately 80m wide and 25m thick. Multi-taxon analysis of the most abundant fossil groups, including larger benthic foraminifera, corals, coralline algae, and bryozoans, aims to provide a model for environmental interpretation that will allow comparison with similar deposits of Indo-West Pacific region. Based on fossil content and lithology, five different facies types have been distinguished: foraminiferal packstone (FP), bioclastic packstone with foralgal communities (BP), thin-platy coral sheetstone (CS), platy-tabular coral platestone (CP), and shales (S). Among larger benthic foraminifera, smaller and more robust forms dominate in the FP and BP facies, while larger and flatter forms are the most abundant in the CS and CP facies. Thin-platy corals are dominant in the CS facies and gradually change into thicker platy-tabular forms in the CP facies. Assemblages and growth forms of coralline algae show no major differences between the facies types and are dominated by melobesioids and Sporolithon. The majority of bryozoan species are encrusting and were found only in the CS facies. Light-dependent organisms occurring in the reef indicate low light conditions typical for mesophotic reefs. The relatively small size of this reef complex and quite distinct vertical changes in the facies types, combined with the high siliciclastic content in most of the units, points to strong terrigenous input affecting water transparency as the main factor controlling the reef growth. [Copyright &y& Elsevier]