In Appendix 1 a very few locations are mentioned with single records of marker taxa outside their biogeographic provinces. After checking many other such unsubstantiated and un-illustrated records in archives and oil company samples and finding them to be misidentified, such a few single reports are not considered a concern and in most cases cannot be checked. However, there are some areas with more substantial problems,which can be re-investigated. The following are some notes should these anomalies prove worthy of investigation.
van Bemmelen (1949) mentioned some samples with ? Pellatispira and Assilina in the Unit D of Hopper (1941) as being from the eastern arm of Sulawesi. There is ambiguity whether this fauna is from eastern east Sulawesi, near where Koolhoven (1930) recorded Lacazinella cf wichmani. (see p.153 of vB) or in the northwest of this arm, near Bungku - Bongka. Some locations of eastern Sulawesi Eocene strata are shown in the map figure 162 on plate 14 of van Bemmelen (1949), but it is not clear which locations have yielded which fossils. In light of the apparently mixed faunas in parts of PNG, it would be palaeontologically and geologically important to establish how the two faunal groups are distributed in the eastern arm of Sulawesi. The presence of Lacazinella in this area, however, indicates that some of eastern Sulawesi was derived from the Australian margin, after Eocene times.
Most of the Eocene records from Papua New Guinea show clear differentiation of Lacazinella-only Australian faunas, and APB bearing facies, the latter being clearly part of terrains added later to the modern Papuan island. However there are a number of outcrops and wells with data that do not fit a simple dichotomous model. These sites are all in the area between the Omati Trough and the Chimbu Gorge.
1. Chimbu Gorge
The paper of Crespin (1938) clearly shows Biplanispira, and in two figures there are specimens of Lacazinella in the same view as Biplanispira (plate 2, figs. 15 and 17). This (what?) is the only well-documented case of the two faunal groups co-occurring. As Bain and Binnekamp (1973) and also Rickwood (1955) demonstrated, Lacazinella is common in later Eocene rocks of this area and noone has yet to find any more examples of the APB lineage from this area.
2. The Barikewa-1 well
The publication of the APC (1961, p. 50), in discussing the Eocene, states "The upper section of shoal limestone contained abundant Lacazina, Pellatispira, and rare Discocyclina ..."
3. The Iviri-1 well (APC, drilled 1965, open file report)
A Eocene core in Iviri-1 (core #40) was reported to contain Biplanispira and Pellatispira. On the composite log this core is described as "Brown to dark brown, ill sorted, fine to medium grained calcarenite, slightly silty, much impure black argillaceous material, glauconitic, pellets of dark limestone and claystone which are probably reworked Cretaceous sediments, solubility very variable between 40-95%, fossils few but very significan" Cores 37, 38, 39, and 41 from the same Mendi formation are light grey to brown, without the complex description of core 40 and despite "numerous fossils" the key fossils of Pellatispira and Biplanispira are not recorded in these other cores. A re-examination of the cores would be useful.
4. The Kuru-2 and 3 wells
The publication of the APC (1961, p. 53), in discussing the Eocene, states "The fauna in these bores is characterised by the presence of Discocyclina spp., Biplanispira mirabilis, Spiroclypeus vermicularis and Operculinoides sp. over all but the basal 120 feet. Lacazinella wichmanni supplemented this fauna over all but the topmost 60 feet."