3D assessment of a coral reef at Lalo Atoll reveals varying responses of habitat metrics following a catastrophic hurricane

Extreme disturbances such as hurricanes can cause reductions in coral cover and three-dimensional (3D) structural complexity of coral reefs. We examined changes in structural complexity utilizing 3D reconstruction of a coral-reef site before and after Hurricane Walaka passed through Lalo of the Northwestern Hawaiian Islands. This event resulted in complete destruction of the coral-reef habitat, with dramatic changes in benthic cover from pre-hurricane tabulate coral to post-hurricane rubble. Rugosity and mean slope decreased after the hurricane, while structural complexity, captured by vector ruggedness measure (VRM), showed resolution-specific responses. This metric captured the structural complexity of rubble at a high raster resolution of 1 cm and that of tabulate coral at lower resolutions, resulting in decreases in mean VRM values at 2- and 4-cm resolutions but an increase at 1-cm resolution. Variability in profile and planform curvature was reduced after the hurricane due to a disappearance of extreme curvature values created by the tabulate coral after the hurricane. This study highlights the varying responses of habitat complexity metrics to the complete destruction of a coral reef and provides us with insights into how choices of habitat complexity metrics can affect quantitative assessments of 3D habitat structure.

Paleoecological Significance of a Pre-Mortem Crinoid-Coral Interaction from the Silurian of Southeastern Indiana

A noteworthy specimen recording a syn vivo interaction between a stalked echinoderm and a tabulate coral is described herein from the middle Silurian (Wenlock: Sheinwoodian) Massie Formation of Ripley County, southeastern Indiana. Part of the column of the camerate crinoid Eucalyptocrinites is encrusted around the entirety of its lateral margin by a favositid colony. The radially outward orientation of corallites on both the upper and lower surfaces of the colony show that the coral was elevated completely above the seafloor and, more importantly, that the crinoid column had to be vertical at the time of initial encrustation and subsequent coral astogeny. Hence, the crinoid host was most likely alive throughout the duration of this interaction. No evidence for a paleopathological reaction is present on the crinoid column, suggesting that the encruster did not adversely affect the host. This most likely reflects the long and inflexible column of Eucalyptocrinites, which could have supported encrusting, secondarily tiered organisms—even relatively heavy ones—without interfering with the biological functions of the crown or weighing down the column.

A new mound-building biota from the lower Carboniferous of Alabama

A small (1.2 m) columnar carbonate mound in shaley strata equivalent to the Hartselle Sandstone (lower Serpukhovian) near Woodville, northeastern Alabama, was built by a consortium of species unlike those of other Carboniferous mounds in the southeastern United States. The mound contains a new problematic microencruster, Aphralysia anfracta new species, along with encrusting bryozoans (Fistulipora M'Coy, 1849), nonskeletal microbes, and other microencrusters, including Aphralysia capriorae Mamet and Roux, 1975, in a carbonate mud matrix. Mound cavities are filled with three generations of carbonate and siliciclastic sediment. Other biotic constituents of the mound include oncoids, sponges (including Pileospongia Rigby, Keyes, and Horowitz, 1979), gastropods, crinoids, a tabulate coral, and coenobionts, including coccoid calcimicrobes. The mound biota, especially the microencrusters, is dramatically different from those of other Serpukhovian mounds that have been described from Alabama (made by various consortia of rugose corals, fenestrate bryozoans, crinoids, sponges, and nonskeletal microbes). Indeed, the Woodville mound extends the range of the lower Carboniferous encruster Aphralysia Garwood, 1914 to North America.UUID: http://zoobank.org/d3988875-a7fb-4382-bd14-b17c083d87ad

HUBUNGAN KEPADATAN SIPUT (Drupella) DENGAN KONDISI EKOSISTEM TERUMBU KARANG DI PERAIRAN PULAU SEMUJUR PROVINSI KEPULAUAN BANGKA BELITUNG

This research aims to analyse density of Drupella's on coral reef ecosystem, analyze the percentage of coral cover and analyze the relationship between the density of Drupella with environmental factors and conditions coral reef ecosystem in the waters of Semujur Island. Research data retrieval in April 2019 in the waters of Semujur Island. Drupella data retrieval using Belt Transect method and coral reef data retrieval using Line Intercept Transek. The results showed that the highest overall density of Drupella is in the area of coral, which is 244 ind/100m2 and the lowest density of Drupella is in the landscaped area of 31 ind/100m2, coral cover percentage Highest in the area of coral average of 72.20% and the lowest 23.44% while on the highest cover area of 54.96% and lows of 29.14%. Principal Component Analysis (PCA) in the reef flats and Drupella watersheds correlates with temperature, current, pH, Dissolved Oxygen and Total Suspended Solid. Correspondence Analysis (CA) in the reef flats was found that Drupella was positively correlated with lifeforms acropora submassive, acropora tabulate, coral submassive, and coral massive. In the slope area of the Drupella positively correlated with the type of lifeform acropora digitate, acropora submassive, acropora tabulate, coral submassive, and coral branching.

First record of the tabulate coral "Ligulodictyum" in the early Emsian of Victoria (Australia), with additional data on Australian Ligulodictyum sensu lato

Well-preserved specimens of “Ligulodictyum” belonging to the mauretanicum lineage are described from the lower part of the Taravale Formation, of early Emsian age, Buchan area, eastern Victoria (Australia). A short review of the stratigraphic distribution of Ligulodictyum sensu lato (Ligulodictyum s.l. megastoma and undescribed new species) in central and eastern Victoria is presented. The new data show the presence of the mauretanicum lineage in Victoria, emphasising the relationships between the Tasman Subprovince and the north-western part of the Gondwana (Ibarmaghian Domain).

The oldest species of ?Yavorskia (Tabulata) from the Upper Famennian of the Holy Cross Mountains (Poland)

ABSTRACT Zapalski, M.K. and Berkowski, B. 2012. The oldest species of ?Yavorskia (Tabulata) from the Upper Famennian of the Holy Cross Mountains (Poland). Acta Geologica Polonica, 62 (2), 197-204. Warszawa. A single perfectly preserved colony of a tabulate coral assigned tentatively to the genus Yavorskia Fomitchev, 1931, collected from Upper Famennian beds (Palmatolepis expansa conodont Zone) in a trench located north of the Kowala Quarry (Holy Cross Mts., central Poland) is here described as a new species, ?Y. paszkowskii sp. nov. It differs from other representatives of the genus in the lack of dissepimental structures and in smaller corallite diameters, and may therefore represent the ancestral taxon of this typically early Carboniferous genus. Yavorskia tabulates were apparently migrating eastwards along the southern margin of Laurussia and farther east and north towards Siberia, as they appear in the Famennian in Europe and in the early Carboniferous in the Altaides. Such a conclusion is consistent with previous observations on Early-Middle Devonian pleurodictyform tabulate distribution.

Procteria (Pachyprocteria) vermifera n. sp., an unusual Hicetes-bearing species of tabulate coral from the lower Eifelian of the Gaspé Sandstones Group, Rimouski County (Quebec, Canada)

Procteria (Pachyprocteria) vermifera n. sp. is described from the upper part of the York River Formation (Gaspé Sandstones Group), lower Eifelian (brachiopod Amphigenia Zone), Rimouski County (Quebec, Canada). This new species is considered part of a new lineage of Pachyprocteria characterized by the presence of interstitial corallites. This study reveals for the first time that the granules on the lower (proximal) side are distributed irregularly, their density being higher in the central area of this side than at the periphery. The unusual association of the tabulate coral Procteria (Pachyprocteria) with the “worm” Hicetes is pointed out. The record of the new species adds to the known paleogeographic distribution of Pachyprocteria in North America (Laurussia).