Entobia exogyrarum (Frič, 1883) from the Upper Cretaceous of the Bohemian Cretaceous Basin

The validity of the little-known ichnospecies Entobia exogyrarum (Fri?) is verified. Shells of an oyster, Rhynchostreon suborbiculatum (Lam.), represent the substrate for the sponge borings. The borings occur in many Upper Cenomanian to Middle Turonian localities of the Bohemian Cretaceous Basin. This study revealed that the sponges attacked shells of living oysters. Entobia exogyrarum (Fri?) also represents one of the shallowest occurrences of Entobia borings in the Upper Cretaceous rocks.     

A New Ichnospecies of Gastrochaenolites Leymerie from the Pleistocene Port Morant Formation of Southeast Jamaica and the Taphonomy of Calcareous Linings in Clavate Borings

The ichnospecies Gastrochaenolites pickerilli isp. nov. is based on ten borings found in a shell of the gastropod Strombus gigas Linné from the Pleistocene (Sangamonian) Port Morant Formation of southeast Jamaica. These borings bear morphological similarities to Gastrochaenolites torpedo Kelly and Bromley but differ from all other Gastrochaenolites ispp. in having prominent and numerous calcareous meniscate structures arrayed adjacent to one side of the boring. These menisci are concave towards the center of the boring and are the remnants of calcareous tubes that lined earlier boreholes, that the boring bivalve treated as part of the lithified substrate when relocating. They are thus evidence of the former positions of borings that, unusually, were breached as the bivalve migrated sideways. Although this was a common behavior for Gastrochaenolites-producing bivalves within this substrate, the reason for it occurring is uncertain.     

Ichnofacies and microbial build-ups on Late Miocene rocky shores from Menorca (Balearic Islands), Spain

Angular unconformites between Jurassic and Miocene strata are exposed in the sea cliffs of Cala Cigonya on the northwest coast of Menorca in the Balearic Islands of Spain. The geological discontinuities represent rocky shores on opposite sides of a former headland with 15 m of topographic relief. On the east flank, Jurassic dolomite is overlain by Upper Miocene (Tortonian to Messinian) breccia and laminated limestone. Here, a partially exhumed dolomite surface records Miocene bivalve borings of the ichnospecies Gastrochaenolites torpedo and G. lapidicus that achieved a density of >1,000 borings/m². Other associated traces include sponge borings (Entobia isp.) and polychaete borings (Caulostrepsis isp.). A breccia deposit 0.8 m thick was derived from the underlying dolomite and angular clasts still retain evidence of bivalve borings. Above follows a succession of laminated limestone beds more than 5 m thick, including some levels with dome-shaped stromatolites and other horizons with reworked dolomite clasts. Thin-section analysis of the laminated limestone reveals dark and light couplets 0.2 mm thick consistent with microbial origins. In contrast, the west flank was buried by coarse sandstone and laminated sediments. Here, dwelling structures of regular echinoids (Circolites kotoncensis) are the dominant traces preserved on the dolomite surface, reaching a maximum density of 66 borings/m². Associated borings include Entobia geometrica as well as rare traces of Gastrochaenolites isp. and Trypanites isp. Notable for the absence of a basal Miocene breccia, the west flank is interpreted as a sheltered rocky shore coeval with an exposed rocky shore on the east flank. Today, heavy surf on the north coast of Menorca is related to the Tramontana winds that blow out of Spain during winter months. Similar atmospheric circulation patterns must have prevailed during the Late Miocene, but the replacement of ichnofacies by microbial build-ups resulted from increased salinity during the Messinian crisis.     

Oichnus Bromley Borings in the Irregular Echinoid Hemipneustes Agassiz from the Type Maastrichtian (Upper Cretaceous,The Netherlands and Belgium)

Three ichnospecies of Oichnus Bromley occur in tests of the large holasteroid echinoid Hemipneustes striatoradiatus (Leske) in the type area of the Maastrichtian (Upper Cretaceous) in The Netherlands and Belgium; Oichnus simplex Bromley (penetrative), Oichnus paraboloides Bromley (nonpenetrative and showing two distinct morphologies), and Oichnus excavatus isp. nov. (nonpenetrative). The two distinct morphologies of O. paraboloides (both shallow, one with a central boss) are gregarious, but do not occur together on the same specimens, suggesting they were generated by different taxa. Oichnus paraboloides with a central boss occurs on H. striatoradiatus from the upper Nekum Member, Maastricht Formation (Maastrichtian, Upper Cretaceous). Tests of the host echinoid are smaller in the overlying Meerssen Member, Maastricht Formation, where they are infested by O. excavatus, the largest borings considered herein, which have concave walls and a large central boss. Blisters inside tests from the Meerssen Member show that this infestation occurred when the echinoid was alive. It is postulated that producers of these borings in H. striatoradiatus may have been genetically related and increased in size during the Maastrichtian even as the host echinoids showed a size decrease. This size increase in H. striatoradiatus was genetic and cannot be related to increase in size of borings.     

Host‐specific acrothoracid barnacles on Middle Devonian platyceratid gastropods

Borings, attributed to acrothoracic barnacles, occur on the platyceratid gastropod Naticonema lineatum (Conrad) from the Middle Devonian Hamilton Group of western New York and rarely in specimens as old as the Early Devonian. These latter are the oldest known acrothoracid borings are in the fossil record. The borings are consistently developed as laterally compressed, inequilateral pouches exclusively on these gastropods, commonly as dense infestations.

Naticonema shells yielding borings typically occur associated with partially articulated qrinoid remains, and they are sometimes found attached to crinoids in a manner similar to coprophagous Platyceras. In addition to barnacle borings, Naticonema shells often bear thin encrustations of bryozoans which are usually perforated by these borings but sometimes also overgrow them. Barnacles bored live hosts; gastropods prevented shell penetration by producing cyst‐like secondary secretions of calcite beneath acrothoracid boreholes.

The relative antiquity of these borings and their association with coprophagous platyceratids makes their discovery particularly significant in revealing aspects of the early ecology of barnacles. Attachment to the host commensal gastropods was one of the first successful life modes of these crustaceans prior to their later diversification to other habitats. Mississippian and Pennsylvanian occurrences of similarly bored gastropods demonstrate continuity of the barnacle‐gastropod‐crinoid ecological association from the Middle to Late Paleozoic.     

Bioerosive structures from Miocene marine mobile‐substrate communities in southern Spain,and description of a new sponge boring

Abstract: Neogene palaeoshore sediments are abundantly represented along the Mediterranean coast of Iberia. An outcrop north of the Sierra Tejeda, named La Resinera, exposes concentrations of pebbles and boulders of marble, comprising an upper Miocene marine beach deposit. The high diversity of bioerosion trace fossils present in these boulders includes structures produced by polychaete annelids, demosponges, echinoids and endolithic bivalves, which indicate a shallow shoreface environment. The ichnotaxa represented are Maeandropolydora sulcans, Caulostrepsis taeniola, Entobia geometrica, Entobia ovula, Circolites kotoncensis, Gastrochaenolites torpedo, Gastrochaenolites lapidicus, Gastrochaenolites ornatus and Gastrochaenolites turbinatus. The borings are Tortonian (late Miocene) in age. Also present, and particularly abundant, are large sponge borings that have a single chamber from which radiating canals emerge. This trace fossil is designated as Entobia resinensis isp. nov.     

Bioerosion of oyster shells in brackish modern mangrove swamps,Nigeria

Studies on shells of the intertidal oyster Crassostrea tulipa cemented to aerial prop roots and stems of the mangroves Rhizo‐phora racemosa, R. harrisonii, and R. mangle from the Cross River and Qua Iboe River estuaries show that photosynthetic en‐dolithic cyanobacteria (blue‐greens) are the major bioerosional agent, affecting about 94% of the shells examined. Pblychaetes attacked less than 10% of these materials and thus have low bioerosional impact.

Herbivorous gastropods play a secondary role because, by grazing, they clear the shell surface of encrusting cyanobacteria and thus enhance the activity of boring forms. Where epilithic cyanobacteria have been removed, the gastropods sometimes leave faint grazing traces of low fossilization potential.

Microfloral boring activity is high at all stations, but the assemblage is of markedly low diversity compared with those of littoral and shallow sublittoral marine communities and may thus be useful as a paleoenvironmental tool. Bioerosional agents are directly or indirectly responsible for the disintegration of oyster shells, whose fragments are incorporated in muddy intertidal sediments.     

The sclerobionts of the Bajocian Oolithe ferrugineuse de Bayeux Formation from Calvados (Paris Basin,Normandy, France)

Silicified fossils collected in ploughed fields at Gavrus (Calvados, France), mainly mollusc shells, are Bajocian in age, and come from the Oolithe ferrugineuse de Bayeux Formation. The entire formation is highly condensed and most fossils are reworked. Their silicification allowed treatment with dilute hydrochloric acid. This treatment brought to light numerous encrusting sclerobionts: Porifera (3 taxa), Bryozoa (n), Polychaeta (9), Brachiopoda (n), Bivalvia (5). The borings and bioerosional traces are described using the “categories of architectural design” as defined by Buatois et al. (2017). Among the 28 ichnotaxa described (corresponding to an ichnodisparity of 14), Planavolites wisshaki isp. nov., Kleithrichnus belemnophilus igen. nov., isp. nov. and Foggara foggara igen. nov., isp. nov. are new. Some Gastrochaenolites dijugus Kelly and Bromley, 1984 borings accommodate the shell of the presumed borer Lithophaga fabella J.-A. Eudes-Deslongchamps, 1838. A group of Nododendrina europaea (Fischer, 1875) on a belemnite rostrum provides a good instance of an ichnogenetic series. Encrusting sclerobionts and macroscopic boring and bioerosional trace-makers are dominantly suspension feeders. The ichnofacies is a peculiar Entobia-ichnofacies, found in deeper, lower-energy environments than the “classical” coastal Entobia-ichnofacies, on deep shell-grounds far from the coast, in the deep euphotic zone.     

Holes in Bones: Ichnotaxonomy of Bone Borings

Bone is a substrate for bioerosion at equal rank with xylic and lithic substrates. Accordingly, borings in bone have to be identified in an analogous way to other ichnogenera coined for one type of substrate. In due course, the new ichnogenera Osteichnus n. igen. and Clavichnus n. igen. are established within the new ichnofamily Osteichnidae. Gastrochaenolites and Trypanites are here restricted to lithic substrates, and Asthenopodichnium only occurs in xylic substrates. Only with this approach, ichnotaxobases of trace fossils in bone are identical to those in other hard substrates. Cuniculichnus variabilis n. igen. n. isp. is introduced for variably shaped pits to tunnels bored into bone by beetle (arguably dermestid) larvae; its ethological character is close to a pupichnion.     

Bioerosion of gastropod shells: with emphasis on effects of coralline algal cover and shell microstructure

Organisms boring into fifty nine species of gastropod shells on reefs around Guam were the bryozoan Penetrantia clionoides; the acrothoracian barnacles Cryptophialus coronorphorus, Cryptophialus zulloi and Lithoglyptis mitis; the foraminifer Cymbaloporella tabellaeformis, the polydorid Polydora sp. and seven species of clionid sponge. Evidence that crustose coralline algae interfere with settlement of larvae of acrothoracian barnacles, clionid sponges, and boring polychaetes came from two sources: (1) low intensity of boring in limpet shells, a potentially penetrable substrate that remains largely free of borings by virtue of becoming fully covered with coralline algae at a young age and (2) the extremely low levels of boring in the algal ridge, a massive area of carbonate almost entirely covered by a layer of living crustose corallines. There was a strong negative correlation between microstructural hardness and infestation by acrothoracian barnacles and no correlation in the case of the other borers. It is suggested that this points to a mechanical rather than a chemical method of boring by the barnacles. The periostracum, a layer of organic material reputedly a natural inhibitor of boring organisms, was bored by acrothoracican barnacles and by the bryozoan. The intensity of acrothoracican borings is shown to have no correlation with the length of the gastropod shell.     

Epi- and endobiontic organisms on Late Jurassic crinoid columns from the Negev Desert, Israel: Implications for co-evolution

Columns of the articulate crinoids Millericrinus and Apiocrinites from the Upper Jurassic (Upper Callovian) Zohar and Matmor formations of the Negev Desert of Israel display abundant encrusting organisms of about ten species, as well as diverse trace fossils produced by endobionts. Pluricolumnals were colonized by epi- and endobiontic organisms both during life and post-mortem. Skeletonized encrusting organisms include abundant ostreid bivalves (which evidently colonized both live and dead crinoid columnals), two types of serpulid worms, encrusting foraminifera, three species of bryozoans, and small encrusting sclerosponges. Several types of borings are present: Trypanites (possibly produced by sipunculids), Gastrochaenolites (crypts of boring lithophagid bivalves), elliptical barnacle? borings, and channel-like annelid? borings. In addition, approximately 16% of the pluricolumnals display circular parabolic embedment pits assignable to the ichnogenus Tremichnus. They are associated with substantial deformation of the containing columnals and were probably the work of host-specific ectoparasitic organisms. Discovery of Tremichnus on Jurassic crinoids extends the range of this trace by almost 100 million years, providing evidence for one of the longest-ranging host-parasite interactions documented thus far (over 200 million years). The relationship of epibionts to the Jurassic crinoids thus ranged from simple utilization of dead hard substrate to probable opportunistic commensalism in forms that colonized the live upright stems, as in some oysters, through host-specific parasitism in the case of Tremichnus.     

中国湘南早侏罗世双壳类壳体内的遗迹化石--兼论遗迹化石属Talpina Hagenow, 1840

论文描述的双壳类壳体内的钻孔遗迹组合发现于湖南省东南部宜章县下坪附近的心田门组上部(早侏罗世,早辛涅缪尔期)浅海沉积地层中。这个遗迹化石群中,帚虫类动物制造的钻孔Talpinahunanensisichnosp.nov.(新遗迹化石种)明显地占据了大部分,偶尔共生的其它钻孔包括:Rogerellaichnosp.(蔓足亚纲尖胸类的遗迹)、Calcideletrixichnosp.(可能是藻类的遗迹)、藻或菌造的遗迹(暂定为"Mycelites"ichnosp.)、以及一种可能被海绵动物制造的未定钻孔。生物侵蚀者侵害了海底上较大的双壳类壳体。钻孔保存为天然印模(石核),它们是文石质壳体溶解后留下的空间中的充填物。此外,文中还讨论了遗迹化石属TalpinaHagenow,1840,尤其讨论了有关遗迹种颇为复杂的鉴别问题,同时校正了该遗迹属的属征。     

Bored and Burrowed: An Unusual Echinoid Steinkern from the Type Maastrichtian (Upper Cretaceous,Belgium)

A test of the irregular echinoid Hemipneustes striatoradiatus (Leske) was dissolved in dilute hydrochloric acid to expose the flint steinkern. This revealed slender, string-like borings that were mainly limited to ambulacra (Talpina isp. cf. T. canna (Price)); less common pouch-like borings limited to part of one ambulacrum only (Rogerella isp. cf. R. pattei (Saint Seine)); and slender, sinuous to contorted burrows, Planolites montanus Richter. Ingress to the test (borers) and sediment infill (burrowers) was presumably through the ambulacral pore pairs of the dead test. Borings and burrows were probably not coeval. Such infestations of fossil echinoids may be locally common, but their identification is controlled by the difficulty of seeing features of both the test and the infill.     

Bivalve borings in Lower Jurassic Lithiotis fauna from northeastern Italy and its palaeoecological interpretation

Random shell sections of the Pliensbachian (Early Jurassic) larger bivalve Opisoma from columns within the Main Post Office building of Ferrara, northern Italy, have been discovered to bear neat clavate-shape boreholes. These boreholes belong to the ichnogenus Gastrochaenolites Leymerie and represent bivalve borings. Opisoma is a subordinate component of the Lithiotis fauna characterised by aberrant shells thriving in tropical lagoonal settings which were widespread throughout the Tethyan and Panthalassa coasts. Although the Lithiotis fauna is well known in the palaeontological literature, no bivalve boring have been so far been formally described. The uniqueness of the morphology, size and substrate of these borings merits the designation of the new species Gastrochaenolites messisbugi ichnosp. nov. which thereby represents the first ichnospecies described from this fauna. The morphology of the boreholes and the included bivalves allows the boring activity to be ascribed to a mytilid bivalve. Palaeoecological and taphonomic analyses allowed the presence of the boreholes to be correlated to the Opisoma mode of life (epifaunal, free-living form) as well as to generally low sedimentation rates and seasonal mesotrophic conditions during an overall oligotrophic regime.

http://zoobank.org/urn:lsid:zoobank.org:act:CCF77B32-D459-4305-BC86-93F228852E50     

Two modes of mitochondrial dysfunction lead independently to lifespan extension in Caenorhabditis elegans

In Caenorhabditis elegans, longevity is increased by a partial loss‐of‐function mutation in the mitochondrial complex III subunit gene isp‐1. Longevity is also increased by RNAi against the expression of a variety of mitochondrial respiratory chain genes, including isp‐1, but it is unknown whether the isp‐1(qm150) mutation and the RNAi treatments trigger the same underlying mechanisms of longevity. We have identified nuo‐6(qm200), a mutation in a conserved subunit of mitochondrial complex I (NUDFB4). The mutation reduces the function of complex I and, like isp‐1(qm150), results in low oxygen consumption, slow growth, slow behavior, and increased lifespan. We have compared the phenotypes of nuo‐6(qm200) to those of nuo‐6(RNAi) and found them to be distinct in crucial ways, including patterns of growth and fertility, behavioral rates, oxygen consumption, ATP levels, autophagy, and resistance to paraquat, as well as expression of superoxide dismutases, mitochondrial heat‐shock proteins, and other gene expression markers. RNAi treatments appear to generate a stress and autophagy response, while the genomic mutation alters electron transport and reactive oxygen species metabolism. For many phenotypes, we also compared isp‐1(qm150) to isp‐1(RNAi) and found the same pattern of differences. Most importantly, we found that, while the lifespan of nuo‐6, isp‐1 double mutants is not greater than that of the single mutants, the lifespan increase induced by nuo‐6(RNAi) is fully additive to that induced by isp‐1(qm150), and the increase induced by isp‐1(RNAi) is fully additive to that induced by nuo‐6(qm200). Our results demonstrate that distinct and separable aspects of mitochondrial biology affect lifespan independently.     

Site Selectivity of the Pit Oichnus excavatus Donovan and Jagt Infesting Hemipneustes striatoradiatus (Leske) (Echinoidea) in the Type Maastrichtian (Upper Cretaceous,The Netherlands)

Two tests of the holasteroid echinoid Hemipneustes striatoradiatus (Leske) from the type area of the Maastrichtian Stage (Upper Cretaceous) bear a varied infestation of episkeletozoans (oysters, bryozoan colony, and serpulids), borings (probable Caulostrepsis isp., Oichnus simplex Bromley), surface abrasion (Gnathichnus? isp.), and pits (O. excavatus Donovan and Jagt). Only O. excavatus represents a premortem infestation. In one specimen, the four individual pits of this ichnospecies are each associated with a different ambulacrum and pore pairs that, in life, bore respiratory tube feet; the anterior ambulacrum, of different gross morphology, is not infested. In the second test, three out of four of the same ambulacra are infested, although there are also O. excavatus in the interambulacra. The association between O. excavatus and the ambulacra of the echinoid, and thus its tube feet, is open to several plausible explanations, but most likely provided some form of feeding or protective advantage to the pit-forming organism.     

Olfactory response of Costelytra zealandica (Coleoptera: Melolonthinae) to the roots of several pasture plants

The influence of natural plant odours on the locomotory behaviour of 3rd‐instar larvae of Costelytra zealandica (White) was studied by observing their movement in glass‐sided test chambers. Through an analysis of the paths followed by individual larvae in single‐option choice‐chamber tests it was possible to evaluate the responses of the larvae to different plant materials. The odour of fresh young perennial ryegrass (Loliumperenne) root was more attractive to the insects than was that of older plants. Larvae were also more strongly attracted to the root of lucerne (Medicago sativa), Lotus pedunculatus, red clover (Trifolium pratense), and white clover (T. repens) than to that of perennial ryegrass. The possible role of volatile chemical factors in plant resistance to grass grub attack is discussed.     

Ichnospecies Teredolites longissimus and Teredinid Body Fossils from the Early Eocene of India—Taphonomic and Palaeoenvironmental Implications

Extensively bored log-grounds with ichnospecies Teredolites longissimus and body fossils of the causative teredinid molluscs are recorded from the Early Eocene subsurface beds of the Cambay Shale Formation at Vastan lignite Mine in western India. Three sizes of T. longissimus observed in Vastan mostly represent animals in different stages of maturity or successive infestation of substrate. Orientation of a majority of small borings suggests that teredinid larvae preferred to initiate boring across the wood grain and subsequently turned to become parallel to grain exhibiting adult boring behavior. Variations in morphology of recovered shells indicate involvement of at least two teredinid taxa in constructing T. longissimus from Vastan—one is identified as Bankia isp. based on pallets and the other remains unidentified and may possibly represent another bankiine, Nototeredo. Evidences of traumatic as well as attritional mortality are noticeable. The xylic substrates having affinity with woods of a modern tree genus Aglaia (Meliaceae) were apparently transported from their natural habitat of an inland moist tropical forest to the coastal region where they were colonized by the teredinid bivalves. The profusely infested wood logs were buried in a near shore lagoon or a tidal flat setting, which is corroborated by the known biota (vertebrate, invertebrate as well as plants) as well as sedimentary facies of the Cambay Shale Formation in Vastan section.     

Palaeocology of Hard Substrate Faunas from the Cretaceous Qahlah Formation of the Oman Mountains

Skeletal encrusters and carbonate hardgrounds are rare in siliciclastic sands and gravels because of high levels of abrasion and sediment movement. An exception to this is the Maastrichtian Qahlah Formation of the Oman Mountains, a sequence of coarse siliciclastic sediments deposited on a shallow marine shelf above wavebase and at an equatorial palaeolatitude. This unit contains intercalated carbonate hardgrounds and other hard substrates which were encrusted and bored. The hard substrates, comprising carbonate and silicate clasts, calcareous bioclasts (mollusc shells and coral fragments) and wood, supported a diverse encrusting and boring fauna dominated in biomass by the oyster Acutostrea . There are twelve bryozoan species and at least two serpulid worm species, most living cryptically. Other encrusters on exposed surfaces include the agglutinated foraminiferan Placopsilina and several species of colonial corals. Borings in the carbonate clasts and shells are predominantly those of bivalves ( Gastrochaenolites ), with subsidiary clionid sponge ( Entobia ) and acrothoracican barnacle ( Rogerella ) borings. The woodgrounds are thoroughly bored by teredinid bivalves ( Teredolites ). Of the common substrate types, carbonate hardground clasts support the greatest number of taxa, followed by chert clasts, with limestone rockground pebbles being depauperate. Clast composition and relative stability probably explain these differences. Individual clasts probably had variable and typically long colonisation histories. Detailed palaeoecological interpretation is constrained by taphonomic loss, time-averaging and clast transportation and reorientation. Evidence from the Qahlah Formation shows that tropical rocky-shore biotas in the Cretaceous were not impoverished as previously believed.     

Determination of a Late Miocene rocky palaeoshore by bioerosion trace fossils from the Bozcaada Island, Çanakkale,Turkey

Bioerosion is a common process in hard substrates. This study introduces an example from the rocky palaeoshore cropping out at a sea cliff on the Bozcaada Island. It includes bioerosion trace fossils preserved in limestone boulders of the shallow marine and lacustrine Alcitepe Formation of Late Miocene age. The ichnotaxa include borings produced by duraphagous drillers (Oichnus isp.), phonorids (cf. Conchotrema isp.), clionid sponges (Entobia cf. goniodes, Entobia geometrica, Entobia laquea, Entobia ovula, E. cf. solaris, Entobia isp.), endolithic bivalves (Gastrochaenolites torpedo, Gastrochaenolites lapidicus, Gastrochaenolites isp., Phrixichnus isp.), polychaete annelids (Maeandropolydora isp., Maeandropolydora sulcans, Maeandropolydora decipiens, Caulostrepsis taeniola, Caulostrepsis isp.), echinoids (cf. Circolites isp.) and spinculid worms (cf. Trypanites isp.). Barnacles are also common as encrusters. The borings can be ascribed to the Gastrochaenolites-Entobia assemblage, which is typical of Neogene rocky-shores. They belong to the Entobia ichnofacies indicating various conditions of light, energy, and depth. Therefore they can reveal environmental changes and play an important role in forming palaeo-rocky shores and wave-cut platforms during marine trangressive events.