Ontogenetic trajectories of direct and indirect defenses of myrmecophytic plants colonized either by mutualistic or opportunistic ant species

Abstract Despite the paleontological relevance and paleobiological interest of trigoniid bivalves, our knowledge of their ontogeny—an aspect of crucial evolutionary importance—remains limited. Here, we assess the intra- and interspecific ontogenetic variations exhibited by the genus Steinmanella Crickmay (Myophorellidae: Steinmanellinae) during the early Valanginian–late Hauterivian of Argentina and explore some of their implications. The (ontogenetic) allometric trajectories of seven species recognized for this interval were estimated from longitudinal data using 3D geometric morphometrics, segmented regressions, and model selection tools, and then compared using trajectory analysis and allometric spaces. Our results show that within-species shell shape variation describes biphasic ontogenetic trajectories, decoupled from ontogenetic changes shown by sculpture, with a gradual decay in magnitude as ontogeny progresses. The modes of change characterizing each phase (crescentic growth and anteroposterior elongation, respectively) are conserved across species, thus representing a feature of Steinmanella ontogeny; its evolutionary origin is inferred to be a consequence of the rate modification and allometric repatterning of the ancestral ontogeny. Among species, trajectories are more variable during early ontogenetic stages, becoming increasingly conservative at later stages. Trajectories’ general orientation allows recognition of two stratigraphically consecutive groups of species, hinting at a potentially higher genus-level diversity in the studied interval. In terms of functional morphology, juveniles had a morphology more suited for active burrowing than adults, whose features are associated with a sedentary lifestyle. The characteristic disparity of trigoniids could be related to the existence of an ontogenetic period of greater shell malleability betrayed by the presence of crescentic shape change.

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Tomato Below Ground–Above Ground Interactions: Trichoderma longibrachiatum Affects the Performance of Macrosiphum euphorbiae and Its Natural Antagonists

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-02-13-0059-r ◽

2013 ◽

Vol 26 (10) ◽

pp. 1249-1256 ◽

Cited By ~ 39

Author(s):

Donatella Battaglia ◽

Simone Bossi ◽

Pasquale Cascone ◽

Maria Cristina Digilio ◽

Juliana Duran Prieto ◽

...

Keyword(s):

Tomato Plant ◽

Integrated Control ◽

Macrosiphum Euphorbiae ◽

Aphidius Ervi ◽

Aphid Parasitoid ◽

Trichoderma Longibrachiatum ◽

Indirect Defenses ◽

Plant Growth Promoting ◽

Below Ground ◽

Species Specific

Below ground and above ground plant–insect–microorganism interactions are complex and regulate most of the developmental responses of important crop plants such as tomato. We investigated the influence of root colonization by a nonmycorrhizal plant-growth-promoting fungus on direct and indirect defenses of tomato plant against aphids. The multitrophic system included the plant Solanum lycopersicum (‘San Marzano nano’), the root-associated biocontrol fungus Trichoderma longibrachiatum strain MK1, the aphid Macrosiphum euphorbiae (a tomato pest), the aphid parasitoid Aphidius ervi, and the aphid predator Macrolophus pygmaeus. Laboratory bioassays were performed to assess the effect of T. longibrachiatum MK1, interacting with the tomato plant, on quantity and quality of volatile organic compounds (VOC) released by tomato plant, aphid development and reproduction, parasitoid behavior, and predator behavior and development. When compared with the uncolonized controls, plants whose roots were colonized by T. longibrachiatum MK1 showed quantitative differences in the release of specific VOC, better aphid population growth indices, a higher attractiveness toward the aphid parasitoid and the aphid predator, and a quicker development of aphid predator. These findings support the development of novel strategies of integrated control of aphid pests. The species-specific or strain-specific characteristics of these below ground–above ground interactions remain to be assessed.

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Developmental Changes in Direct and Indirect Defenses in the Young Leaves of the Neotropical Tree GenusInga(Fabaceae)

Biotropica ◽

10.1111/j.1744-7429.2012.00914.x ◽

2012 ◽

Vol 45 (2) ◽

pp. 175-184 ◽

Cited By ~ 13

Author(s):

Ryan J. Bixenmann ◽

Phyllis D. Coley ◽

Tom A. Kursar

Keyword(s):

Developmental Changes ◽

Indirect Defenses ◽

Neotropical Tree ◽

Young Leaves

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Compaction-related deformation in Cambrian olenelloid trilobites and its implications for fossil morphometry

Journal of Paleontology ◽

10.1017/s0022336000027827 ◽

1999 ◽

Vol 73 (2) ◽

pp. 355-371 ◽

Cited By ~ 40

Author(s):

Mark Webster ◽

Nigel C. Hughes

Keyword(s):

Lower Cambrian ◽

Shape Change ◽

Anterior Lobe ◽

Interspecific Differences ◽

Fracture Patterns ◽

Morphometric Analyses ◽

Ontogenetic Trajectories ◽

Metric Distances ◽

Relative Convexity ◽

Shape Changes

Morphometric analyses of silicified and nonsilicified (preserved in shale) specimens of the olenelloid trilobites Olenellus (Olenellus) gilberti Meek (in White, 1874) and Nephrolenellus geniculatus Palmer, 1998, from the Lower Cambrian C-Shale Member of the Pioche Formation show that even well-preserved specimens in shales have undergone significant changes in lateral as well as vertical dimensions as a result of compaction. Analyses of cephalic landmarks show that in both species compaction causes posteriordirected collapse of the anterior lobe of the glabella, adaxial deformation of the ocular lobes, and abaxial and anterior splaying of genal regions. These shape changes are explicable in terms of observed exoskeletal fracture patterns. Landmarks show an increase in scatter around their ontogenetic trajectories that is generally proportional to the degree of lateral shift each landmark has undergone. Interspecific differences in compactional response may depend on the relative convexity of the cephalon. Olenellus (Olenellus) gilberti is a low-convexity species and shows marked lateral shape change, particularly in the genal region. Nephrolenellus geniculatus is more convex and shows less severe lateral shape change. Landmarks of both species exhibit an average trebling of the degree of scatter around their average ontogenetic trajectories in compacted samples. Because even well-preserved specimens in shales differ in shape from their precompactional appearance, results of morphometric studies utilizing metric distances between landmarks in trilobites where compaction can be detected must be interpreted with caution.

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New specimen of <i>Cacops woehri</i> indicates differences in the ontogenetic trajectories among cacopine dissorophids

Fossil Record ◽

10.5194/fr-18-73-2015 ◽

2015 ◽

Vol 18 (1) ◽

pp. 73-80 ◽

Cited By ~ 6

Author(s):

N. B. Fröbisch ◽

A. Brar ◽

R. R. Reisz

Keyword(s):

Morphological Changes ◽

Lower Permian ◽

Ecological Diversity ◽

Large Specimen ◽

Skull Morphology ◽

Skull Shape ◽

Ontogenetic Trajectories ◽

Ontogenetic Trajectory ◽

Taxic Diversity

Abstract. The Lower Permian Dolese locality has produced numerous exquisitely preserved tetrapod fossils representing members of a lower Permian upland fauna. Therein, at least nine taxa of the clade Dissorophoidea, ranging in size from the large predaceous trematopid Acheloma to the miniaturized amphibamid Doleserpeton, highlight the great taxic and ecological diversity of this anamniote clade. Here we describe a large specimen of the dissorophid Cacops woehri, which was previously only known from the juvenile or subadult holotype skull. Another member of the genus Cacops present at the Dolese locality, Cacops morrisi, is also represented by specimens spanning juvenile, subadult, and adult stages, allowing for a comparison of morphological changes taking place in the late phases of the ontogenetic trajectory of cacopine dissorophids. The new find shows that, in contrast to C. morrisi and C. aspidephorus, C. woehri only undergoes relatively subtle changes in skull morphology in late ontogeny and retains the overall more gracile morphology into adult stages. This includes retention of the rather shallow skull shape as well as a pattern of sculpturing consisting of elongate ridges and grooves and a large occipital flange. This suggests somewhat different functional demands in C. woehri than in other known species of Cacops, possibly associated with a different ecology paralleling the great taxic diversity of dissorophoids at the Dolese locality.

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On the morphospace of eurypterine sea scorpions

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s175569102100030x ◽

2021 ◽

pp. 1-6

Author(s):

Russell D. C. BICKNELL ◽

Lisa AMATI

Keyword(s):

New Taxa ◽

Compound Eye ◽

Developmental Changes ◽

Apex Predators ◽

Geometric Morphometric ◽

Eye Morphology ◽

Morphometric Analyses ◽

Ontogenetic Trajectories ◽

Landmark Analyses ◽

Shape Data

ABSTRACT Eurypterids (sea scorpions) are a group of extinct, marine euchelicerates that have an extensive Palaeozoic record. Despite lacking a biomineralised exoskeleton, eurypterids are abundantly preserved within select deposits. These collections make statistical analyses comparing the morphology of different genera possible. However, eurypterid shape has not yet been documented with modern geometric morphometric tools. Here, we summarise the previous statistical assessments of eurypterid morphology and expand this research by presenting landmark and semi-landmark analyses of 115 eurypterid specimens within the suborder Eurypterina. We illustrate that lateral compound eye morphology and position drives specimen placement in morphospace and separates proposed apex predators from more generalist forms. Additionally, evidence for size clusters in Eurypterus that may reflect ontogeny is uncovered. We highlight the use of geometric morphometric analyses in supporting the naming of new taxa and demonstrate that these shape data represent a novel means of understanding inter-generic ontogenetic trajectories and uncovering developmental changes within the diverse euarthropod group.

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Polyphenol-Rich Purple Corn Pericarp Extract Adversely Impacts Herbivore Growth and Development

Insects ◽

10.3390/insects11020098 ◽

2020 ◽

Vol 11 (2) ◽

pp. 98 ◽

Cited By ~ 4

Author(s):

Mandeep Tayal ◽

Pavel Somavat ◽

Isabella Rodriguez ◽

Tina Thomas ◽

Bradley Christoffersen ◽

...

Keyword(s):

Hormonal Regulation ◽

Growth And Development ◽

Control Diet ◽

Insect Pest ◽

Plant Secondary Metabolites ◽

Mass Gain ◽

Developmental Time ◽

Egg Hatching ◽

Indirect Defenses ◽

Purple Corn

Plant secondary metabolites such as terpenes, phenolics, glycosides, and alkaloids play various functional roles including pigmentation, foliar and floral volatile synthesis, hormonal regulation, and direct and indirect defenses. Among these, phenolic compounds are commonly found in plants, but vary in the distribution of their specific compounds among plant families. Polyphenols, including anthocyanins and tannins, are widely distributed and have been well documented for their roles- primarily in plant pigmentation and also in plant defenses. However, commercialization of such compounds for use in insect pest management is severely hampered by expensive, inefficient, and time-consuming extraction protocols. Using a recently developed inexpensive and easy extraction method using the byproducts of pigmented (purple) corn processing, we examined whether the crude pericarp extract rich in polyphenols can affect the growth and development of tobacco hornworm (Manduca sexta L.) caterpillars. Our findings show that purple corn pericarp extract negatively affected M. sexta egg hatching and larval mass gain and prolonged developmental time compared to regular yellow corn extract or an artificial control diet. We also found that these effects were more severe during the early stages of caterpillar development. These results conclusively demonstrate that purple corn pericarp, an inexpensive by-product of the corn milling industry, is a valuable product with excellent potential as an insect antifeedant.

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