Connecting pattern to process: Growth of spiral shell sculpture in the gastropod <i>Nucella ostrina</i> (Muricidae: Ocenebrinae)

Webster, Nicole B.; Palmer, A. Richard

doi:10.1111/ede.12265

Cited by 5 publications

(5 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In extant bivalves, longitudinal ribs have been linked to the presence of raised and thick portions of the mantle surface called corposa spinosa [84,85]. In the gastropod Nucella ostrina, the mantle margin has been observed to be scalloped or ruffled but not particularly thickened [86]. Each longitudinal rib in Nucella ostrina has been shown to be associated with a tongue-shaped extension of the mantle in the growth direction [86].…”

Section: Morphogenesis Of Lateral Ribs and Spinesmentioning

confidence: 99%

“…In the gastropod Nucella ostrina, the mantle margin has been observed to be scalloped or ruffled but not particularly thickened [86]. Each longitudinal rib in Nucella ostrina has been shown to be associated with a tongue-shaped extension of the mantle in the growth direction [86]. Longitudinal ribs in this dimorphic gastropod were produced by changes in size of the active mantle and epithelial cell morphology [86], the ribbed shells showing a larger elongation in the direction of growth of the outer epithelium as well as an increase in cell height compared to smooth shells of the same species.…”

Section: Morphogenesis Of Lateral Ribs and Spinesmentioning

confidence: 99%

“…Each longitudinal rib in Nucella ostrina has been shown to be associated with a tongue-shaped extension of the mantle in the growth direction [86]. Longitudinal ribs in this dimorphic gastropod were produced by changes in size of the active mantle and epithelial cell morphology [86], the ribbed shells showing a larger elongation in the direction of growth of the outer epithelium as well as an increase in cell height compared to smooth shells of the same species. Similarly, intraspecific variation in spine length in another neogastropod, Hexaplex trunculus, seems to be dependent on the variation in length of the outer mantle fold in the growth direction along the mantle edge [80].…”

Section: Morphogenesis Of Lateral Ribs and Spinesmentioning

confidence: 99%

See 2 more Smart Citations

Learning from beautiful monsters: phylogenetic and morphogenetic implications of left-right asymmetry in ammonoid shells

et al. 2019

View full text Add to dashboard Cite

Background: Many pathologies that modify the shell geometry and ornamentation of ammonoids are known from the fossil record. Since they may reflect the developmental response of the organism to a perturbation (usually a sublethal injury), their study is essential for exploring the developmental mechanisms of these extinct animals. Ammonoid pathologies are also useful to assess the value of some morphological characters used in taxonomy, as well as to improve phylogenetic reconstructions and evolutionary scenarios. Results: We report on the discovery of an enigmatic pathological middle Toarcian (Lower Jurassic) ammonoid specimen from southern France, characterized by a pronounced left-right asymmetry in both ornamentation and suture lines. For each side independently, the taxonomic interpretations of ornamentation and suture lines are congruent, suggesting a Hildoceras semipolitum species assignment for the left side and a Brodieia primaria species assignment for the right side. The former exhibits a lateral groove whereas the second displays sinuous ribs. This specimen, together with the few analogous cases reported in the literature, lead us to erect a new forma-type pathology herein called "forma janusa" for specimens displaying a left-right asymmetry in the absence of any clear evidence of injury or parasitism, whereby the two sides match with the regular morphology of two distinct, known species. Conclusions: Since "forma janusa" specimens reflect the underlying developmental plasticity of the ammonoid taxa, we hypothesize that such specimens may also indicate unsuspected phylogenetic closeness between the two displayed taxa and may even reveal a direct ancestor-descendant relationship. This hypothesis is not, as yet, contradicted by the stratigraphical data at hand: in all studied cases the two distinct taxa correspond to contemporaneous or sub-contemporaneous taxa. More generally, the newly described specimen suggests that a hitherto unidentified developmental link may exist between sinuous ribs and lateral grooves. Overall, we recommend an integrative approach for revisiting aberrant individuals that illustrate the intricate links among shell morphogenesis, developmental plasticity and phylogeny.

show abstract

Section: Morphogenesis Of Lateral Ribs and Spinesmentioning

confidence: 99%

Section: Morphogenesis Of Lateral Ribs and Spinesmentioning

confidence: 99%

Section: Morphogenesis Of Lateral Ribs and Spinesmentioning

confidence: 99%

See 1 more Smart Citation

Learning from beautiful monsters: phylogenetic and morphogenetic implications of left-right asymmetry in ammonoid shells

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Much remains unknown about how shell sculpture develops and functions. Although sculptural expression must be under strong genetic control, there are still only a few studies linking it with specific genes and enzymes (e.g., Webster & Palmer, 2018). Forces generated by the shell‐builder or imposed by the environment affect the flexible mantle edge and the muscular mantle and therefore influence the type and expression of sculpture as the periostracum and then calcium carbonate is added at the shell's growing margin.…”

Section: Introductionmentioning

confidence: 99%

Imbricated shell sculpture in benthic bivalves

Vermeij

Thomson

2023

Journal of Morphology

View full text Add to dashboard Cite

Molluscan shells display a high diversity of external sculpture. Sculptural elements may be symmetrical, where both edges of an element are morphologically similar, or asymmetrical, where one edge is steeper than the other. Asymmetrical sculpture can be ratcheted, with the leading edges (those in the direction of locomotion or growth) less steep than the trailing edges, or imbricated (leading edges steeper than trailing edges). While the ratcheted sculpture is better known, the diversity of imbricated sculpture has remained largely unexplored. In a survey of extant benthic shellbearing molluscs, we document imbricated sculpture primarily in epifaunal bivalves or on the exposed sectors of shells of semi-infaunal bivalves. Imbricated sculpture is particularly widespread in pteriomorphian bivalves, but it is absent in the subclade Mytiloidea as well as in highly mobile Pectinidae. It also occurs in many carditid bivalves (Archiheterodonta) and in phylogenetically scattered euheterodonts. In several infaunal bivalves including species of Cardites (Carditidae), Hecuba (Donacidae), and Chione (Veneridae), comarginal elements on the posterior sector are imbricated whereas anterior comarginal ridges are ratcheted. Imbricated sculpture in bivalves tends to be concentrated on the upper (left) valves of pectinids or on the posterior sector of both valves in archiheterodonts and euheterodonts.Imbricated sculpture is uncommon in gastropods, even in epifaunal species, but does occur in the collabral ridges in some Vasidae and a few other groups. Expression of imbricated sculpture does not depend on shell mineral composition or microstructure. The ecological distribution and within-shell pattern of expression of imbricated sculpture point to the likelihood that this type of asymmetrical sculpture is both widespread and potentially functional. Additionally, we present a potential methodology whereby shell sculpture categories (symmetrical, ratcheted, and imbricated) may be quantified by comparing the lengths of corresponding leading and trailing edges across the shell surface.

show abstract

“…Such models have expanded beyond the reaction–diffusion systems of Meinhardt (Meinhardt, , , Meinhardt & Klingler, ) to include neurosecretory models (Boettiger, Ermentrout, & Oster, ; Ermentrout, Campbell, & Oster, ; Saleuddin & Kunigelis, ) and the “road‐holding” hypothesis, which posits that shell growth is guided by spatial feedback from shell previously deposited one revolution earlier (Hammer & Bucher, ; Hutchinson, ). Although the growth of shell sculpture has been observed in many taxa (Berry, ; Gostan, ; Illert, ; Inaba, ; Laxton, ; Liew, Kok, Schilthuizen, & Urdy, ; MacGinitie & MacGinitie, ; Spight, Birkeland, & Lyons, ; Spight & Lyons, ), experimental studies of how different types of sculpture are produced are rare (Checa & Jiménez‐Jiménez, ; Checa, Jiménez‐Jiménez, & Rivas, ; Webster & Palmer, , ). Yet to distinguish among various models of sculpture growth, experimental studies are essential.…”

Section: Introductionmentioning

confidence: 99%

How do gastropods grow synchronized shell sculpture? Effect of experimental varix manipulations on shell growth byCeratostoma foliatum(Muricidae: Ocenebrinae)

Webster

Palmer

2019

Invertebrate Biology

Self Cite

View full text Add to dashboard Cite

Gastropod shells display striking patterns in both color and sculpture, but rather little is known about the developmental mechanisms that produce those patterns. Here, we tested a physical feedback hypothesis for how snails control spatial patterning of shell sculpture. Varices—a form of synchronized, blade‐like axial sculpture—are produced at regular intervals around the shell and often aligned closely between adjacent whorls. Older varices were believed to provide a spatial cue about where to position a new varix. To test this hypothesis, we manipulated physical cues by cutting off varices or attaching new ones to the body whorl of individuals of Ceratostoma foliatum, and then allowing snails to grow a new varix. We found that previous varices on the shell were neither necessary nor sufficient to induce a new varix at a particular location. However, the position of older varices did appear to affect the fine tuning of subsequent varix placement. The results of our experiments therefore suggest that varix synchrony arises mainly from some internal mechanism that yields a standardized amount of spiral growth per growth spurt. We also found that shell damage can induce varix production in unusual or aberrant locations during subsequent shell growth.

show abstract

Connecting pattern to process: Growth of spiral shell sculpture in the gastropod Nucella ostrina (Muricidae: Ocenebrinae)

Cited by 5 publications

References 34 publications

Learning from beautiful monsters: phylogenetic and morphogenetic implications of left-right asymmetry in ammonoid shells

Learning from beautiful monsters: phylogenetic and morphogenetic implications of left-right asymmetry in ammonoid shells

Imbricated shell sculpture in benthic bivalves

How do gastropods grow synchronized shell sculpture? Effect of experimental varix manipulations on shell growth byCeratostoma foliatum(Muricidae: Ocenebrinae)

Contact Info

Product

Resources

About