Moulting, ontogeny and sexual dimorphism in the Cambrian ptychopariid trilobite Strenuaeva inflata from the northern Swedish Caledonides
(2011) In Palaeontology 54. p.685-703- Abstract
- Three thousand seven hundred disarticulated remains together with several articulated specimens of the Cambrian Series 2 ptychopariid trilobite Strenuaeva inflata Ahlberg and Bergstrom, 1978 have been collected from the Tornetrask area, northern Sweden. The material provides significant new data on the morphology, ontogeny, moulting and enrolment of the species. Two distinct morphotypes, possibly an expression of sexual dimorphism, are recognized. The morph with a pair of bulbs in the frontal area, interpreted as brood pouches, is considered to represent females. Statistical treatment of the length/width ratio in cranidia reveals isometric growth during ontogeny for both morphotypes. The transition from the meraspid to holaspid ontogenetic... (More)
- Three thousand seven hundred disarticulated remains together with several articulated specimens of the Cambrian Series 2 ptychopariid trilobite Strenuaeva inflata Ahlberg and Bergstrom, 1978 have been collected from the Tornetrask area, northern Sweden. The material provides significant new data on the morphology, ontogeny, moulting and enrolment of the species. Two distinct morphotypes, possibly an expression of sexual dimorphism, are recognized. The morph with a pair of bulbs in the frontal area, interpreted as brood pouches, is considered to represent females. Statistical treatment of the length/width ratio in cranidia reveals isometric growth during ontogeny for both morphotypes. The transition from the meraspid to holaspid ontogenetic period has been established through recognition of the successive development of the number of thoracic segments in articulated late meraspides. Throughout its life cycle, S. inflata went through 11 meraspid degrees and at least 17 holaspid growth stages. Inferred moult ensembles and exuviae reveal the successive opening of cephalic sutures and the function of the rostral plate during exuviation. As in other ellipsocephalid trilobites in which enrolment is known, the pygidium and two or three thoracic segments of S. inflata are concealed beneath the cephalon (spiral enrolment) during complete enrolment. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1986690
- author
- Cederstrom, Peter ; Ahlberg, Per LU ; Nilsson, Carin H. ; Ahlgren, John and Eriksson, Mats LU
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- ptychopariid trilobite, Strenuaeva inflata, dimorphism, enrolment, functional morphology, ontogeny, lower Cambrian, Sweden
- in
- Palaeontology
- volume
- 54
- pages
- 685 - 703
- publisher
- Wiley-Blackwell
- external identifiers
-
- wos:000290590000012
- scopus:79956038515
- ISSN
- 1475-4983
- DOI
- 10.1111/j.1475-4983.2010.01021.x
- language
- English
- LU publication?
- yes
- id
- 76af34a2-0790-4eca-9b7e-7969224b2e8d (old id 1986690)
- date added to LUP
- 2016-04-01 11:07:28
- date last changed
- 2022-02-25 08:43:42
@article{76af34a2-0790-4eca-9b7e-7969224b2e8d, abstract = {{Three thousand seven hundred disarticulated remains together with several articulated specimens of the Cambrian Series 2 ptychopariid trilobite Strenuaeva inflata Ahlberg and Bergstrom, 1978 have been collected from the Tornetrask area, northern Sweden. The material provides significant new data on the morphology, ontogeny, moulting and enrolment of the species. Two distinct morphotypes, possibly an expression of sexual dimorphism, are recognized. The morph with a pair of bulbs in the frontal area, interpreted as brood pouches, is considered to represent females. Statistical treatment of the length/width ratio in cranidia reveals isometric growth during ontogeny for both morphotypes. The transition from the meraspid to holaspid ontogenetic period has been established through recognition of the successive development of the number of thoracic segments in articulated late meraspides. Throughout its life cycle, S. inflata went through 11 meraspid degrees and at least 17 holaspid growth stages. Inferred moult ensembles and exuviae reveal the successive opening of cephalic sutures and the function of the rostral plate during exuviation. As in other ellipsocephalid trilobites in which enrolment is known, the pygidium and two or three thoracic segments of S. inflata are concealed beneath the cephalon (spiral enrolment) during complete enrolment.}}, author = {{Cederstrom, Peter and Ahlberg, Per and Nilsson, Carin H. and Ahlgren, John and Eriksson, Mats}}, issn = {{1475-4983}}, keywords = {{ptychopariid trilobite; Strenuaeva inflata; dimorphism; enrolment; functional morphology; ontogeny; lower Cambrian; Sweden}}, language = {{eng}}, pages = {{685--703}}, publisher = {{Wiley-Blackwell}}, series = {{Palaeontology}}, title = {{Moulting, ontogeny and sexual dimorphism in the Cambrian ptychopariid trilobite Strenuaeva inflata from the northern Swedish Caledonides}}, url = {{http://dx.doi.org/10.1111/j.1475-4983.2010.01021.x}}, doi = {{10.1111/j.1475-4983.2010.01021.x}}, volume = {{54}}, year = {{2011}}, }