Organisms Diversity & Evolution

, Volume 17, Issue 1, pp 121–135 | Cite as

Comparative study of bisected proboscides of Pycnogonida

  • Philipp Wagner
  • Jana S. Dömel
  • Michaela Hofmann
  • Jeremy Hübner
  • Florian Leese
  • Roland R. MelzerEmail author
Original Article


To comparatively describe “inner” pharynx armatures in pycnogonids, we bisected proboscides of Achelia langi (Dohrn, 1881), Anoplodactylus californicus Hall, 1912, Ascorhynchus castellioides Stock, 1957, Austrodecus glaciale Hodgson, 1907, Callipallene margarita (Gordon, 1932), Colossendeis macerrima Wilson, 1881, Endeis spinosa (Montagu, 1808), Nymphon macronyx Sars, 1877, Pallenopsis patagonica (Hoek, 1881), Pantopipetta sp., Pigrogromitus timsanus Calman, 1927, and Pycnogonum litorale (Strøm, 1762) and analyzed them with the scanning electron microscope (SEM). Moreover, proboscides were stained with actin green to visualize the muscle arrangement with fluorescence and confocal microscopes (A. langi) and were analyzed with microcomputed X-ray tomography (μCT; Ascorhynchus japonicus). As a result of our observations, sets of characters that vary between taxa are established. These traits include length and width of proboscis, shape and structure of the inner mouth opening, borders and armature of the antimeres, shape and position of denticle arrays and rows, relative length of pharyngeal filter apparatus, and arrangement and structure of the filter bristles. Analyses of these characters indicate a substantial variability on the pantopod’s proboscis inner surface probably as an adaptation to different food sources. Finally, we suggest that the presence of the oyster basket represents a ground pattern character of Pycnogonida.


Pharynx Comparative morphology Scanning electron microscopy Sea spider 



This study was partly supported by German Research Foundation grant Me 2683/8 and Le 2323/3 within Priority Programme 1158 (“Antarctic Research“) and by grant of Sea Life Center Munich to R. Melzer. Special thanks go to “Martl” Heß for piloting the confocal microscope.


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Copyright information

© Gesellschaft für Biologische Systematik 2016

Authors and Affiliations

  • Philipp Wagner
    • 1
    • 2
  • Jana S. Dömel
    • 3
  • Michaela Hofmann
    • 1
    • 2
  • Jeremy Hübner
    • 1
    • 2
  • Florian Leese
    • 3
  • Roland R. Melzer
    • 1
    • 2
    • 4
    Email author
  1. 1.Biocenter, Department Biologie IILudwig-Maximilians-Universität MünchenPlanegg-MartinsriedGermany
  2. 2.Zoologische StaatssammlungMunichGermany
  3. 3.Fakultät für Biologie, Aquatische ÖkosystemforschungUniversität Duisburg-EssenEssenGermany
  4. 4.Geobio Center LMUMunichGermany

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