Feeding in Myriapoda and Onychophora

[Archilegt]

I am opening this issue so that I can develop the topic of "Feeding in Myriapoda and Onychophora" here.
Status: In progress. Add data on Symphyla and additional Chilopoda.
Open to commenting: No, not until the status is changed to "Done".
Last updated: 7.ii.2023

Useful links
Soil Food Web Ontology in AgroPortal
List of feeding behaviours

Text will be added here

Chilopoda

• Fluid-feeding with a pharyngeal pump with a double-anchor cross section: Present in order Geophilomorpha (Chilopoda) (31, 32) (Manton, 1965; Koch & Edgecombe, 2012). Syn. suctorial feeding, from suctorial feeder, sourced from Lawrence (1953), cited by Lewis (1961: 243).

Newport (1843: 181) described the genus Gonibregmatus (Chilopoda: Geophilomorpha) as having mouthparts modified for sucking. Cook (1896: 66) somehow missed Newport's morphological description of the mouthparts and stated "mouth parts unknown" in the diagnosis of his new family Gonibregmatidae. Pocock (1898: 59-60) confirmed Newport's statement on "the mouth as adapted for sucking" in the genus Gonibregmatus, as the mandibles are notably different from other centipedes and "the mandibles, labium and labrum form a kind of proboscis along which the fluid tissues of prey flow or are sucked backwards to the mouth".

There seems to be a gap between the pioneer research cited above and the one that is cited next. Lawrence (1953), observing the narrow oesophagus and small mouthparts of geophilomorphs, suggested that they might be suctorial feeders. A suggestion of "extra-intestinal digestion" was made by Blower (1957: 560). A feeding event was described by Lewis (1961: 243), who observed prey internal tissue maceration with the forcipules and supposed the expulsion of digestive fluids and the sucking in of the liquid products of digestion. Koch et al. (2011: 122) summarized the previous observations as "extra-intestinal liquefaction of prey within the prey’s body".

References:

• Blower JG (1957): Feeding habits of a marine centipede. Nature, 180: 560. https://doi.org/10.1038/180560a0
• Cook, O. F. (1896d): An arrangement of the Geophilidæ, a family of Chilopoda. Proceedings of the United States National Museum, 18 (1039): 63-75. https://doi.org/10.5479/si.00963801.18-1039.63
• Koch M, Müller CHG, Hilken G, Rosenberg J (2011): Chapter 6 Chilopoda – Digestive System. Pp. 121-136. In: Minelli, A. (Ed.). Treatise on Zoology - Anatomy, Taxonomy, Biology. The Myriapoda, Volume 1. Leiden, The Netherlands: Brill. https://doi.org/10.1163/9789004188266_007
• Lawrence RF (1953): The biology of the cryptic fauna of forests with special reference to the indigenous forests of South Africa. Cape Town.
• Lewis JGE (1961): The life history and ecology of the littoral centipede Strigamia (=Scolioplanes) maritima (Leach). Proceedings of the Zoological Society of London, 137: 221-247. https://doi.org/10.1111/j.1469-7998.1961.tb05900.x
• Newport, G. (1843): On some new genera of the class Myriapoda. Proceedings of the Zoological Society of London, 10 (119): 177-181. https://www.biodiversitylibrary.org/part/244439
• Pocock, R. I. (1898): Report on the centipedes and millipedes obtained by Dr. A. Willey in the Loyalty Islands, New Britain, and elsewhere. Pp. 59-74 + pl. 6. https://www.biodiversitylibrary.org/page/43057548 In: Willey, A. (Ed.). Zoological Results based on material from New Britain, New Guinea, Loyalty Isles and elsewhere, collected during the years 1895, 1896 and 1897. Part 1. University Press, Cambridge, 120 pp. + 11 pls. https://doi.org/10.5962/bhl.title.69286

"A predominantly suctorial feeding based on a more intense extra-intestinal liquefaction of prey within the prey’s body is assumed for Craterostigmus and geophilomorph centipedes (e.g., Blower, 1957; Lewis, 1961; Manton, 1965)." See Koch et al. (2011: 122).

• Manton SM (1965): The evolution of arthropod locomotory mechanisms. Part 8. Functional requirements and body design in Chilopoda, together with a comparative account of their skeletomuscular systems and an appendix on a comparison between burrowing forces of annelids and chilopods and its bearing upon the evolution of the arthropodan haemocoel. Journal of the Linnean Society (Zoology), 46: 251-483.

• Koch M., Edgecombe G. D. (2012). The preoral chamber in geophilomorph centipedes: Comparative morphology, phylogeny, and the evolution of centipede feeding structures. Zool. J. Linn. Soc. 165, 1–62.

• Herbivory: Brade-Birks (1929) in his review of feeding in centipedes concluded that the normally carnivorous geophilomorphs might sometimes take plant food. However, no evidence of a herbivorous diet was found in the non-specific carnivore Strigamia maritima by Lewis (1961: 243).
  Brade-Birks, S. Graham (1929): Notes on Myriapoda 33. The economic Status of Diplopoda and Chilopoda and their allies. Part I. Journal of the South-Eastern Agricultural College, Wye, Kent 26: 178-216.

Symphyla

Biting-chewing feeding type. Mandibles with a strong mandibular musculature.

Manton, S. M. & Harding, J. P. (1964). "Mandibular mechanisms and the evolution of arthropods." Philosophical Transactions of the Royal Society London B 247: 1-183.
Szucsich, N. U., Pennerstorfer, M. & Wirkner, C. S. (2011). "The mouthparts of Scutigerella immaculata: Correspondences and variation among serially homologous head appendages." Arthropod Structure & Development 40(2): 105-121.

Generally little is known about feeding.
Predation: At least Symphylella seems to be partly predatory on soil arthropods and nematodes.
Walter, D. E. & Ikonen, E. K. (1989). "Species guilds and functional groups: taxonomy and behaviour in nematophagous arthropods." Journal of Nematology 21(3): 315-327.
Fungivory: The pest species maybe mainly feed on mycorhizae.

Pauropoda

• Fluid-feeding by peristaltic contraction of the gut: Reported for class Pauropoda (5) (Hüther, 1959).
  Revise contrasting information:
  Starling, J. H. (1944). "Ecological studies of the Pauropoda of the Duke Forest." Ecological Monographs 14(3): 291-310.

Acknowledgements (Symphyla, Pauropoda): Dr. Nikolaus Szucsich, Naturhistorisches Museum Wien (pers. comm. and literature suggestions).

Onychophora

• Fluid-feeding with a triradiate sucking pharynx: Present in phylum Onychophora (4) (Nielsen, 2013).

Diplopoda

• Biting-chewing feeding: Typical of millipedes (class Diplopoda), which mainly feed on dead plant material (13) (Manton, 1964).
• Slurping-feeding: Present in order Platydesmida (Diplopoda: Colobognatha) (see 21, 22) (Blanke & Wesener, 2014; Moritz et al., 2021). Transverse moving mouthpart configuration, without a sucking pump. On the basis of the gut content of Platydesmida, fungal hyphae is their main food source (16) (Macias et al., 2019). Platydesmida might even show external digestion (18) (Wong et al., 2020).
• Fluid-feeding with a cephalic sucking pump: Reported for the orders Polyzoniida, Siphonocryptida, and Siphonophorida (Diplopoda: Colobognatha) by Moritz et al. (2022). The most likely movement of the mandibles in the studied millipedes is a protrusion-retraction through the minute functional mouth opening. The mandibles can only be used to penetrate surfaces or to loosen particles by scraping or piercing instead of chewing.

Fluid-feeding was suspected in Colobognatha because of their acuminate heads and the largely reduced or modified mandibles, compared to biting-chewing millipedes (1–3, 14, 15). Colobognatha probably feed on algal films, bacterially degraded substances, or fungal hyphae (16–18).

Taxa	Taxa	Structure of the pumping chamber	Musculature of the pumping chamber	"valves"	Comments	References
Onychophora	-	Triradiate sucking pharynx	Radial and circular muscles	-	Peristaltic movement	(4)
Pauropoda	-	Gut	-	-	Peristaltic contraction	(5)
Chilopoda	Geophilomorpha	Pharynx; X-/pipette-shaped, thickened walls	Lateral dilator muscles; constrictor muscles	-	Structure and function largely unknown	(31, 32)
Diplopoda	Polyzoniida	Preoralchamber/pharynx; floor strong, sclerotized(?) supported by tentorial complex; Roof thin	Dorsal dilator muscles; dorsal compressor muscles	Posterior sphincter muscle	Emptying of pump by compressor muscles	Moritz et al. (2022)
Diplopoda	Siphonocryptida	Preoralchamber/pharynx, floor strong, sclerotized(?) supported by tentorial complex; Roof thin	Dorsal dilator muscles; dorsal compressor muscles	Posterior sphincter muscle	Emptying of pump by compressor muscles	Moritz et al. (2022)
Diplopoda	Siphonophoridae	Preoralchamber/pharynx, floor strong, sclerotized(?) supported by tentorial complex; Roof thin	Dorsal dilator muscles; no compressor muscles	-	Emptying of pump by constrictor muscles	Moritz et al. (2022)
Diplopoda	Siphonorhinidae	Preoralchamber/pharynx, floor strong, sclerotized(?) supported by tentorial complex; Roof thin	Dorsal dilator muscles; no compressor muscles	Posterior sphincter muscle	Emptying of pump by constrictor muscles	Moritz et al. (2022)

[To be continued...]

References
Main reference:

• Moritz L, Borisova E, Hammel JU, Blanke A, and Wesener T. (2022). A previously unknown feeding mode in millipedes and the convergence of fluid feeding across arthropods. Science Advances, 7 (8): eabm0577, 1-9. https://doi.org/10.1126/sciadv.abm0577

References therein:

• [1] O. F. Cook, H. F. Loomis, Millipeds of the order Colobognatha, with descriptions of six new genera and type species, from Arizona and California. Proc. U.S. Natl. Museum 72, 1–26 (1928).
• [2] J. F. Brandt, Ueber saugende Myriapoden (Colobognatha). Isis von Oken 13, 704 (1834).
• [3] S. M. Manton, The evolution of arthropodan locomotory mechanisms. Part 71. Functional requirements and body design in Colobognatha (Diplopoda), together with a comparative account of diplopod burrowing techniques, trunk musculature and segmentation. Zool. J. Linn. Soc. 44, 383–462 (1961).
• [4] Nielsen C. (2013). The triradiate sucking pharynx in animal phylogeny. Invertebr. Biol., 132: 1–13.
• [5] Hüther W. (1959). Zur Ernährung der Pauropoden. Naturwissenschaften, 46 (19): 563–564. https://doi.org/10.1007/BF00631300
• [13] S. M. Manton (1964). Mandibular mechanisms and evolution of arthropods. Philos. Trans. R. Soc. Lond. B Biol. Sci. 247, 1–183.
• [14] R. L. Hoffman, Diplopoda, in Synopsis and Classification of Living Organisms, S. P. Parker, Ed. (McGraw-Hill, 1982), pp. 689–719.
• [15] M. Koch, Diplopoda—General morphology, in Treatise on Zoology - Anatomy, Taxonomy, Biology. The Myriapoda, Volume 2, A. Minell, Ed. (Brill, 2015), pp. 7–67.
• [16] A. M. Macias, P. E. Marek, E. M. Morrissey, M. S. Brewer, D. P. G. Short, C. M. Stauder, K. L. Wickert, M. C. Berger, A. M. Metheny, J. E. Stajich, G. Boyce, R. V. M. Rio, D. G. Panaccione, V. Wong, T. H. Jones, M. T. Kasson (2019). Diversity and function of fungi associated with the fungivorous millipede, Brachycybe lecontii. Fungal Ecol. 41, 187–197.
• [17] H. Hauser, K. Voigtländer, Doppelfüßer (Diplopoda) Deutschlands: Verhalten, Ökologie, Verbreitung, Lebendbestimmung (Deutscher Jugendbund für Naturbeobachtung, 2019).
• [18] V. Wong, D. Hennen, A. Macias, M. Brewer, M. Kasson, P. Marek (2020). Natural history of the social millipede Brachycybe lecontii Wood, 1864. Biodivers. Data J. 8, e50770.
• [21] Blanke A., Wesener T. (2014). Revival of forgotten characters and modern imaging techniques help to produce a robust phylogeny of the Diplopoda (Arthropoda, Myriapoda). Arthropod Struct. Dev. 43, 63–75.
• [22] Moritz, L., Blanke, A., Hammel, J.U. and Wesener, T. (2021). First steps toward suctorial feeding in millipedes: Comparative morphology of the head of the Platydesmida (Diplopoda: Colobognatha). Invertebr. Biol., 140: e12312. https://doi.org/10.1111/ivb.12312
• [31] Manton S. M. (1965). The evolution of arthropodan locomotory mechanisms. Part 8. Functional requirements and body design in Chilopoda, together with a comparative account of their skeleto-muscular systems and an appendix on a comparison between burrowing forces of annelids and chilopods and its bearing upon the evolution of the arthropodan haemocoel. Zool. J. Linn. Soc. 45, 251–484.
• [32] Koch M., Edgecombe G. D. (2012). The preoral chamber in geophilomorph centipedes: Comparative morphology, phylogeny, and the evolution of centipede feeding structures. Zool. J. Linn. Soc. 165, 1–62.