, Volume 131, Issue 4, pp 293–301 | Cite as

Revisiting a medical case of “stinging” in the human oral cavity caused by ingestion of raw squid (Cephalopoda: Teuthida): new data on the functioning of squid’s spermatophores

  • José Eduardo A. R. MarianEmail author
  • Yukihiro Shiraki
  • Kumi Kawai
  • Sawako Kojima
  • Yasuhiko Suzuki
  • Kenzo Ono
Original Paper


Male squid produce intricate spermatophores that, when transferred to the female, undergo the spermatophoric reaction, a complex process of evagination that leads to the attachment of the spermatangium, that is, the everted spermatophore containing the sperm mass. While this process is still not completely understood, the medical literature includes several reports of “oral stinging” (i.e., punctured wounds in the human oral cavity) following consumption of raw male squid, which contains undischarged spermatophores able to inflict such wounds. Here, we revisit a recent medical report of oral stinging by Shiraki et al. (Pathol Int 61:749–751, 2011), providing an in-depth reanalysis of their histological biopsies and revealing vital information on the functioning of squid spermatophores. The morphology of the spermatangia attached within the oral cavity is similar to the condition found in spermatangia naturally attached to female squids. The spermatangia were able to superficially puncture the superficial layers of the oral stratified squamous epithelium, and numerous, minute stellate particles from the squid spermatophore were found adhered to the oral epithelium. These findings corroborate previous hypotheses on the functioning of squid spermatophores, namely that spermatophore attachment generally involves tissue scarification, and that stellate particles play a vital role in the attachment process. Moreover, spermatophore attachment is confirmed to be autonomous (i.e., performed by the spermatophore itself) in another squid species (possibly a loliginid), and the results strongly indicate that the attachment mechanism is not dependent upon a specialized epithelium, nor a mate’s specific chemical stimulus. From the pathological point of view, the best prophylactic measure at present is the removal of the internal organs of the raw squid prior to its consumption.


Cephalopods Spermatophore Functional morphology Spermatophoric reaction Sperm transfer mechanisms Oral pathology 



JEARM was supported by a postdoctoral fellowship from CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior). The comments of two anonymous reviewers improved the manuscript and are greatly appreciated.


  1. Arkhipkin AI, Laptikhovsky VV (2011) Observation of penis elongation in Onykia ingens: implications for spermatophore transfer in deep-water squid. J Molluscan Stud 76:299–300Google Scholar
  2. Drew GA (1911) Sexual activities of the squid, Loligo pealii. I. Copulation, egg-laying and fertilization. J Morphol 22:327–359CrossRefGoogle Scholar
  3. Drew GA (1919) Sexual activities of the squid Loligo pealii (Les.). II. The spermatophore; its structure, ejaculation and formation. J Morphol 32:379–435CrossRefGoogle Scholar
  4. Hamada A, Watanabe N, Yamazaki Y, Yoshiba S, Kobayashi A (1990) A case of punctured wounds in the oral cavity by sperm-bags of squid. Med Entomol Zool 41:279–280 (in Japanese; abstract in English)Google Scholar
  5. Hess SC (1987) Comparative morphology, variability, and systematic applications of cephalopod spermatophores (Teuthoidea and Vampyromorpha). University of Miami, DissertationGoogle Scholar
  6. Hoving HJT, Laptikhovsky V (2007) Getting under the skin: autonomous implantation of squid spermatophores. Biol Bull 212:177–179PubMedCrossRefGoogle Scholar
  7. Hoving HJT, Nauwelaerts S, Van Genne B, Stamhuis EJ, Zumholz K (2009) Spermatophore implantation in Rossia moelleri Steenstrup, 1856 (Sepiolidae; Cephalopoda). J Exp Mar Biol Ecol 372:75–81CrossRefGoogle Scholar
  8. Jereb P, Vecchione M, Roper CFE (2010) Family Loliginidae. In: Jereb P, Roper CFE (eds) Cephalopods of the world. An annotated and illustrated catalogue of species known to date, vol 2: Myopsid and Oegopsid Squids. FAO Species Catalogue for Fishery Purposes, No. 4. FAO, Rome, pp 38–117Google Scholar
  9. Kawada K, Kawahara M, Akimori T, Yamaguchi T, Okamoto Y, Ishikawa Y (2008) A case of oral stings by spermatophores of Todarodes pacificus. Jpn J Oral Surg 54:423–426 (in Japanese; abstract in English)Google Scholar
  10. Kawamoto F, Iwata T, Ichihara A, Kumada N, Kano R (1990) A case-report of oral-stings by spermatophores of a squid, Tadorodes pacificus Steenstrup. Jpn J Sanit Zool 41:117–119 (in Japanese; abstract in English)Google Scholar
  11. Marian JEAR (2011) Perforating potential of loliginid spermatophores. J Molluscan Stud 77:98–100CrossRefGoogle Scholar
  12. Marian JEAR (2012a) Spermatophoric reaction reappraised: novel insights into the functioning of the loliginid spermatophore based on Doryteuthis plei (Mollusca: Cephalopoda). J Morphol 273:248–278PubMedCrossRefGoogle Scholar
  13. Marian JEAR (2012b) A model to explain spermatophore implantation in cephalopods (Mollusca: Cephalopoda) and a discussion on its evolutionary origins and significance. Biol J Linn Soc 105:711–726CrossRefGoogle Scholar
  14. Marian JEAR, Domaneschi O (2011) Unraveling the structure of squids’ spermatophores: a combined approach based on Doryteuthis plei (Blainville, 1823) (Cephalopoda: Loliginidae). Acta Zool. doi: 10.1111/j.1463-6395.2011.00503.x Google Scholar
  15. Nagakura K, Nakano M, Kanamaru M (1992) Two cases of oral-stings by sperm bag of squid. Tokai J Exp Clin Med 17:195–197PubMedGoogle Scholar
  16. Nakashima H, Akagi M, Miyabe S, Iwasawa H (1996) Two unusual cases of a foreign body in the oral cavity caused by eating raw squid. Acta Otolaryngol Suppl 522:104–107PubMedGoogle Scholar
  17. Nesis KN (1995) Mating, spawning and death in oceanic cephalopods: a review. Ruthenica 6:23–64Google Scholar
  18. Park G-M, Kim J-Y, Kim J-H, Huh J-K (2011) Penetration of the oral mucosa by parasite-like sperm bags of squid: a case report in a Korean woman. J Parasitol 98:222–223PubMedCrossRefGoogle Scholar
  19. Roper CFE, Nigmatullin C, Jereb P (2010) Family Ommastrephidae. In: Jereb P, Roper CFE (eds) Cephalopods of the world. An annotated and illustrated catalogue of species known to date, vol 2: Myopsid and Oegopsid Squids. FAO Species Catalogue for Fishery Purposes, No. 4. FAO, Rome, pp 269–347Google Scholar
  20. Shiraki Y, Kawai K, Kojima S, Suzuki Y, Ono K (2011) Stinging in the oral cavity caused by ingestion of the sperm bags of a squid: a case report. Pathol Int 61:749–751PubMedCrossRefGoogle Scholar
  21. Takahama H, Kinoshita T, Sato M, Sasaki F (1991) Fine structure of the spermatophores and their ejaculated forms, sperm reservoirs, of the Japanese common squid, Todarodes pacificus. J Morphol 207:241–251CrossRefGoogle Scholar
  22. Takai K, Nakajima H, Hanaguri M, Kanda T (1989) A case of stinging in the upper gastrointestinal tract by eating raw squids. Jpn J Sanit Zool 40:227 (in Japanese)Google Scholar

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • José Eduardo A. R. Marian
    • 1
    Email author
  • Yukihiro Shiraki
    • 2
  • Kumi Kawai
    • 3
  • Sawako Kojima
    • 4
  • Yasuhiko Suzuki
    • 2
  • Kenzo Ono
    • 2
  1. 1.Departamento de ZoologiaInstituto de Biociências da Universidade de São PauloSão PauloBrazil
  2. 2.Department of PathologyTosei General HospitalSeto CityJapan
  3. 3.Department of PathologyAichi Medical UniversityNagakute CityJapan
  4. 4.Department of OtolaryngologyTosei General HospitalSeto CityJapan

Personalised recommendations