Arm anomalies: cases of supernumerary development and bilateral agenesis of arm pairs in Octopoda (Mollusca, Cephalopoda)

  title={Arm anomalies: cases of supernumerary development and bilateral agenesis of arm pairs in Octopoda (Mollusca, Cephalopoda)},
  author={Ronald B. Toll and Lynetta C. Binger},
SummaryThe first case of true hexapody among the Octopoda, resulting from bilateral agenesis of one arm pair, is described for a malePteroctopus tetracirrhus. A case of decapody, with uniform development of all arms, is also reported for the first time for a maleOctopus briareus. Both conditions apparently result from developmental anomalies of the embryonic arm anlagen. A survey of other anomalous conditions relating to arm development and regeneration within the Cephalopoda is provided. A… 

First observation of a double tentacle bifurcation in cephalopods

A female with the two tentacles bifurcated was found within a sample of 54 specimens of Moroteuthis ingens collected by a Spanish trawler fishing in the South Atlantic around the Falklands Islands

A Unique Case of Bilateral Hectocotylization in the North Pacific Giant Octopus (Enteroctopus dofleini)

In over one hundred years of research, double hectocotylization has been reported in only six individual cases in six different species of octopus including: Eledone cirrhosa (by Appellof, 1892),Octopus briareus (by Robson, 1929), Octopus vulgaris (by Palacio, 1973, Octopus selene ( by Palacio) and Octopus minor (by Higashide et al., 2007).

The Musculature of Coleoid Cephalopod Arms and Tentacles

  • W. Kier
  • Biology
    Front. Cell Dev. Biol.
  • 2016
It is likely that coleoid cephalopods use ultrastructural modifications rather than tissue-specific myosin isoforms to tune contraction velocities.

Arm Abnormality in Octopus hubbsorum (Mollusca: Cephalopoda: Octopodidae)

This is the principal target species in the octopus fisheries in Mexico, and a female with abnormally bifurcated second arm was collected from an artisanal fishery in Puerto Angel, Oaxaca.

Variability in Sepietta oweniana (Cephalopoda: Sepiolidae) hectocotyli

The morphological variability observed in hectocotyli of Sepietta oweniana specimens caught in the Sardinian seas is reported and measured and atypical variants from the normal hectOCotylus are described and illustrated.

Potentially handicapped but otherwise functional: Malformations in prey capture tools show no impacts on octopus life

Surprisingly, the teratological condition of the individual likely had no severe impacts on its life, even though it likely represents a handicap for its survival during its planktonic life.

Flapjack devilfish in the northern North Atlantic: morphology, biology and ecology of Opisthoteuthis borealis (Cephalopoda, Octopoda, Cirrata)

Despite the assumption that Cirrata feed on relatively small prey only, large mature males of O. borealis consume polychaetes reaching 41.5–45.9% ML of the specimens, suggesting well-developed regeneration is present even in this ancient taxon of cephalopods.

Handbook of Pathogens and Diseases in Cephalopods

This work has been designed as a short, easy to follow ‘handbook,’ with the aim of presenting fundamental aspects of the anatomical and histological structures as well as the identification of different pathogens, the resulting histopathology, and the diagnosis of diseases in cephalopods.

Regeneration and Healing

Although they often get resolved autonomously, the early identification and monitoring of post-traumatic events is fundamental in the context of animal welfare.



Pattern Regulation in the Regenerating Limbs of Urodele Amphibians

The purpose of this paper is to review the experiments that have been published since the turn of the century that deal with patter formation in the regenerating limbs of urodele amphibians and to discuss these results in the context of recent theoretical models.

Arm Abnormality in Octopus

An unusual feature was the presence of a well-developed web between the two divisions as found uniting the bases of normal arms in this species of cephalopod.

LXXIV.—Notes on the Cephalopoda.—IX. Remarks on Atlantic Octopoda &c. in the Zoölogisch Museum, Amsterdam

(1929). LXXIV.—Notes on the Cephalopoda.—IX. Remarks on Atlantic Octopoda &c. in the Zoologisch Museum, Amsterdam. Annals and Magazine of Natural History: Vol. 3, No. 18, pp. 609-618.

Über den gespaltenen Arm eines Octopus vulgaris

  • B. Hankó
  • Biology
    Archiv für Entwicklungsmechanik der Organismen
  • 2005
Doppeland Spaltbildungen wurden bereits aus dem ganzen Tierreiehe beschrieben, oder das Hervorsprossen eines kleineren seitlichen Saugnapfes aus einem grSl~eren, bei den Cephalopoden zu sein.

Cephalopoda Tintenfische

  • Morphogenese der Tiere. Gustav Fischer, Stuttgart,
  • 1978