Editing Hectocotylus (section)

==Variability==
Hectocotyli are shaped in many distinctive ways, and vary considerably between species. The shape of the tip of the hectocotylus has been much used in [[octopus]] [[systematics]].

* Many [[Coleoidea|coleoids]] lack hectocotyli altogether.<ref name=ToL /> 
* Among [[Decapodiformes]] (ten-limbed cephalopods), generally either one or both of arms IV are hectocotylized.
* In [[Incirrina|incirrate]] octopuses, it is one of arm pair III.<ref name=ToL>Young, R.E., M. Vecchione & K.M. Mangold (1999). [http://tolweb.org/accessory/Cephalopoda_Glossary?acc_id=587 Cephalopoda Glossary]. [[Tree of Life Web Project]].</ref> Rare examples of double and bilateral hectocotylization have also been recorded in incirrate octopuses.<ref>Robson, G.C. 1929. On a case of bilateral hectocotylization in ''Octopus rugosus''. ''Journal of Zoology'' '''99'''(1): 95–97. {{doi|10.1111/j.1469-7998.1929.tb07690.x}}</ref><ref>Palacio, F.J. 1973. {{cite web|url= https://archive.org/details/nautilus87amer |title=On the double hectocotylization of octopods. |year=1973 |publisher=Melbourne, Fla., etc., American Malacologists, inc., etc. }} ''The Nautilus'' '''87''': 99–102.</ref>
* In male [[seven-arm octopus]]es (''Haliphron atlanticus''), the hectocotylus develops in an inconspicuous sac in front of the right eye that gives the male the appearance of having only seven arms.
* In [[Argonaut (animal)|argonauts]], the male transfers the spermatophores to the female by putting its hectocotylus into a cavity in the [[mantle (mollusc)|mantle]] of the female, called the ''pallial cavity''. This is the only contact the male and female have with each other during [[copulation (zoology)|copulation]], and it can be at a distance. During copulation, the hectocotylus breaks off from the male. The [[funnel–mantle locking apparatus]] on the hectocotylus keeps it lodged in the pallial cavity of the female.

===Table of hectocotyli===
{| class="wikitable"
!width= | Illustration
!width= | Species
!width= | Family
|-
| [[File:Abraliopsis morisi hectocotylus-English.jpg|250px<!--upright image, to equalize image sizes-->]]
| ''[[Abraliopsis morisi]]''
| [[Enoploteuthidae]]
|-
| [[File:Argonauta bottgeri hectocotylus-2.jpg|300px]]
| ''[[Argonauta bottgeri]]''
| [[Argonautidae]]
<!--|-
| [[File:Hectocotyle1-2.jpg|300px]]
| ?
| ?-->
|-
| [[File:Bathypolypus arcticus hectocotylus-2.jpg|300px]]
| ''[[Bathypolypus arcticus]]''
| [[Octopodidae]]
|-
| [[File:Graneledone verrucosa hectocotylus.jpg|300px]]
| ''[[Graneledone verrucosa]]''
| [[Octopodidae]]
|-
| [[File:Haliphron atlanticus hectocotylus.jpg|300px]]
| ''[[Haliphron atlanticus]]''
| [[Alloposidae]]
|-
|[[File:Ocythoe tuberculata hectocotylus.jpg|300px]]
| ''[[Ocythoe tuberculata]]''
| [[Ocythoidae]]
|-
| [[File:Scaeurgus patagiatus hectocotylus-2.jpg|300px]]
| ''[[Scaeurgus patagiatus]]''
| [[Octopodidae]]
|-
| [[File:Tremoctopus violaceus5.jpg|200px<!--upright image, to equalize image sizes-->]]
| ''[[Tremoctopus violaceus]]''
| [[Tremoctopodidae]]
|-
| [[File:Uroteuthis duvauceli hectocotylus.jpg|300px]]
| ''[[Uroteuthis duvauceli]]''
| [[Loliginidae]]
|}