How to find out squid (Histioteuthis) gender?

Nov 7, 2009
Hi all,
I'm researching on HISTIOTEUTHIS species for beak morphometry on different life stages, and I would like to differentiate between MALES and FEMALES.
I have extracted the mantle cavity organs, including the stomach, glands, and weird white and pink organs I recognise as the GONADS.
BUT I find it difficult to see if they are male or female. I've seen some general diagrams for cephalopods, but I dont recognise such structures in Histioteuthis.
Can anyone give me any tip, diagram, photography to show me the generic difference in squid gonads please?

PD. Its quite of an urge, I'm presenting the seminar in 2 weeks and I have to process +60 gonads :S
PDD. If in addition to this someone could give me a clue on visual recognition of sexual maturity, it would be great!
Thank you.


Staff member
Nov 19, 2002
Mature males of Histioteuthis have hectocotylised arms, so it should be possible to tell from external morphology (before removing the viscera) which sex you are dealing with. Once the mantle is open (ventral dissection), you will also see that the viscera are either (in females) symmetrical across the midline, with two nidamental glands, or (in males) asymmetrical, with a large whitish mass posteriorly along the left side (testis and Needham's sac) and the terminal organ protruding (see photo here: -- the terminal organ, lying along the pink digestive gland, has many small spermatophores visible within it).

Hope that helps!