Talk:Hagfish

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WikiProject Echo has identified Hagfish as a foreign language featured article. You may be able to improve this article with information from the German language Wikipedia.

Hagfish are cousins of a close line that died out. They are not in any form fish.

Contents 1 Genetic Analysis 2 Reproduction 3 Dimensions 4 Are they vertebrates or not? 5 Commercial exploitation section 6 Travelling knot 7 Language 8 Venom? 9 Eptatretus minor 10 Heart System

[edit] Genetic Analysis

In this section it is noted that Hagfish slime is unique in that it contains threadlike fibres and yet slug slime also contains threadlike fibres. Is there a significant difference between these two slime fibres? —Preceding unsigned comment added by ElJayDee (talk • contribs) 19:05, 24 March 2008 (UTC)

[edit] Reproduction

Does anyone know how hagfish reproduce? Or if it is not well known, should someone point that out? It would be nice. PhoenixSeraph 20:57, 21 March 2006 (UTC)

They're not hermaphroditic. Male and female hagfish look exactly the same, except for reproductive structures. It's believed that hermaphroditism was acquired very recently in their evolutionary history. I'll fix this point soon. Aelwyn 15:55, 10 September 2006 (UTC)

[edit] Dimensions

What are the dimensions of a hagfish? It is difficult to know from the image.

Also, what does it mean that they 'use a knot' to get out of their feeding places?

I remember reading they tie their bodies into a knot then slide the knot towards the mouth. It then presses on whatever the mouth is attached to, disengaging. I'll add a description.--24.16.72.226 01:22, 17 May 2005 (UTC)

Pacific hagfish are between 20 and 40 cm in length, depending on age.

• There is also no mention of their average diameter range, this should be included. Blue Dinosaur Jr 15:02, 12 June 2007 (UTC)

[edit] Are they vertebrates or not?

This article indicates that they are vertebrates whereas the Chordate article indicates that they are not. There's a clue at the Vertebrate article which seems to imply that whether they are vertebrates or not is a matter of dispute. I wonder whether someone who knows the subject could clarify things so that we could have the most correct information and have it given consistantly. Jimp 06:19, 8 March 2006 (UTC)

As far as I am aware, hagfish are definitely chordates, and I've not seen a clear argument against their being vertebrates. But because they are often regarded as the basal group of vertebrates, it is easy for someone to come along with a new definition of 'Vertebrata' which just happens to leave the hagfish out in the cold. I hold that reference works should err on the conservative side, reflecting consensus not innovation, and list Myxini as the basal group in Vertebrata unless a sound citation for removing them can be found. Myopic Bookworm 14:08, 23 March 2006 (UTC)

As far as I know, there still is debate about hagfish being vertebrates. Here's some recent work on their cartelidge and genetic distance from lampreys that suggests they're not vertebrates, though. [1] and [2].--Estelahe 21:40, 23 March 2006 (UTC)

Actually the anatomical situation is quite clear. Myxioniformes do not have any vertebra, nor do Petromyzontiformes, which only have small cartilage arches to protect the 'upper' part of their neural tube. It depends on what you mean by vertebrate. They have always been included in pylum Chordata, subphylum Vertebrata. The presence of true vertebrae is not peculiar of all Vertebrata, but only of Gnathostomatha. The main real apomorphy in the skeleton of so-called Vertebrata (sensu lato) is the presence of the cranium and thus, according to many Authros, they should be renamed Craniota. The name Vertebrata is nearly always retained only because of its ancient tradition.

• They are part of the subphylum Vertebrata so, taxonomically speaking, they are vertebrates.
• They do not have vertebrae so, anatomically, ther're not vertebrates.

I'll also fix this, unless somebody who's able to write proper english does it for me ;-) Aelwyn 15:55, 10 September 2006 (UTC)

Hagfish aren't vertebrates. I'm taking a course on vertebrate anatomy right now, and hagfish are classfied as Agnathans: a PRE-VERTEBRATE.

As you can see on my user page, I'm studying Natural Sciences in Padua. I had exams of general zoology, compared anatomy and evolutive history of the vertebrates, so I know what I'm talking about, if it's a question about curricula vitæ. Not to seem aggressive, but if you read a little better what I have written, you will notice that I already know they are not anatomically vertebrata. The term Vertebrata is nearly always used to mean the Craniota because of its long tradition, as is in Wikipedia's tassoboxes. If you study vertebrate anatomy, it's quite obvious that Agnathes are not part of the course, which will deal with the skeletons of those animals who do have vertebræ! Please, next time be more careful and kind (you even WRITE THIS UNPLITE WAY!) and sign. Aelwyn 21:53, 20 September 2006 (UTC)

" If you study vertebrate anatomy, it's quite obvious that Agnathes are not part of the course, which will deal with the skeletons of those animals who do have vertebræ! "

Actually, the vast majority of courses on vertebrate anatomy deal with Phylogeny, which includes the development from Agnatha into Vertebrates. I find it strange that you haven't studied them.

I'm a zoology graduate; Agnatha were the subject of the first lecture in my Vertebrates course. If "Agnathes are not part of the course", that just tells you something about the professor who wrote the course, not about the animals. Myopic Bookworm 09:20, 21 September 2006 (UTC)

Well, I think it's not worth starting a flame about where a zoology professor should start his courses. Where I study there is no Vertebrate Anatomy course and as it looked like the guy to whom I answered hadn't studied Agnathans on his own, I thought it was something quite different from mine, which dealt with both anatomy and phylogeny and did inculde Agnathans. The point is: we should make it clear for a non-expert how things are and not have discussions about definitions and about our studies. The article was ambiguous, it looked like we didn't know if Mixiniformes have vertebræ or not, when we all agree it is only a matter of definitons. Now it's better than it was, but it can still be improved very much. Aelwyn 11:36, 21 September 2006 (UTC)

This article needs cleanup and sectioning. I'll try to make everything clear, I just hope 128.189.162.95 does not keep to change the page with his own opinion.

[edit] Commercial exploitation section

Does anyone know the Japanese name for hagfish? How is it fished? How it is prepared? What is the 'eel leather' used for? Are there potential commercial uses for the slime? It'd be nice if someone could expand the information to include a specific section on this.

I am not Japanese. I think very few Chinese people eat this.

Japanese word for hagfish is "メクラウナギ"; "めくらうなぎ" or "盲鰻".

• メクラウナギ (mekuraunagi; in katakana)
• めくらうなぎ (same pronounciation; written in hiragana)
• 盲鰻 (same pronounciation; written in kanji; literally "blind" + "eel")

I know some Japanese people eat lamprey (ヤツメウナギ).

• ヤツメウナギ (yatsumeunagi)
• やつめ‐うなぎ
• 八目鰻 (literally "eight" + "eye" + "eel")

Sometimes, they are known as "七鰓鰻" or "seven" + "gill" + "eel".

In some areas of Japan, costal fishermen use a small boat and a small net to catch lampreys. As far as I know, they may cut the fish into short segments (like chopped sausages) and boil them in water with tofu and some vegetables to make a soup. They may also roast the fish with very thick sauce over charcoal (like roast eel; see unagi).

During the WWII, some people eat the lamprey because it was the only meat they could get. I've never eaten this fish. I saw them eating it once on a Japanese TV show. The reporter said it's very crunchy. Many Japanese people believe lampreys are good for your eyes because of chondroitin sulfate in them. In Edo period, they let nyctalopia patients eat lampreys as a source of Vitamin A. (see: ja:ヤツメウナギ)

I don't know how they cook hagfish. -- Toytoy 13:05, 2 July 2006 (UTC)

I think they use the 'leather' for stuff like wallets, belts etc... —Preceding unsigned comment added by 221.74.145.141 (talk) 13:55, 2 November 2007 (UTC)

i can confirm that they are used for theyr leather, and are not likely eaten, mike roe of dirty jobs just did a show on these, he told us at the end of the segment that they are shipped off to korea and used to make wallets and purses, showing us an example whilst barbecuing a few that he took with him, he tried them and didnt seem to like it as he spat it out after. however the dude behind him that was cooking them didnt seem to mind it thought I'd share:) 24.85.111.11 (talk) 22:03, 23 February 2008 (UTC)bluefoxx

[edit] Travelling knot

I have heard that hagfish can take chunks out of large prey by fastening on with the teeth and then passing a knot from the tail towards the head. This would be worth mentioning if anyone has evidence for it. Myopic Bookworm 11:41, 21 September 2006 (UTC)

It's on my book, with even a picture, so I think it is must be true. I'll tell about it. Aelwyn 12:30, 21 September 2006 (UTC)

And I've seen it on a BBC (I think) documentary about deep sea thingies. They were feeding on a whale carcass. 78.86.166.49 (talk) 22:40, 12 February 2008 (UTC)

[edit] Language

I don't have the time or the expertise to fix this, but the second line of this article refers to the creature's "ass hole". That doens't seem right.

-Holshy —The preceding unsigned comment was added by 206.195.193.254 (talk) 16:37, 27 March 2007 (UTC).

[edit] Venom?

It's not clear to me why a section of this article is entitled "Venom." Apparently hagfish are not venomous, and the contents of the section don't seem to have anything to do with venom. -75.90.166.235 (talk) 07:16, 6 January 2008 (UTC)

[edit] Eptatretus minor

This article currently includes a drawing of Eptatretus minor, which appears to be a hagfish. However the list at Hagfish#Species, which appears to attempt to be comprehensive, does not include Eptatretus minor. Nor does the article on Eptatretus. Is "minor" another name for one of the listed species? I do see E. minor listed on FishBase, but don't know what to do from there. — Epastore (talk) 22:55, 20 February 2008 (UTC)

[edit] Heart System

The sentence "with a heart system that is more up to date than that of vertebrates..." is completely puzzling and deserves some explication. No, don't look at me to do it - I'm puzzled. Hue White (talk) 15:59, 21 May 2008 (UTC)