H. Longimanus Parthenogenesis Project

[Henzeus]

Disclaimer:
- I am not a Professional Biologist / Entomologist / Arachnologist, just a random Hobbyist / Keeper.
- English is not my native language so bare with me

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Hello people of the Scientific and Academe route, as well as fellow hobbyist.

I am a keeper from the Philippines whom for my safety i would prefer not to disclose as of now.

Introduction:

I have recently acquired an H. Longimanus specimen (July 2023) as an addition to my collection of arachnids and found the lack of study in its reproductional behaviors; particularly its parthenogenetic properties. People online from communities in websites state that no formal documentation of the said scorpion have been made with the focus of Parthenogenesis. I personally have not found any complete documentation regarding this issue and yet hundreds of Hobbyist from my country, the Philippines, claim to have witnessed Parthenogenesis with their own specimen in captivity.

And so I would like to start a 2-3 year long study project in an attempt to document the said Parthenogenesis property of a Heterometrus Longimanus scorpion.

The project starts with my first H. Longimanus (Longi) who I have acquired from a Local breeder in Manila, Philippines as a 2nd instar. It has long molted 40 days ago into a 3rd instar H. Longimanus.

To add to my study I plan to acquire 4 more 2-4 instar H. Longimanus from completely different breeders (Captive bred) and raise them until maturity. (7-8 instar) And maybe adult specimen who i will personally try to check and confirm to the best of my abilities to have not yet mated / been mated.

End result I am looking for:
Confirm that a particular type of H. Longimanus (possibly endemic to the Philippines) displays parthenogenetic reproduction by documenting my own specimen' (Mainly raised from 2nd instar) Parthenogenetic reproduction while in my care. Rest assured that i will conduct my mini project with utmost honesty and to the best of my abilities.

Please excuse the lack of the amount of subjects for the study as I am a passionate hobbyist with a tight budget.

Anyways, I will keep on posting updates along the way and will start of with the pictures attached below:

The pictures here are right after i unpacked my Heterometrus Longimanus and found it with a molt, showing STRONG signs of Post Molt (Soft Exoskeleton, Grayish and Transparent.) 45 days in, I have been feeding it every 5 days for my first 5 feedings and transitioned into once a week feedings until the time I have posted. I plan to feed it once a week continuously until It has grown and I observe rejection / lack of feeding response frequency.

- I apologize in advance, I do not encourage handling with the pictures

 

[Wolfram1]

Interesting. Welcome to AB.

Do you know if the repoted parthenogenesis resulted in male and female offspring? Considering the sexual dimorphism this sp. is known for i do wonder if it is caused by Wollbachia or an innate ability to reproduce even if no mate is available, strange in any case.

The interesting thing is that Wollbachia, at least in many insects, usually causes a trend towards the female sex in affected populations.

While the parthenogenesis i have read about in Theraphosidae seems to result in an even split in sexes. It is therefore questionable if it played any role in those cases.


Keep us posted.

 

[Henzeus]

Thank you for the warm welcome!

And yes, according to 4 local breeders I have spoken to they have had broods with males and females in them. The wollbachia is something I did not think of, but I have read up on local groups about continuous reproduction despite being the sole H. longimanus in their collection and no nearby keeper present let alone a male H. longimanus which bacteria transmitted semen could be obtained. I don't know if i understood correctly what you were trying to point out, but i will try and get more information about Wollbachia and its relation, maybe discuss it with other local keepers.

Thank you, i definitely will! ^^

 

[GreekPrince]

The west have literally been fighting with you people for years about this subject. The Heterometrus species are not parthenogenetic at all however people in the Philippines believe theirs are special in some way. We have witnessed male and female H.Longimanus mating on camera but still it's insisted by the Phillipines that they're parthenogenetic.

Perhaps it lies in the locality of the Longimanus, so one of you decides to document your findings, which is great, but none of you ever follow through. Sorry but this has been attempted too many times on so many different forums and it always ends the same way, you never provide 'proof' or any indication of parthenogenesis in these species. You will get bored LONG before any relevant findings. It will be a waste of your time.

 

[Wolfram1]

The west have literally been fighting with you people for years about this subject. The Heterometrus species are not parthenogenetic at all however people in the Philippines believe theirs are special in some way. We have witnessed male and female H.Longimanus mating on camera but still it's insisted by the Phillipines that they're parthenogenetic.

Perhaps it lies in the locality of the Longimanus, so one of you decides to document your findings, which is great, but none of you ever follow through. Sorry but this has been attempted too many times on so many different forums and it always ends the same way, you never provide 'proof' or any indication of parthenogenesis in these species. You will get bored LONG before any relevant findings. It will be a waste of your time.

that is true, however there have been confirmed reports of parthenogenetic clutches in theraphosidae, while there are defenitly males and females in the species, so i do wonder if it might be an adaptation that lets them reproduce parthenogenetically in very rare cases and only in isolation, which makes reproducing the phenomenon incredibly hard.

@OP, i personally do not believe you will be able to achieve anything, but without trying we wont get anywere ether

 

[Matt Man]

we will welcome any solid research that can enlighten us on the subject

but like every communal experiment with T breeds, every one seems to slink away / disappear when the data goes against their theory

 

[Henzeus]

Oh, i forgot to mention that I will indeed be keeping each of them individually, The first H. longimanus i've received is living alone in a wide delicup. Sorry for that
Thank you for taking your time explaining it to me.

 

[The Snark]

Potentially flawed, invalid study. (I'm attempting to dredge up, recall, the basics of a proper scientific study from 40-50 years ago so please bear with me).

Objective: Valid records of Parthenogenesis incidence in a specific species.
Pre-requisites:
- Isolated laboratory conditions that eliminate all incidental instances of normal reproduction
- Recorded reproduction of species over multiple generations of multiple specimens establishing a valid control
- Accurate data on all specimens, age, sex, male to female ratios.
- Females isolated from males prior to maturity. The number of these females must be large enough so when parthenogenesis does occur it will be a ratio of barren females to those that successfully produce offspring
- Incidence of multiple parthenogenesis in specific specimens
- Female ratio of those that are able to parthenogenically reproduce to those that remain barren
Study extension
- General data of parthenogenically produced offspring, male to female ratio
- As above controls and incidence of parthenogenesis in parthenogenically produced second generations that in turn become parthenogenic - establishing a predictable norm of parthenogenesis within that species.

Quite possible I have missed a few steps above so consider all that a basic framework.
Possible -> for certain. I have already thought of several. I need the get out the manual on proper pathological lab procedures