pterinochilus murinus growth rate

[christopher furlong]

Hi everyone,
I am posting this thread on behalf of my friend. We purchased two pterinochilus murinus from an online dealer which are both from the same egg sack. mine has molted five times an is about 2 1/2" form L1/R4.His on the other hand has molted five times and is barley 1 1/2" L1/R4 And is not showing much growth rate on each successive molt.I suggested it was the heat and not feeding enough.He uses a heat mat and the temp in his tank reads 76 F and humidity reads 75% and feeds them 3 prey items each week.I keep mine at 85/88 F .with humidity at 65% and also offer 3 prey items each week.Can anyone shed any light on this matter.
Kind regards
Chris

[christopher furlong]

I would just like to add that his tarantula is not very active and shows no signs of pterinochilus murinus "reputation" where as mine, all you have to do is open the lid to feed and it throws a threat display at me. His seems to be a "nice" P.murinus.I suggested it will change its "personality" with each molt.
Thanks all
Chris

[Mark Harrison]

Tbh chris i dont keep any of my P.murinus at that level of humidity, the three juve's i have one is approx one month ahead in terms of moulting and growth, all have been fed the same amount and kept at the same heat/humidity. You said you keep you murinus between 85/88F, thats roughly 29-31 c and your friend keeps his at a round 24 c. I would say that due to you keeping your spider warmer its metabolism is faster and so it has grown at a faster rate, this is thought to shorten a spiders life span. Do you keep the Murinus at that temp all the time?

[christopher furlong]

Hi mark,
Yes i keep all my t"s at that temp! With a night time drop to 73F/77F. I have them in a cupboard with a heater and a humidifier controlled by a thermostat/humidistat. I have the temp/humidi probes in a separate tank, that is set up the same for species that require high humidity. For T"s that requir a lower humidity I keep on a drier substrate and only spray when needed. I test these drier tanks with separate controlls.
Kind regards
Chris

[Mark Harrison]

Hi mark,
Yes i keep all my t"s at that temp! With a night time drop to 73F/77F. I have them in a cupboard with a heater and a humidifier controlled by a thermostat/humidistat. I have the temp/humidi probes in a separate tank, that is set up the same for species that require high humidity. For T"s that requir a lower humidity I keep on a drier substrate and only spray when needed. I test these drier tanks with separate controlls.
Kind regards
Chris

Chris, i was not questioning your husbandry when i asked if you kept all your tarantula's at that temperature consistently. We all keep our T's differently with varying results in growth time etc, i just felt that is why your tarantulas growth superceded your friends due to the higher heat. The reason i do not keep my T's at that heat is a preference, i keep the heat in my spider room at roughly 25/26c (77-79F) depending on how hot the room is naturally and cool the spiders at night, hoping to try and simulate the natural fluctuations in temp/humidity that occur in the wild. If im correct the humidity in an average central heated room is between 40-50% meaning it wouldnt take much to keep up a 60-70% humidty that some spiders require, so in a small cupboard the humidity anyhow may be higher than 40%.