Keeper guide

Mexican Red Rump Growth Rate — How Fast Does Tliltocatl vagans Grow?

Tliltocatl vagans, commonly known as the Mexican Red Rump, has a moderate growth rate. Young spiders usually moult more often than large juveniles and adults, but no two Mexican Red Rumps grow at exactly the same speed.

At a glance

Quick facts

World
New World
Origin
Mexico and Central America
Lifestyle
Terrestrial
UK hobby rarity
Common
Maximum size
About 14–16 cm (5.5–6.25 in)
Growth rate
Moderate
Male lifespan
Roughly 4–6 years
Female lifespan
Often 15–20 years
Temperament
Often bold at feeding time; can be skittish and kick hairs
Venom
Venomous, but bites are not generally regarded as medically significant
Temperature
20–26°C
Moisture / humidity
Water dish plus a modest moisture gradient; avoid persistently wet substrate
CITES
CITES Appendix II; UK Annex B

How fast does it grow?

Mexican Red Rumps are generally described as moderate growers. That gives a useful expectation for Tliltocatl vagans, but it is not a promise that every sling will reach the same size at the same age.

Adult Tliltocatl vagans reach about 14–16 cm (5.5–6.25 in). The time taken to get there depends on sex, feeding, temperature and ordinary individual variation.

Moult intervals change with age

Small Mexican Red Rumps often moult more frequently because they are growing rapidly. As Tliltocatl vagans gets larger, the interval between moults normally becomes longer.

Do not treat a longer interval in an older Mexican Red Rump as a problem by itself. Look at appetite, body condition, retreat use and the spider's previous moult pattern.

Feeding and temperature

Feeding influences how quickly Tliltocatl vagans grows, but there is no benefit in keeping the abdomen constantly overfilled. Offer suitable meals and let appetite guide the interval.

A practical temperature range for Tliltocatl vagans is 20–26°C. Stable conditions are preferable to pushing the temperature upward in an attempt to force faster growth.

Male and female growth

Male Tliltocatl vagans usually mature sooner and have a shorter lifespan of about roughly 4–6 years, while females can live 15–20 years. That difference means two similar-sized juveniles may eventually follow very different timelines.

Sex cannot be judged reliably from growth speed alone. Use a suitable moult when possible instead of assuming a faster-growing Mexican Red Rump must be male.

Tracking growth

Record moult dates for Tliltocatl vagans and note approximate size when rehousing. You do not need precise measurements after every moult; a simple record is enough to show whether the spider is growing steadily.

Photographs taken after a Mexican Red Rump has hardened can also help show changes over time, provided the spider is not disturbed simply to get a measurement.

When growth means rehousing

Rehouse a Mexican Red Rump when its current enclosure no longer gives enough retreat space, substrate or safe access for maintenance. Do not move Tliltocatl vagans after every moult automatically.

Prepare the larger enclosure before the transfer. The goal is to keep each stage of Tliltocatl vagans's growth in housing that is secure and practical, not to race toward the adult enclosure.