Keeper timer setting
T5 UVB: one hour later on, one hour earlier off
During active care — ON: 1 hour after daylight starts.
OFF: 1 hour before daylight ends.
During hibernation / full brumation: T5 UVB OFF (0 hours). In transition months, keep UVB off while dormant and use the active timer only once the animal is warmed and active.
October: daylight 10 h; T5 UVB 8 h.
The active T5 duration is the photoperiod minus two hours. Example: daylight 08:00–20:00 means UVB 09:00–19:00. Follow the monthly UVI strength measured beneath the tube and provide access to shade. This timing rule does not introduce hibernation for species whose schedule has only a mild or active winter rest. If an older combined heat / UV column is present, the new T5 UVB duration column governs UVB timing; existing heat settings are preserved.
UVI beneath the optional T5 tube
Working exposure targetOctober target at normal back height
UVI 1-2directly under the tube when it is on
The retained range remains a provisional captive working target. No new species-specific result was found that clearly requires a numerical change. Retaining it is not certification of an experimentally established optimum.
Your measuring point
Measure at the animal's normal back height directly beneath the brightest accessible part of the T5 strip, positioned toward the middle/back. The animal can enter and leave this area freely.
Keep a lower-UVI gradient and fully covered refuges near UVI 0. This is the optional exposure area, not the average across the cage.
Use a UV Index meter, such as a Solarmeter 6.5/6.5R. Warm the tube for about 30 minutes; keep reflector, guards and mesh in place. Raise or lower the fixture within its manufacturer's minimum-distance guidance, then recheck the reading and every higher accessible surface.
Evidence level: Provisional retention. These are working recommendations, often inferred; exact species optima and seasonal UV dose usually have not been measured. Log lamp-on time and animal behaviour as well as UVI.
Baines et al. (2016), UV-Tool · Muryn, Baines and Dishman (2026), Reptile Lighting Guide V10
October management
Selected automatically using the Netherlands date
Seasonal taper
Cold arid volcanic outcrops - Butaco Creek, northern Tromen massif, Neuquen, Argentina
13-17 CDay ambient
6-9 CNight
34-37 C limitedBasking
1-2T5 UVI*
10 hPhotoperiod
8 hT5 UVB duration
Minimal local sprayMoisture
1-2 then stopFood offers*
Annual schedule
Scroll sideways on smaller screens
| Month | Day ambient | Night | Basking | T5 UVI* | Photoperiod | T5 UVB duration | Moisture | Food offers* | Seasonal management |
|---|---|---|---|---|---|---|---|---|---|
| January | 6-10 C | 4-7 C | Off | Off | 0-8 h | Off (0 h) | Water check; no spray | None | Deep brumation |
| February | 6-10 C | 4-7 C | Off | Off | 0-8 h | Off (0 h) | Water check; no spray | None | Deep brumation |
| March | 8-12 C | 4-7 C | Off; 34-36 C late | Off / 1 | 8-9 h | Off during rest; 6 h to 7 h when active | Water check; no spray | None / restart late | Staged emergence late |
| April | 13-17 C | 6-9 C | 35-38 C | 2-3 | 10.5 h | 8 h 30 m | Light local spray every 10-14 d | 2-3 | Emergence / reconditioning |
| May | 17-21 C | 8-11 C | 37-40 C | 3-4 | 12 h | 10 h | Occasional local spray | 4-5 | Full activity / courtship watch |
| June | 19-23 C | 9-12 C | 38-41 C | 3-4 | 14 h | 12 h | Occasional local spray | 5-6 | Peak activity / mating watch |
| July | 20-24 C | 10-13 C | 38-41 C | 3-4 | 14.5 h | 12 h 30 m | Occasional local spray | 5-6 | Peak activity / possible gestation |
| August | 19-23 C | 9-12 C | 38-40 C | 3-4 | 13.5 h | 11 h 30 m | Light local spray every 10-14 d | 5-6 | Possible gestation / birth watch |
| September | 17-21 C | 8-11 C | 36-39 C | 2-3 | 12 h | 10 h | Light local spray every 10-14 d | 4-5 | Birth watch / recovery |
| October | 13-17 C | 6-9 C | 34-37 C limited | 1-2 | 10 h | 8 h | Minimal local spray | 1-2 then stop | Seasonal taper |
| November | 8-12 C | 4-8 C | Off | Off | 8 h | Off (0 h) | Water check; no spray | None | Cooling / brumation |
| December | 6-10 C | 4-7 C | Off | Off | 0-8 h | Off (0 h) | Water check; no spray | None | Deep brumation |
Keeper notes
Use measured gradients and animal behaviour, not single thermostat readings
T5 UVI measurement
Measure UVI at normal back height directly beneath the brightest accessible part of the optional T5 strip. Place the strip toward the middle/back with free access to and away from it; preserve a gradient into fully covered refuges near UVI 0. These numbers describe the exposure area, not the whole enclosure or a daily average.
UVI review
The retained range remains a provisional captive working target. No new species-specific result was found that clearly requires a numerical change. Retaining it is not certification of an experimentally established optimum.
Identity and range
Phymaturus delheyi is a valid patagonicus-group species known only from volcanic rims around Butaco Creek on the northern Tromen massif, Neuquen, Argentina. The type locality is at about 1810 m and the species is extremely localized.
Habitat and climate
Animals were observed basking on rocky outcrops and retreating into crevices. Tromen climate information near 1800 m describes severe snowy winters, warm summer days with large daily thermal swings, about 13 C annual mean temperature and roughly 350 mm annual precipitation.
Thermal management
No direct preferred-temperature study was located for P. delheyi. Use 38-41 C only as a local basking-surface starting point with cool ambient air and immediate access to deep shaded crevices. UVI 3-4 is an operational starting point rather than a measured species requirement.
Diet
The original species account directly observed feeding on both plant matter and arthropods. Base adult feeding on varied fibrous greens, weeds, browse and flowers, with small invertebrates as an occasional minor component rather than the staple.
Breeding evidence
Viviparity is confirmed and one captive female from the original species account produced two offspring. No species-specific mating month, gestation length or birth season was published; the May-July courtship and August-September birth-watch windows are explicitly comparative working periods.
Keeper warning
Cool only healthy, conditioned adults after feeding has stopped and the gut is clear. Use controlled above-freezing refuges rather than outdoor freezing exposure. Record starting mass, reweigh every 2-4 weeks, and reverse cooling for weight loss, dehydration, respiratory signs or persistent activity without digestion.