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 12 h; T5 UVB 10 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 1.5-3directly under the tube when it is on
The latest saved PDF uses UVI 1.5-3 throughout, while the webpage retained 2-3. Use the current PDF range on both, as an optional canopy exposure patch with dense cover. This resolves a version mismatch; it does not establish a new physiological minimum or 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: Version consistency correction. 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
Drier phase
Lowland Guiana Shield rainforest and forest edge - Guyana and Suriname lineage
26-29 CDay ambient
22-24 CNight
36-39 CBasking
1.5-3T5 UVI*
12 hPhotoperiod
10 hT5 UVB duration
65-75 / 75-85%RH day / night
Mist 3-4x/wkSpray / rain
3-4Food offers
Annual schedule
Scroll sideways on smaller screens
| Month | Day ambient | Night | Basking | T5 UVI* | Photoperiod | T5 UVB duration | RH day / night | Spray / rain | Food offers | Status / breeding |
|---|---|---|---|---|---|---|---|---|---|---|
| January | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 75-85 / 85-95% | Heavy AM+PM mist daily | 4-5 | Short wet peak / breeding cue |
| February | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 70-80 / 80-90% | Mist 4-5x/wk | 4 | Rain easing |
| March | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 65-75 / 75-85% | Mist 3-4x/wk | 3-4 | Short drier phase |
| April | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 68-78 / 78-88% | Mist 4x/wk | 4 | Rain ramp-up |
| May | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 75-85 / 85-95% | Heavy mist 1-2x/day | 4-5 | Major wet-season build |
| June | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 80-88 / 88-96% | Heavy AM+PM mist daily | 4-5 | Peak wet season / breeding cue |
| July | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 78-88 / 88-95% | Heavy mist daily | 4-5 | Wet season / gravid females |
| August | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 72-82 / 82-92% | Mist 5-6x/wk | 4 | Wet season easing |
| September | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 65-75 / 75-85% | Mist 3x/wk | 3-4 | Main drier phase / nesting possible |
| October | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 65-75 / 75-85% | Mist 3-4x/wk | 3-4 | Drier phase |
| November | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 70-80 / 80-90% | Mist 4-5x/wk | 4 | Rain returns / conditioning |
| December | 26-29 C | 22-24 C | 36-39 C | 1.5-3 | 12 h | 10 h | 75-85 / 85-95% | Heavy mist 1-2x/day | 4-5 | Wet-season rise / breeding possible |
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 latest saved PDF uses UVI 1.5-3 throughout, while the webpage retained 2-3. Use the current PDF range on both, as an optional canopy exposure patch with dense cover. This resolves a version mismatch; it does not establish a new physiological minimum or optimum.
Taxonomy
Modern phylogenetic work restricts Polychrus marmoratus sensu stricto primarily to Guyana and Suriname, so this protocol is deliberately based on the Guiana Shield lineage rather than older broad 'marmoratus' records from elsewhere in South America.
Habitat and seasonality
The species is highly arboreal and occupies forest and forest-edge vegetation. Guiana temperatures and photoperiod remain almost constant year-round; seasonal rainfall peaks are the main environmental cue.
Humidity and hydration
Maintain high humidity with strong airflow and regular leaf-wetting. Experienced Guiana-line husbandry maintains at least about 75% RH whenever possible and uses heavy morning/evening misting to promote drinking. Reduce frequency in drier phases but never allow chronic dehydration.
Diet
Use a varied arthropod-rich diet with fruit/berries as a regular supplement. Captive Guiana-line animals readily take crickets, roaches, grasshoppers, phasmids, katydids, mantids, caterpillars, spiders, flies and beetle larvae. Green leaves are often ignored.
Reproduction
Successful Guiana-line captive breeding has been triggered during simulated wet seasons. Timed copulations produced laying at about 94-120 days. Practical clutch expectation is roughly 6-10 eggs, although 12 have occurred in an over-conditioned female.
Incubation
Direct Guiana-line breeding success occurred around 25.5-26.6 C with a small night drop, producing hatchlings after about 145-160 days. These data are preferred over generic high-temperature iguanian incubation.
Nest warning
Provide several nesting choices across a thermal gradient, including elevated planters with loose root-filled substrate. Inadequate nesting conditions and over-conditioning may increase dystocia risk.
Social warning
Pairs or trios can show subtle hierarchy and breeding harassment. Individual housing outside breeding is safest; separate any animal losing access to basking, food or preferred canopy space.