Phyllium gantungense "Rizal" is a magnificent leaf insect species native to Rizal in the Philippines. It is popular among enthusiasts due to its unique behaviour, which includes the ability of adults to release a lemon-like scent when threatened, an aroma that interestingly resembles the smell of sweets.
Appearance
The appearance of Phyllium gantungense "Rizal" varies significantly depending on the insect’s sex and developmental stage.
Nymphs: Newly hatched nymphs are dark brown or black with white highlights, measuring ~16mm in length and ~7–8mm in width. They strongly resemble large ants in appearance. Within several weeks of feeding, they transition to the leaf insect's characteristic green colouration.
Females: Adult females of Phyllium gantungense "Rizal" have an exquisite body shape. While flattened, they have less irregular bodies compared to other species, featuring a box-like form and uniquely shaped abdomen. They have enlarged forelegs and are almost exclusively green in colour with brownish-red variations on their body. Females reach ~90–100mm in length. They possess large, broad, non-functional forewings that cover almost the entire abdomen. Two short antennae, each measuring about 5mm in length, complete their appearance.
Adult female - look at that really unique and pointed abdomen which differs to other leaf insect species
Adult female (left) and male (right)
Males: Adult males of Phyllium gantungense "Rizal" are smaller, reaching sizes of ~55–60mm. Like the females, they are green in colour but possess fully developed wings enabling flight. Their antennae are notably longer than those of females, measuring about 50mm in length.
Lifespan
Females live for ~8-12 months.
Males live for ~6-8 months and mature faster than females.
Behaviour
Phyllium gantungense "Rizal", like most other leaf insect species, are docile by nature and typically remain motionless during the day before feeding at night. However, this species possesses some unique characteristics. They can release a defensive spray with a distinct lemon-like scent, which interestingly smells sweet. Males tend to release this scent much more frequently than females.
In addition to their chemical defence, individuals of this species are particularly clingy when handled. Adult females especially tend to grip tightly when one attempts to remove them from branches.
Despite these traits, Phyllium gantungense "Rizal" are easy to maintain in culture due to their strong breeding instincts.
Newly hatched nymphs can exhibit hyperactive behaviour. This initial burst of activity gradually settles as they acclimate to their environment.
Four adult females (they fortunately didn't spray me with their lemon scent here)
Diet
Phyllium gantungense "Rizal" primarily feed on bramble, oak, and salal species. They are known to be heavy feeders, often consuming large amounts of leaves. I jokingly refer to them as “the cows of leaf insects” because of how much they eat. Because their feeding instinct is so strong, this can sometimes lead to cannibalism, especially if food is limited. Therefore, it’s important to ensure plenty of fresh leaves are always available. When selecting food plants, ensure they are free from insecticides or other harmful chemicals. It is also worth noting that Phyllium prefer older, darker-coloured leaves over fresh growth, especially when it comes to bramble. This preference is particularly important for nymphs, as new growths can be poisonous.
Adult female on their staple food plant I provide, bramble
Before offering food to your Phyllium, it's advisable to wash the cuttings with water.
Young nymphs face a unique challenge when it comes to feeding. Unlike their adult counterparts, they struggle to eat from undamaged leaves, which can be a significant cause of mortality in captive-bred populations. To assist them, carefully cut the edges of leaves using scissors. This simple step can greatly improve nymph survival rates.
To maximise plant longevity and minimise maintenance, consider keeping the food plant in a pot of water within the enclosure. However, take care to cover or reduce the size of the pot's opening to prevent the Phyllium from accidentally falling in and drowning.
Always provide a fresh source of food. On average, clean out the enclosure once a week, replacing old food with fresh offerings and adding new substrate to remove waste. This weekly maintenance is also an ideal time to collect any eggs that have been laid.
Environmental conditions
Phyllium gantungense "Rizal" is another leaf insect species that is relatively easy to accommodate and rear in terms of its low level of environmental requirements.
Temperature: Maintain daytime temperatures between 22°C and 26°C, allowing them to cool to 18°C – 20°C at night. Room temperatures are sufficient for this species.
Young L2 nymph up close
Three adult females
Humidity: Humidity plays a vital role in the care of leaf insects. Aim for high humidity levels of ~60–80%. To achieve this, spray the enclosure once or twice daily, focusing on the food plant. Proper moisture is essential for successful moulting, a process by which the Phyllium grows and develops. When misting, use non-chlorinated water to avoid potential harm. To maintain a high humidity consider using paper towel or coir (coconut fibre) as a substrate.
Lighting: Mimic natural day/night cycles using either natural or artificial lighting.
Housing
Provide an enclosure at least three times the insect's length in height and twice in width. This is particularly important for Phyllium gantungense "Rizal" because of their more cannibalistic nature. A minimum size of 30cm x 30cm x 45cm (width x length x height) is recommended for this species. The more height available, the better, as this allows the leaf insect more room when hanging down during moulting.
Group of males and females (adults and sub-adults) in their netted 40cm*40cm*60cm, W*L*H enclosure
Two males (L4 on the left and L5/sub-adult on the right). You can see the wings on the sub-adult starting to expand and develop
For young nymphs, two enclosure setups are advisable: either a large enough space where the food plant doesn't touch the enclosure walls, preventing nymphs from wandering off, or a smaller enclosure allowing nymphs to easily return to their food plant. In either case it is crucial nymphs can find their way back to feed.
Proper ventilation is as important as maintaining high humidity to create the airy environment this species enjoys. Ensure ample airflow to prevent stagnant conditions. At a minimum, a mesh or netted roof is recommended. Netted material also provides easier grip for the insects, which is especially beneficial during moulting.
Breeding, incubation, and hatching
Both males and females are common in Phyllium gantungense "Rizal" populations, enabling sexual reproduction. After their final moult to adulthood, males and females begin mating within 2–3 weeks, with females laying fertilised eggs shortly after.
Females typically lay 1–3 eggs per day over a period of about three months, dropping them to the enclosure floor with a whip-like movement of their abdomen. They can come in light brownish orange, tan, and grey colourations, with a surface characterised by distinct small pits. These pits are a key identifier of this species, leading to its classification as an "8-pit egg type". Upon exposure to humidity, these eggs develop sparse, long fringes. The eggs measure ~4mm in length and ~1.2mm in width.
Eggs being incubated using the vermiculite and bottle cap method
Incubation usually takes 4–5 months but can extend to 7–8 months depending on conditions. Eggs should be maintained on moist substrate such as paper towel or coconut fibre at 20°C–25°C, ensuring daily light exposure and monitoring for mould. If you notice mould on an egg, carefully remove it from the container. You can attempt to gently wipe off the mould using a clean paper towel or soft brush. However, if the mould growth is extensive, it's best to discard the egg to protect the health of the others. If mould has developed, thoroughly clean the container housing the eggs. Pay particular attention to the substrate, especially if using paper towels. Vermiculite or coconut fibre substrates are less prone to mould growth.
In the absence of males, female Phyllium gantungense "Rizal" can reproduce via parthenogenesis. This process produces unfertilised eggs that hatch into genetic clones of the female.
Adult female: the venation-like markings on her wings are a remarkable adaptation for camouflage
