Blue Stick Insect (Ramulus Nematodes)

The blue stick insect (Ramulus nematodes), native to Khao Lak in Thailand, is an exceptionally beautiful phasmid species. Males of this species display a rare blue colouration, a colour uncommonly seen in the phasmid world, which significantly contributes to their popularity among enthusiasts. Females, while not blue, are equally cherished for their distinctive appearance, particularly the 'Mickey Mouse'-like ear protrusions on their heads.

Nymphs: Newly hatched nymphs measure ~20mm in length and are extremely slender. They display a brown and white speckled colouration. Nymphs typically mature to adulthood after about 3 months.

Females: Both adult females and males are wingless. Females exhibit a range of colouration from light browns to olive greens and reach impressive lengths of ~140-170mm. They are notably larger and thicker than males. One of their most distinctive features is the pair of large, brown, lobe-like expansions on their heads, reminiscent of Mickey Mouse’s ears. These horn-like projections give them a unique and adorable appearance. To complete their appearance, females possess short antennae, measuring ~20mm in length.

Males: Adult males are remarkably thin and one of the slenderest phasmid species. They are notably shorter than females reaching ~100mm in length. Males display a stunning electric blue to turquoise colouration across their entire body, with the intensity of this blue varying between individuals. Interestingly, there exists a colour variation within this species where males exhibit a red colouration. Their legs showcase a gradient, transitioning from an orangey bronze colour near the body to a deeper brown or black towards their toe pads.

Females live for ~12-14 months.

Males live for ~10-12 months and mature faster than females.

Blue stick insects are a delicate phasmid species and easily detach their legs by a mechanism called autotomy – this is the ability to voluntarily ‘throw’ their legs off when threatened. Therefore, blue stick insects have to be handled with care.

As a nocturnal species, during daylight hours, blue stick insects remain docile and still. They often stretch their front legs forward, aligning their body to mimic the appearance of a slender branch. At night, they become more active and feed.

Blue stick insects primarily feed on bramble, raspberry, rose and oak species. When selecting food plants, ensure they are free from insecticides or other harmful chemicals.

Before offering food to your phasmid, it's advisable to wash the cuttings with water.

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 phasmids 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.

The blue stick insect is an easy to medium-care phasmid.

Temperature: Maintain temperatures between 21°C to 26°C during the day and night. This species can be kept at room temperature without issues. The warmer they are kept, the quicker they develop.

Humidity: This species appreciates average humidity levels of approximately 60-70%. To maintain appropriate humidity, mist the enclosure every day, focusing on the food plants – this is particularly important due to their fragile nature. Adequate moisture is crucial for successful moulting, which is essential for the insect's growth and development. Use dechlorinated water for misting to prevent potential harm. A substrate of paper towels or coir (coconut fibre) can help maintain higher humidity levels.

Lighting: Mimic natural day/night cycles using either natural or artificial lighting.

Blue stick insects require spacious enclosures due to their considerable length and delicate, elongated legs. It's crucial to note that an adult female with fully extended legs can span over 25cm in length. To accommodate for this, a minimum enclosure size of 60cm x 45cm x 45cm (width x length x height) is strongly recommended. Additional vertical space is particularly beneficial for these phasmids, as it provides ample room for them to hang vertically during the critical moulting process. Given the fragile nature of this species, it's imperative to avoid overcrowding.

Proper ventilation is equally important as maintaining high humidity. Ensure ample airflow to prevent stagnant conditions and mould developing. 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 when they often hang from the ceiling.

Breeding blue stick insects is relatively straightforward, as they readily reproduce under suitable conditions once they reach maturity. During mating, you may observe males "piggy-backing" on females, a behaviour characteristic of many phasmid species.

Unlike some other phasmid species, the blue stick insect cannot reproduce via parthenogenesis, so sexual reproduction is necessary for viable eggs to be produced.

Following successful mating, females typically begin laying eggs a few weeks later, depositing 1-3 eggs per day. The eggs are distinctively flat, thin, and brown in colour, measuring ~6mm in length. The surface of the eggs features small grooves running along the length. Within these grooves are subtle indentations. Females deposit these eggs on the enclosure floor using a whip-like movement of their abdomen.

Incubation takes about 4-5 months at a humidity of ~70% and temperature between 18°C and 25°C. Lower temperatures will extend the incubation period. Ensure they receive daily light exposure and regularly check for mould growth.

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.