Common among most marine invertebrates, T .australiensis has a pelagic-benthic biphasic life cycle with a larval stage to assist in dispersal. There are four stages of larval development which approximately lasts for 45 days (see Development) (Jones, 2006). The nisto recruit then settles on the substrate and undergoes  metamorphosis into the juvenile form. To develop into a reproductive adult, the juvenile undergoes ecdysis and moults (see Development). Once matured,the adults sexually reproduce and fertilisation of the eggs occurs externally in the water column (see Reproduction). These eggs are carried by the female in a brood until the larvae hatch (Wakabayashi & Phillips,2016). A simplified life cycle of T .australiensis is shown in Figure 4.

Larval Development

T. australiensis larvae are positively phototactic meaning they are attracted to light. This explains why the pelagic larvae during the first phase of the lifecycle can be found on the surface of the water column. There are four stages of larval development which approximately lasts for 45 days (Jones, 2006). The larvae in the first four stages are known as ‘phyllosoma’ and the individual in the post-larval stage is known as a ‘nisto’ (Kizhakudan & Krishnamoorthi, 2014; Wakabayashi & Phillips, 2016). In the first larval stage, the phyllosoma has an unsegmented uniramous antennule and unsegmented eyes, the first maxilliped and pleopods are absent, and the telson is undifferentiated.The phyllosoma is in the first larval stage for a duration of approximately seven days. In the second larval stage, the eyes are segmented, the antennules become biramous but are still unsegmented, uropods begin to develop, pleopods and gills are still absent, and telson is still undifferentiated. The phyllosoma is in the second larval stage for a duration of approximately five days. In the third larval stage, the antennules are biramous and have become unsegmented, the biramous antennae are unsegmented and flattened, the first maxilliped and pleopods start developing, uropods are well developed, gills are still absent, telson is differentiated. The phyllosoma is in the third larval stage for a duration of approximately seven days. In the fourth larval stage, the antennae become segmented, and the gills are present. The phyllosoma is in the fourth larval stage for a duration of approximately seven days. Finally, the post-larval stage is where the phyllosoma develop into a nisto. The post-larval stage is short lived (approximately four days) where the nisto is a non-feeding organism. It signals the end of the planktonic phase and the body plan resembles that of a translucent adult form. Thus, the nisto are sedentary and begin life on the benthos. Relatively soon after the larvae has transformed into the nisto, the nisto metamorphoses into a juvenile which is characterised by its now hardened exoskeleton and begins feeding (Kizhakudan & Krishnamoorthi, 2014; Wakabayashi & Phillips, 2016). Figure 5 shows a simplified four stage life of the larva.
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Ecdysis

The phylum Arthropoda are a part of the superphylum Ecdysozoa. This means that development in arthropods occur through ecdysis as opposed to direct development. Ecdysis is the growth process where organisms, such as T. australiensis, moult their exoskeleton (chitinous cutile) in order to grow and develop (Mikami, 2005; Jones, 2006). There are three stages of moulting an exoskeleton: post-moult, inter-moult, and pre-moult. During the post-moult stage, the newly formed cuticle under the old exoskeleton is vulnerable and soft which soon will harden and develop into the new exoskeleton. The cuticle generally takes 48 hours to harden. The post-moult stage is the most vulnerable for the organism. Once the exoskeleton has become rigid the organism has now entered the inter-moult stage. The pre-moult stage is the most complex. First,the epidermis and cuticle begin to separate resulting in a wide “transparent zone”. When the transparent zone is wide enough new soft and irregular setae expand into the space. Once the setae become hard, a new layer of cuticle develops externally to the epidermis (Jones, 2006). Ecdysis is the actual moult activity of the exoskeleton after pre-moult. This is where the old exoskeleton is fully expelled off the body (Mikami, 2005).

T. australiensis is a carnivorous specialised predator who scavenges the benthos for marine invertebrates (Johnston & Yellowlees,1998; Johnston & Alexander, 1999). They prey upon bivalves, other small crustaceans and polychaetes by searching and digging through the substrate (Johnston & Yellowlees, 1998; Johnston & Alexander, 1999). The foraging and ingesting behaviour of this species is highly complex for their mandibles are not evolved for crushing (Figure 6). Thus, T. australiensis have highly specialised oral appendages and digestive system which synchronise to assist in consuming large and rigid prey items (see Digestive System).
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Foraging behaviour

At night T. australiensis hunt for their prey buried in the substrate by using one of two processes: digging or probing (Johnston & Yellowlees, 1998). Digging occurs when the organism expands its third, fourth and fifth pereiopods and inserts them into the benthos. While inserted in the benthos, the organism excavates the substrate by moving the pereiopods inward and up towards the centre of its body. As the pereiopods are moving upwards, the organism jumps while moving to the side. The pereiopods expand again and are reinserted into the benthos repeating this process. This is compared to the probing process where the organism uses the first and second pereiopods to probe the benthos. First, the organism lowers its body to ground using its third, fourth and fifth pereiopods. Then the first and second pereiopods continuously probe the ground in front of the body as it slowly walks forward. If the organism is successful in locating a prey item using either of the two above techniques, then it will lower its body even further, place its antennae on the ground and continuously probe the prey item. The organism will then capture its prey using its pereiopods (Johnston &Alexander, 1999).
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Accessing prey

As mentioned above, the mandibles are not able to crush through the hard exoskeletons of its prey. Therefore, T. australiensis have developed a process to assist in the acquisition of the soft flesh. If they encounter a prey item, such as a bivalve, the organism must first position itself over the prey item. It then inserts the third pereiopods between the two shells and pries them open. Utlising the first and second pereiopods the organism then detaches and removes the prey item from the shell valves (Johnston & Yellowlees, 1998). The prey item is now ready for ingestion.
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Ingesting behaviour

Once the prey has been located and accessed, the organism must place the food item into the oral cavity. Still holding the prey item, the first and second pereiopods move the food towards the mouth. The crista dentata, propodus and dactylus located on the third maxillipeds (Figure 7) grasp the prey item and move it towards the mandible. The mandibles then grip onto the prey item in a shearing motion. The third maxillipeds then pull and stretch the prey item away from the mandible. The second maxillipeds (Figure 8) then use their propodus and dactylus to cut the prey item between the mandible and the third maxilliped. The first maxilla (Figure 9) then help to shovel the prey gripped by the mandibles into the oesophagus. Simultaneously, the third maxillipeds open its crista dentata, propodus and dactylus to rearrange the remaining of prey item in preparation for the next insertion into mandibles (Johnston & Alexander, 1999).

Note, that the second maxilla and first maxillipeds are not used during the feeding process (Figures 10 & 11 respectively). The second maxilla help regulate water movement over the gills (see Respiratory and Circulatory System).

The digestive system of T. australiensis is an internal tube that is made up of three primary sections: the foregut, the midgut and the hind gut (Johnston & Alexander, 1999; McGaw & Curtis, 2013). The foregut is made up of the cardiac and pyloric chambers which are specialised for both extracellular and mechanical digestion. First, the ingested food enters the cardiac chamber and undergoes mechanical digestion with the aid of the gastric mill apparatus. The gastric mill possesses specialised teeth which assist in the breakdown of particles. The gastric teeth of T. australiensis are not as calcified as the gastric teeth of other carnivorous decapods. With the aid of the foregut muscles and the gastric mill, the broken down food then moves through the pyloric chamber into the midgut. These foregut muscles and the gastric mill movements are regulated by the stomaogratric ganglion (see Nervous System). The pyloric chamber filters the food particulates out of the digestive system allowing only liquid forms of food to enter the hepatopancreas in the midgut. The midgut of T. australiensis is fairly short (~3-5mm). The hepatopancreas is the site of intracellular digestion of food. Once all nutrients have been taken from the food, the hindgut disposes of a peritrophic membrane which contains the metabolic waste. The hind gut is essentially a long cuticle extending down the length of the abdomen to the anus on the ventral side of the body anterior to the telson. With the aid of longitudinal and circular muscles the waste is disposed of into the surrounding environment (Johnston & Alexander, 1999; McGaw & Curtis, 2013). Figure 12 shows a simplified diagram of the digestive system in T. australiensis.

Gas exchange in T. australiensis occurs via gill ventilation. This means that as water moves over the gills oxygen is taken in and carbon dioxide is expelled, hence why it is called ‘gas exchange’. The gills are protected by the branchial chambers (Figure 13) and the second maxilla (Figure 10) assists in water movement over the gills (Wilkens, 1981). Most decapods are able to ‘reverse pump’ water over gills which aids in flushing detritus particulates out of the gills (Wilkens, 1981).