The bug guide

An identification and information guide for Moreton Bay and Balmain bugs Key di˜erences between Moreton Bay bugs and Balmain bugs

The key di˜erences between Moreton Bay bugs and Balmain bugs In addition, Moreton Bay bugs have no postero-lateral teeth on relate to eye position and the presence (or absence) of postero- the head, while Balmain bugs have 6–8 individual teeth on each lateral teeth on the ‘head’. side of the head (Figure 1). Moreton Bay bugs have their eyes positioned laterally on the outer edge of the carapace, while Balmain bugs have eyes positioned centrally on the dorsal surface of the carapace (Figure 1).

Eyes positioned laterally on the outer edge of the carapace Eyes positioned centrally on the carapace surface

Lack of segmentation Presence of (postero-lateral teeth) segmentation on the body (postero-lateral teeth) on the body

Moreton Bay bug Balmain bug

Figure 1. Distinguishing features of Moreton Bay and Balmain bugs (dorsal view) Bug classification key

Position of eyes

Eyes positioned laterally on Eyes positioned centrally the outer edge of the carapace on top of the carapace

Moreton Bay bug Balmain bug Minimum size limit 7.5 cm Possession of berried Possession of berried females females not permitted permitted above this size

• Cervical incision • Cervical incision gap is narrow gap is wide • Dorsal surface is covered with soft • Speckled legs • 6–7 postero-lateral • 7–8 postero-lateral hairs that have a • Striped legs teeth teeth • Red/brown colouration ‘velvety’ feel • Multiple incisions • No incisions • Tail is white/pale running across the running across the in colour mouthparts mouthparts

Ibacus chacei Ibacus brucei Ibacus alticrenatus Thenus australiensis Thenus parindicus (‘Garlic bug’) (‘Honey bug’) (‘Velvet bug’) (‘Reef bug’) (‘Mud bug’) Minimum size Minimum size Minimum size limit 10.5 cm limit 7.5 c m limit 7.5 c m Moreton Bay bugs

Moreton Bay bugs live in muddy or sandy bottoms up to a depth Thenus parindicus of 100 m. They belong to the genus Thenus of which there are two (Mud bug) main species—reef bugs (Thenus australiensis) and mud bugs The mud bug di˜ers from the reef bug by the presence of stripes on (T. parindicus). its walking legs (Figure 2). Mud bugs live on muddy substrates in depths of 10–50 m. While Thenus australiensis mud bugs have a similar distribution to reef bugs, they are more (Reef bug) commonly associated with commercial catches of tiger, banana The reef bug is distinguished by its reddish-brown colour and the and endeavour prawns. presence of speckling on its walking legs (Figure 2). Reef bugs live on sandy substrates in o˜shore waters in depths of Legal size: Minimum carapace width 7.5 cm. The possession of 30–100 m and are associated with scallop and redspot king prawn berried (egg-bearing) females above this size is permitted. fisheries. They are distributed from northern Australian coastal waters from northern to Shark Bay in .

Legal size: Minimum carapace width 7.5 cm. The possession of

berried (egg-bearing) females above this size is permitted. Moreton Bay bugs Figure 2. 2. Figure bug) (Reef australiensis Thenus colour Reddish-brown Dist on walk on S peckling or spots spots or peckling inguish g legs ing legs

Distinguishing features of Moreton Bay bug s bug Bay Moreton of features Distinguishing

ing Moreton Bay bug features cies ( pecies rsal view) view) dorsal Thenus parin Thenus Stripes on walking legs legs walking on Stripes (Mud bug) bug) (Mud cus dicus

Moreton Bay bugs Balmain bugs th (Figure 3). Thegarlicbugalsohas 3). (Figure teeth 6–7 postero-lateral Balmain bugs coastal waters. waters. coastal m is the This 4). (Figure mouthparts its ing across runn incisions multiple generally and gap incision anarrow of presence the by species is dist bug garlic The b (Garlic chacei Ibacus fishery. prawn k eastern the with associated often waters deeper the in found are They Australia. Western in Geraldton to around central from waters coastal Australian southern in distributed Balm of berried (egg-bear berried of size: Legal n bugs b ain bugs tion as smooth bug) bug) smooth as lation legis in to ug—referred n Balmain bug species caught species bug ain Balmain Minimum carapace width 10.5 cm. The possession possession Minimum carapacewidth10.5cm.The ng to the genus genus the to elong guished from the other Bal other the from inguished g) fe ing) les is prohibited. is prohibited. males Ibacus Ibacus and are are and in Queensland Queensland in in bugs bugs main

ing by The b (Honey brucei Ibacus latera nd is usually fo is usually bugs, and is re bug This co in pale or white sometimes is also tail The feel. a‘velvety’ it give which hairs, soft with is covered bug this of surface dorsal The b (Velvet a Ibacus water. deeper slightly in as common as is not bug This ru nnin of berried (egg-bear berried of of berried (egg-bear berried of size: Legal Legal size: size: Legal

the the

hone l teet

g presence across lticrena eferred to in legislation as deepwater bug) bug) deepwater as legislation in to ug—referred tion as shovel-nosed lobster) lobster) shovel-nosed as lation legis in to ug—referred y bug h (Figure (Figure common compared to to compared uncommon latively Minimum carapace width 7.5 cm. The possession possession Minimum carapacewidth7.5cm.The Minimum carapace width 7.5 cm. The possession possession Minimum carapacewidth7.5cm.The i

it s

of tus s

distinguished a mouthparts mouthparts

3). wide g) fe ing) g) fe ing)

d in und in mu Additionally,

incision les is prohibited. is prohibited. males les is prohibited. is prohibited. males

as thegarlicbugandisfound (Figure (Figure

from from

ch deeper water ( water deeper ch

gap gap

the the the the

4). and

honey other

generall

Balmai the garlicandhoney bu g 00 m). >200 y ha 7– n s 8 bu no postero- g species

i ncisions

lour. Distinguishing Balmain bug features (head and body)

Gap between the head and the body Gap between the head and the body (cervical incision) is narrow (cervical incision) is wide

6–7 segments 7–8 segments (postero-lateral teeth) (postero-lateral teeth) on the body on the body

Ibacus chacei Ibacus brucei (Garlic bug—referred to in legislation as smooth bug) (Honey bug—referred to in legislation as shovel-nosed lobster)

Figure 3. Distinguishing features (head and body) of Balmain bug species (dorsal view) Balmain bugs Distinguishing Balmain bug features (mouthparts)

Dorsal surface covered with soft hairs Ibacus chacei (giving it a ‘velvety’ feel) (Garlic bug) Multiple incisions running across the mouthparts

Ibacus brucei (Honey bug) No incisions running across the Tail sometimes white mouthparts or pale in colour

Ibacus alticrenatus (Velvet bug—referred to in legislation as deepwater bug) Figure 3 (cont.). Distinguishing features (head and body) of Balmain bug species (dorsal view) Figure 4. Distinguishing features (mouthparts) of Balmain bug species Balmain bugs