The Golden Tortoise Beetle – Natures Gold

Introduction

Gardeners often notice the “goldbugs” or “gold tortoise beetles, which feed on Convolvulaceae plants. These insects can sometimes be quite destructive to plants, but they are mostly just curious.

Distribution and Habitat

The golden tortoise is a widespread beetle that can be found in Eastern North America. It is also found west to Texas and Iowa. It is one of three species found in Florida.

Description and Life Cycle

This species is not well-known for its biological importance, which may be due to the fact that very little information is available. There is usually only one generation per year in the northern states. New Jersey beetles appear first in May or June.

They feed on weeds and then deposit eggs shortly thereafter. In July, a new population of adult beetles is visible. They feed briefly until they enter diapause, then resume their normal activities in the spring.

The average time it takes to develop from an egg into an adult is 40 days. Florida does not know the number of years between generations.

Adults

Adult beetles have a distinctive feature: the margins of their prothoraxes and elytra’s are expanded. This expands the ability to conceal the head and other appendages. These expanded margins appear almost transparent and aren’t pigmented.

They are small and measure 5.0 to 7.0 mm in size. Although the beetles’ colours can vary, they are all orange-coloured and often called “goldbugs”.

Eggs

The eggs are attached to the undersides of leaves or on stems and are white in colour. The eggs are flattened and oval. They are only 1 mm long and hatch in 5-10 days. The eggs are placed in groups of 20 to 30 eggs.

Larvae

The larvae are flattened, broad and decorated with branched spines. They have a short, thick thoracic leg. The larva’s colour is yellowish-reddish-brown. Three larval instars are available.

The larvae have a habit of carrying cast skins and faecal matter attached to spines at the posterior end of the body.

This structure is called an “analfork”. The anal fork can be moved and is used to keep predation away by holding the debris on the back of their bodies. Larvae mature between 14 and 21 days.

The anal end of mature larvae attaches to leaves, and they pupate. The pupae are brownish-coloured. The pupae have spines, just like the larvae. The pupa may still have faecal matter and other debris from the larval stage. The length of the pupae is 5-8 mm. The pupal stage lasts seven to fourteen days.

Host plants

The golden tortoise insect is often associated with sweet potatoes and other related species, such as morning glory, Ipomoea, and Convolvulus.

The Convolvulaceae family includes bindweeds and morning glory, as well as sweet potatoes. The larvae and adults both eat the foliage.

Damage

Both adults and larvae feed on leaves. A common form of injury is the formation of small- to medium-sized, irregular holes. Both stages live on the lower surface of the leaves, but they eat through it completely. Tortoise beetles are rarely considered to be harmful.

Natural Enemies

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The golden tortoise wasp beetle is being attacked by the wasp parasitoid Tetrastichus Cassidus Burks (Hymenoptera, Eulophidae).

Numerous ladybird beetle predators, such as Coccinella species, have been known to cause mortality, especially among larvae. and Coleomegilla (Coleoptera, Coccinellidae), especially those with piercing-sucking jaw parts like damsel bugs (Hemiptera: Nabidae), shield insects (Hemiptera: Pentatomidae), or assassin bugs. (Hemiptera: Reduviidae).

Although the “shield” that is carried by larvae can be effective against small predators and large predators with long, piercing-sucking jaws is not enough to deter them.

Management

Although it is possible to control larvae and adults by applying insecticides to the leaves, this action is seldom warranted.