World-renowned botanists Rod Saunders, 74, and his wife Rachel, 63, had recently finished recording a TV segment with the BBC when they were reportedly ambushed in a remote forest.

The trio accused of killing them are said to have put their bodies in sleeping bags and thrown them off a bridge into a crocodile-infested river, before going on a £37,000 spending spree with their credit cards.

In a resumed High Court trial in Durban, KwaZulu-Natal province, Sayfudeen Aslam Del Vecchio, 41, his wife Bibi Fatima Patel, 30, and their lodger Mussa Ahmed Jackson, 35, were accused of their brutal robbery and murder.

The Saunders’ bodies were found in the River Tugela near Eshowe in western South Africa days later, but it was months before they were identified by DNA tests.

A doctor told the court that examination of the bodies showed evidence of ‘scavenger activity’ adding: ‘The damage to the bodies suggest that something could have fed on them.

‘For example a crocodile due to the lost tissue on the arms, neck and chest. Once the bodies were pushed into the banks then dogs and rats could have fed on it.’

Post mortems carried out on the bodies revealed the couple died of blunt force trauma.

South African-born Rachel got British citizenship when she married Rod, a former nursery manager at the world-famous Kirstenbosch Botanical Gardens

Dr Rachel Saunders, a microbiologist, and Rodney, a horticulturist, had been married for 30 years, and spent half of each year collecting rare Gladioli seeds in remote South African mountains to ship around the world.

On February 4, 2018, they were joined in their search by a crew from the BBC show Gardeners’ World and presenter Nick Bailey, who interviewed the pair.

A selfie taken by Mr Bailey and shared on his Twitter account was the final picture taken of the Saunders while they were alive.

After returning from filming in the Drakensberg Mountains and leaving the camera crew, the couple headed for the Ngoye Forest.

The couple ran a mail order business called Silverhill Seeds to distribute their rare Gladioli seeds, and lectured around the world

It was within the forest that they were allegedly targeted by the three accused, who reportedly had messages on their phones suggesting the couple would make a ‘good hunt’.

The court was told: ‘Around February 10 the investigating officer received information that Rodney Saunders and his wife Dr Rachel Saunders had been kidnapped in the KwaZulu-Natal region.

‘It was established on February 13 that the defendants were drawing money from ATMs which amounted to theft of R734,000 (£37,000) and there was the robbery of their Toyota Land Cruiser and camping gear.

‘It is alleged that between February 10 and 15 at the Ngoye Forest the accused did unlawfully and intentionally kill Rachel Saunders and between the same dates did unlawfully and intentionally kill Rodney Saunders.’

The elite Hawks police squad had found a link between the cell phones belonging to Mr and Mrs Saunders and the cell phones of the suspects.

Isis pamphlets and flags were also found at their home.

The court heard: ‘On March 23 the third accused Jackson was arrested and he made a statement to the effect he was woken by Patel at their home on February 10 and told to meet Del Vecchio on the road.

‘Del Vecchio was in the Land Cruiser and Patel and Jackson followed to the Tugela River Bridge where they helped him remove the sleeping bags from the back and threw them with human bodies inside into the river.’

Married couple Del Vecchio and Patel and their lodger Jackson, who is Malawian, deny kidnap, murder, robbery and theft at Durban High Court.

The trial continues.