Catiuscia Machado is allegedly murdered by her boyfriend in the bathtub at their Chiswick, inner western Sydney apartment

The boyfriend of a special education teacher whose body was found in the bathtub of their downtown apartment has been charged with murder.

Diogo De Oliveira, 40, is accused of killing Catiuscia Machado during a domestic incident on Saturday night at their Chiswick unit in Sydney’s west.

Police allege De Oliveira, 40, punched Ms Machado, causing her to fall into the water-filled bathtub where she died.

The Brazilian teacher, believed to be in her 40s, had only recently arrived in Australia. Police are currently contacting her relatives in her home country.

De Oliveira is said to have called a friend in the aftermath of the death, who then called the police and raised the alarm.

Officers called to the house arrested De Oliveira at the scene and he was charged with murder at Burwood police station.

He appeared at Burwood Local Court on Monday and did not apply for bail. A post-mortem examination is underway to determine the cause of death.