SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a0a47bacb9ae0ddb50e019c8d827f4dcc58f257481b95b95835b16704962fff2' 
  AND token = 'sztN7ZUDXPQd+k8iGP7/ooWlCU+GQfHwKw7RFuCTsYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}