SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '53b780cbc792a4e0b647a515dd1094336a9cdfa9f48495c7bd706d4133e8ee3f' 
  AND token = 'DvkIb41/qS15/Ia2IcJAKhFjwvdLXx1CeJFHy1P2pTQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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