SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6f25d3d6c173059be563118e5c494d77ebd0a75ae4ebef5b547a1e1449c11232' 
  AND token = 'UWZOuc0UNXr0LoFZyxSnDjMrdWUDkZkyhdvCwOa2+0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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