SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f5304c3a98aa3234ab410775ed3dbcc9a4ca42033d1cf544519fed6f4306f3a7' 
  AND token = 'p2JVxHYAni6Y0cpVr+RB+K8+FpXvXLpNi422p3VYqrI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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