SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6a27883195eb5ca30e358c5dc68a32c8efd062f1f7343ab03cc9e763920e69ac' 
  AND token = 'dj5wZHfvgHBh8pJofZMRjNcwaocOtOE0ceiGf6gTi04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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