SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f43b83be300e447de98fcd1d34e426f606d8d2801dc8aff4aff8fa02675e949f' 
  AND token = '2nRYw7XYzr6gSeW/nMAShRgrYebqUYYYdGTo9Atfh70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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