SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '23477bbb235440b6a19470e84ff65db26a5ce7a4b7a992928eeb4084b6f2277d' 
  AND token = 'MztFqu5ZekKwDd///4mGG76F7C/b0++HX6NXyGjyse0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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