SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c93bb3157e1164c5828f0fcbfcfcb5fbe057e79496215bb688c57dbb77ca031' 
  AND token = 'GWDVznScyFmRflw7Phn9OkQctIIj60a+0SorZoU4GY0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}