SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be801ff69cd3f02f1177be9ae210bcb5fa222c1be1350b79593151ae4230907b' 
  AND token = 'wlWEt3kTCFb7eml5NChDxQB/7WOw+FYr3AvcABCqYPs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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