SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ebba55ddf569cedb68a459688568e59af7035efe141f14c1c88ea8e3c75b377' 
  AND token = 'N4L5QTsIzqxzWCvpTYHctx9r7SOX7yziRw0P3dB2yME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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