SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46c133cbff187f1b210209f2e77aaa399fdc7862785a92833bf2253e5cd7d734' 
  AND token = '2CTfXGhcJAR1FCh9kQyyEGfOd6uNwgjxl3qhsLnnJzc=' 
  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"
    }
  }
}