SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46b46db0c0b9e211477855784ace7654ca1eaf31f6838ce008e4b4f2aa50e1fa' 
  AND token = 'N0VAmmemteaXg5wY3EV9B6ZyVtXKcUxdaZiRRKtsyFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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