SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f95165aee3d87abb7fb78f830587e2ab6b83a040e3a2438cc4baf91a643dc06' 
  AND token = 'z0GCzBmTobjszNS7yNLYFtLoFwCn6XEJHF/hXQRz+qw=' 
  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"
    }
  }
}