SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b830c0c87fe874f64bfa282b45a3e6a5410ee53abe43b888c83b028f4a2fe281' 
  AND token = 'AmYQ/GyTxoZff4aAqozzkJ1LVErsXmUm0i7M3JsDJZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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