Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47a45d2c848325ad126c0a4eb246993c2cf63ad13b311e44dbfff341a26e5aca' 
  AND token = 'CbOYoQT+CcMzdjUo8isajn1WVEl9gA+ZZWdq0BCTGkY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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