Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5de45a9fe9422b21d606fa7d75cdac64389d03e06ec80629fe1c56f21b0e584' 
  AND token = 'iRiJJ6N/yIBVhRzIcyjd2E3HEPlQmaHCLUp3HrzCUgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}