Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8776039c2c274e732e4fa74e8fbff13a69d7dbd2b4cff8e86460fbfb55f1a05' 
  AND token = 'dvlF/dxoBdqMcHvNo2qXv5siFi9RSLBM8sn5/yz8wlQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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