SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33afe9d0243f2e805e6262eb6d69ffec1b399accf02916824a9da0ea832db519' 
  AND token = 'yREKEiQduiduBz3NBKtcxGY6wmgWywg5UPwGjySnCPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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