SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dbfea8bbe1be6e889673d1cb77a4a77210cbc75ea619b4787bc0a767d69a130' 
  AND token = 'pW34xwZ/bEROdwVTroGmNm543bFOuqxa0HhVoShpSlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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