SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e06ee68afdeaa3245ed3816bc49156ccb51e433fc965cabffd001dc0bcc2d262' 
  AND token = 'x+SkS2VZFbnEqmOgzaPgvzt9fDFSAXIhNHqgLxaFowc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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