SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e35ccd4c236a07d263fe5cff150ad73d6a38b71658f325edd44d9d24e51eef9' 
  AND token = 'nJ2zCtNnurZDyUFXyZOIYJ1yXO+PODNzebcausYOYZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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