Leucauge White, 1841

Dimitrov, Dimitar & Hormiga, Gustavo, 2010, Mr. Darwin’s mysterious spider: on the type species of the genus Leucauge White, 1841 (Tetragnathidae, Araneae), Zootaxa 2396, pp. 19-36 : 24

Genus Leucauge White, 1841

Type species (by monotypy) Linyphia (Leucauge) argyrobapta White, 1841 , a junior synonym of Epeira venusta Walckenaer, 1841

In his field notes Darwin suggested the new genus name Leucauge for argyrobapta (see Keynes, 2000), but nevertheless White (1841) described argyrobapta as a species of Linyphia and treated Leucauge as a subgenus, not as a new genus. This should be hardly surprising given that in his paper White (1841: 471) explicitly expressed reluctance to erect new genera:

“I describe them without any systematic order, but having necessarily numbered each species, intend afterwards giving a classified index: the descriptions are in many instances prolix, and I have in most cases given the generic character of each species. I have done this because, at present, I am unwilling to propose new names if I can possibly refer the species I describe to any of ties established genera.”

There is no hint in Darwin’s field book suggesting that argyrobapta had close affinities with Linyphia . In fact, Darwin’s entry (page 38 of this particular field book, as transcribed in Keynes, 2000) starts with the following text: “Spider, orbilates [orbitéles]; closely allied to Epeira ( Leucauge . [illeg.])”. Thus the generic placement in Linyphia must be entirely attributed to White. Although Waterhouse’s (1902:198) Index Zoologicus provides the first use of Leucauge as a genus name, the first arachnologists to use Darwin’s name at the genus rank were F. O. P.- Cambridge (1902a, 1903) and E. Simon (1903). In one of his papers on the type species of the genera of Araneae, Cambridge (1902b: 16) explicitly discusses the rank of Leucauge and quite openly expresses his dislike for Darwin’s new name:

“No one that has ever been in a tropical Brazilian forest will hesitate one moment in recognizing this as a species of the Argyroepeira group of Emerton.

One feels sorry at the necessity of sacrificing so beautiful a name for the ugly one Leucauge proposed by Darwin, but priority lies with the latter.”

Cameron (2005:302) deciphered the etymology of Leucauge (which means “with a bright gleam”, in reference to the characteristic silvery guanine abdominal marks) and pointed out how Bonnet (1957) also grumbled about the replacement of the more recent genus name Argyroepeira Emerton, 1884 by the older one Leucauge after having been forgotten for sixty years. We join Professor Cameron (2005:302) in rejoicing the preservation of “the only spider name which can be attributed to Charles Darwin.”