DISTRIBUTION:

Arsenura xanthopus (wingspan: males: 110-125mm; females: 115-140mm // forewing length: males: 62.8-63.8mm; females: 67.2mm) flies in
southeastern Brazil: Minas Gerais, Rio de Janeiro, Sao Paulo, Parana, Santa Catarina: Corupa; Rio Natal; and Rio Grande do Sul.

Arsenura xanthopus (- 22.117 976; - 46.681 662) Sao Joao da Boa Vista, Sao Paulo, Brazil,
January 28, 2007, courtesy of Ricardo Gomes.

Ezequiel Osvaldo Núñez Bustos sent me a paper in August 2015 which includes Arsenura xanthopus in northeastern Argentina: Misiones: Campo Ramón.

Ulf Drechsel confirms them in Paraguay.

Arsenura xanthopus female, Sanata Catarina, Brazil,
1990, courtesy/copyright of Hubert Mayer.

This moth is the same as A. alcmene Draudt, 1930.

Arsenura xanthopus male, Petropolis, RJ, Brazil, courtesy of Carlos G. C. Mielke. copyright

Arsenura xanthopus, Paraguay,
note yellow feet, courtesy/copyright Ulf Drechsel, id by Bill Oehlke.

I believe I have correctly identified the Ulf Drechsel specimen above, but I will ask for other opinions. Kirby Wolfe and Carlos Mielke have confirmed the identification.

The outward protrusion of the middle of the pm line is initiated in its upper reaches with a more rounded curve than in Arsenura orbignyana, where the outward protrusion is more angular than smooth. The forewing cell marking of xanthopus are also smaller (less wide), and usually with less contrasting brown than found in orbignyana, and the forewing apex is slightly produced in xanthopus, but scarely so in orbignyana.

I also note that on the hindwing, the basal and median areas of xanthopus are darker than in orbignyana, and the blueish-grey hindwing postmedian band in xanthopus is thinner and more continuous (in the males) than in orbignyana. In orbignyana this samee band is often divided into segments by the wing veins.

Larry Valentine, in Itanhand, southeastern Minas Gerais, Brazil, has had moths of both species appear at his light on the same date. Perhaps calling clock-time helps to keep these two species separated. Otherwise there may well be naturally occuring hybrids in the same area.

Orbignyana Groupe

Arsenura orbignyana

Arsenura paraorbignyana

Longitudinal line of forewing cell perpendicular to costa in both orbignyana and paraorbignyana. Hindwing marginal markings browner/larger in orbinyana; greyer/smaller in paraorbignyana Hindwing marginal area with more white in paraorbignyana

Arsenura angulatus

Arsenura xanthopus

Longitudinal line of fw cell not perpendicular to costa; cell mark lower-end angled more toward body Xanthopus has yellow legs, greyer, darker ground colour, practically devoid of white in in submarginal/marginal area; fw apex slightly produced

Arsenura xanthopus male, Itanhandu, Minas Gerais, Brazil,
note yellow feet, January 27, 2011, courtesy of Larry Valentine.

All of the features mentioned above for xanthopus are evident in the above image from Itanhandu.

The name xanthopus means "yellow foot". If you can handle specimens, look for yellow feet on xanthopus and much darker brown to black feet on orbignyana.

For comparison sake, I have included (below) an image of Arsenura angulatus from the same locale on the same date.

Arsenura agulatus male, Itanhandu, Minas Gerais, Brazil,
note dark feet, January 27, 2011, courtesy of Larry Valentine.

The distinguishing feature that stands out the most to me is the shape of the white post median band in its outward projection. It is more angular in angulata than in xanthopus. The other features are also present, but perhaps less noticeable. I have just noticed the much more obvious feature of the yellow feet!!!!

Perhaps even more important are the differences on the verso images (see below). I have not seen enough specimens to know if the differences are consistent, but the underside of the forewing of angulatus has dark triangluar flares, outwardly traced in "yellow-beige" in the marginal area. These markings seem to be absent or much less pronounced in xanthopus. Perhaps additional digital images will bear this out and provide a much simpler means of identification.

FLIGHT TIMES AND PREFERRED FOOD PLANTS:

Larry Valentine reports January 26, 2011, and February 20, 2013, flights in Itanhandu, southern Minas Gerais, Brazil. In Rio Grande do Sul specimens have been observed on the wing in January, February, September, October and December. Ricardo Gomes reports a late January flight in Sao Joao da Boa Vista, Sao Paulo, Brazil.

Arsenura xanthopus larvae feed on Luehea divaricata and Urena sinuata.

Arsenura xanthopus pair, courtesy of John Marchant.

ECLOSION, SCENTING AND MATING:

Arsenurini males use their antennae to seek out females which scent at night.

Arsenura xanthopus female, Petropolis, RJ, Brazil, courtesy of Carlos G. C. Mielke. copyright

Arsenura xanthopus courtesy of Alain Van Vyve

Arsenura xanthopus male (verso), Itanhandu, Minas Gerais, Brazil,
January 26, 2011, courtesy of Larry Valentine

Arsenura angulatus (verso), Itanhandu, Minas Gerais, Brazil,
November 23, 2009, courtesy of Larry Valentine, id by Bill Oehlke.

Arsenura xanthopus male (verso), Itanhandu, Minas Gerais, Brazil,
February 20, 2013, courtesy of Larry Valentine

Arsenura xanthopus male, Itanhandu, Minas Gerais, Brazil,
February 20, 2013, courtesy of Larry Valentine

EGGS, LARVAE AND PUPAE:

Mature, smooth-skinned larvae descend tree trunks to excavate and pupate in subterranean chambers. Image courtesy of Chris Conlan.

Arsenura xanthopus, fourth instar, Juiz de Fora, Minas Gerais, Brazil,
courtesy of D.M., id by Bill Oehlke.

Arsenura xanthopus, fifth instar, Juiz de Fora, Minas Gerais, Brazil,
courtesy of D.M., id by Bill Oehlke.

Arsenura xanthopus, fifth instar, Juiz de Fora, Minas Gerais, Brazil,
courtesy of D.M., id by Bill Oehlke.

Larval Food Plants

It is hoped that this alphabetical listing followed by the common name of the foodplant will prove useful. The list is not exhaustive. Experimenting with closely related foodplants is worthwhile.

Luehea divaricata....... Urena sinuata

Ka'a oveti Urena sinuata

The pronunciation of scientific names is troublesome for many. The "suggestion" at the top of the page is merely a suggestion. It is based on commonly accepted English pronunciation of Greek names and/or some fairly well accepted "rules" for latinized scientific names.

The suggested pronunciations, on this page and on other pages, are primarily put forward to assist those who hear with internal ears as they read.

There are many collectors from different countries whose intonations and accents would be different.

Some of the early describers/namers chose genus and species names indicating some character of the insect, but more often, they simply chose names from Greek or Roman mythology or history.

Those species names which end in "ensis" indicate a specimen locale, and those which end in "i", pronounced "eye", honour a contempory friend/collector/etc.

I do not know the source of the genus name "Arsenura" chosen by Duncan in 1841.

The species name "xanthopus" means "yellow foot".

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