Roboris

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Ena Marklund

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Aug 3, 2024, 4:56:19 PM8/3/24

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Lachninae : Lachnini : Lachnus roboris : spp. list Lachnus roborisVariegated oak aphidOn this page: Identification & DistributionBiology & Ecology:Life cycleAnt attendanceNatural enemiesOther aphids on the same hostIdentification & Distribution:Lachnus roboris apterae are shining blackish brown. The antennae are quite short - for apterae 0.4-0.5 times the body length. The dorsum has only a few short hairs (cf. Lachnus longirostris & Lachnus pallipes which have the abdominal dorsum densely haired with long, fine-pointed hairs). There are two conical tubercles on the front of the mesosternum. The siphuncular cones are large and dark, with their maximum diameter exceeding the length of the second hind tarsal segment (cf. Lachnus pallipes & Lachnus longirostris which have smaller paler siphuncular cones with their maximum diameter less than the length of the second hind tarsal segment). The body length of an adult Lachnus roboris aptera is 2.5-5.5 mm.

Habitat:
Laeosopis roboris inhabits mostly wet places in river valleys dominated by light woods or just individual trees. In Andalusia, I met Laeosopis roboris very abundant in the Sierra de Cazorla at lower altitudes with streams and seasonally dry pastures with Brenthis hecate. In Provence, I observed Laeosopis roboris in a river valley near Auriol along with Brenthis daphne and Satyrium esculi.

Life cycle:
The eggs are deposited on branches, and the caterpillar hatch in spring. It is resting on branches or on the trunk, where it is well camouflaged. The moths fly in June and July. I met large butterfly concentrations at Thyme (Thymus mastichina).

Until 2009 I had only found it at one site in Var where the flight period was end-May to mid-June although I found that most specimens were showing serious signs of wear by 7 June.It was found there regularly every year although in limited numbers. However, in late June 2008 I visited a site I had visited frequently in early spring and found roboris present, nowhere near water and no obvious Ash trees in the vicinity. A similar visit in 2009 produced roboris in large numbers, where fifty or more could have been counted nectaring in the afternoon, and that may have only been the tip of the iceberg. In 2012 I found it at three more locations, so it may be more widespread than originally thought; it is somewhat sedentary and probably under-recorded.

In this study, Lachnus roboris Linnaeus (Hemiptera: Aphididae) on the samples of chestnut trees was recorded for the first time in the Ondokuz Mayis University Campus in Samsun and were examined morphologically in laboratory. Photographs of various body parts of apterous viviparous females of L. roboris were taken and morphological measurements of 40 apterous viviparous females and 120 eggs were also performed. In the study, egg length, body length, body width, antenna (left), (right),and corniculus of the pest were determined to be 1.70 mm, 4.66 mm, 2.23 mm, 2.23 mm, 1.99 mm and 471.57 m, respectively. In addition, PT/ BASE ratio of Ant.VI was found as 0.45.