Buprestidae of South Australia
( Jewel beetles )
by Peter J. Lang
Melobasis obscurella   Thomson, 1879
subfamily  Buprestinae » tribe  Melobasini » subtribe  Melobasina
Melobasis  species group: obscurella
Melobasis obscurella   Adult images (last updated: 29 Mar 2020)
Melobasis obscurella, PL0722, female, on Exocarpos cupressiformis, NL, Niblet Gap, 4 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL0722, female, shown on Acacia pycnantha, NL, Niblet Gap, 4 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL0723, female, on Acacia pycnantha, MU, 10.5 km NNW Robertstown, 6 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL1527, male, on Acacia euthycarpa, EP, 6.6 km SSW Carpie Puntha Hill summit, Heggaton CP, 2 Oct 2010, 9.7 × 3.5 mm Melobasis obscurella, PL2324C, male, on Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012 Melobasis obscurella, PL2322A, male, from Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012, 8.8 × 3.2 mm Melobasis obscurella, PL0722, female, NL, Niblet Gap, 4 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL0724, female, from Acacia calamifolia, MU, 10.7 km NNW Robertstown, 6 Oct 2009, 8.6 × 3.1 mm Melobasis obscurella, PL1033, female, from Acacia wattsiana, NL, 0.45 km ESE Webb Gap, 2 Dec 2009, 9.8 × 3.5 mm Melobasis obscurella, PL2324C, male, on Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012 Melobasis obscurella, PL2322A, male, on Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012, 8.8 × 3.2 mm Melobasis obscurella, PL2323A, male, on Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012, 8.9 × 3.2 mm Melobasis obscurella, PL2323A, male, on Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012, 8.9 × 3.2 mm Melobasis obscurella, PL2323A, male, on Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012, 8.9 × 3.2 mm Melobasis obscurella, PL2324C, male, on Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012 Melobasis obscurella, PL0722, female, shown Acacia pycnantha, NL, Niblet Gap, 4 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL0722, female, shown Acacia pycnantha, NL, Niblet Gap, 4 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL0722, female, feeding on Acacia pycnantha phyllode gland, MU, Niblet Gap, 4 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL0722, female, feeding on Acacia pycnantha phyllode gland, MU, Niblet Gap, 4 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL0723, female, on Acacia pycnantha, feeding from gland, MU, 10.5 km NNW Robertstown, 6 Oct 2009, 10.3 × 3.7 mm Melobasis obscurella, PL1528A, male, on Acacia euthycarpa, EP, 6.6 km SSW Carpie Puntha Hill summit, Heggaton CP, 2 Oct 2010, 8.2 × 3.0 mm Melobasis obscurella, PL1528A, male, on Acacia euthycarpa, EP, 6.6 km SSW Carpie Puntha Hill summit, Heggaton CP, 2 Oct 2010, 8.2 × 3.0 mm Melobasis obscurella, PL2323, adult host plant, Acacia spilleriana, MU, 10.8 km NNW Robertstown, 3 Oct 2012
Actual
size¹:
8.9 mm
×
3.2 mm
Measurements (mm)
malefemale
L18.4
7.65 – 9.7
 n = 109.6
8.55 – 10.7
 n = 7
L210.5
 n = 1
W3.0
2.75 – 3.45
 n = 103.5
3.05 – 3.9
 n = 7
Legend  L1length from clypeus/frons to elytral apex (mean, range, sample size)
L2length from anterior of edge of eyes to elytral apex
Wmaximum width with elytra fully closed
Melobasis obscurella  Distinctive features

Females often superficially resemble M. thoracica but are readily distinguished by the posterior margin of the pronotum being +/- linear rather than biangulate.

Notes

An early-emerging species, frequently associated with flowering Acacia species.

Distribution
SA Regions¹:  FR,  EP,  NL,  MU,  YP,  SL
Australian States:  WA,  NT,  SA,  TAS,  VIC,  NSW
South Australian occurrences
LegendP.J.Lang collection vouchered records
other private collection or museum specimens, or sightings
Satellite map
Terrain map
Enlarge map
Adult activity records for Melobasis obscurella  (total actual records: 79 beetles)
5
5 5 7
38 12 2
4
1
Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun
Legend
9
number of active beetles, actually recorded in that quarter-month
actual count > 5 (median)
actual count <= 5 (median)
Adult host plants
beetles sites SA regions¹ family position on host plant
Acacia spilleriana201MUF
Acacia calamifolia175FR, MUF
Acacia sp.145EP, NL, MUF
Acacia pycnantha73FR, NL, MU, SLF
Acacia rigens73EP, MUF
Acacia wattsiana51NLF
Acacia brachybotrya41NLF
Acacia euthycarpa31EPF
Acacia retinodes11SLF
Exocarpos cupressiformis11NLS
Legendbeetlescount of beetles collected from, or sighted on, host plant taxon
sitescount of major sites (unique 10 km grid cells +/- some distinct approximate localities)
Plant names in green are hyperlinked to a matching host species page with plant photos.
Plant family
Code beetles % host plant taxa
F Fabaceae 78 99% 8
S Santalaceae 1 1% 1
Position on adult host
positionbeetlessites
on flower(s)42
on flowering plant377
on foliage or non-flowering plant258
on plant (unspecified)135
Lure affinity
colour beetles sites SA regions¹
yellow11EP
Larval host plant
records sites SA regions¹ family adult ex billet
Acacia spilleriana11MUF1
Legendrecordscount of breeding adults, pupae and larvae
sitescount of major sites (unique 10 km grid cells +/- some distinct approximate localities)
adultlive = extracted alive;   dead = extracted dead as intact or fragmentary remains;   ex billet = reared and emerged from stored sections of host;   ex pupa = reared from sampled pupa
pupaextracted pupa;   pupa ex larva = reared pupa from larva
larvaextracted larva (any stage including prepupa)
gall (only)hatched or unhatched gall identified by form and position rather than contents
Plant names in green are hyperlinked to a matching host species page with plant photos.
Plant family
Code records % host plant taxa
F Fabaceae 1 100% 1
Position in larval host
positionrecordssitesadult ex billet
dead stem111
Host plant notes

I reared a single adult female from billets cut from dead branches of Acacia spilleriana, one of its adult host plant species.

¹ LegendregionsSA State Herbarium regions (map)
EA: Eastern, EP: Eyre Peninsula, FR: Flinders Ranges, GT: Gairdner-Torrens, KI: Kangaroo Island, LE: Lake Eyre, MU: Murray, NL: Northern Lofty, NU: Nullarbor, NW: North-Western, SE: South-Eastern, SL: Southern Lofty, YP: Yorke Peninsula
sizeThe ellipse is the correct size when printed, indicative on a desktop screen, and likely to be wrong on a mobile device.