Buprestidae of South Australia
( Jewel beetles )
by Peter J. Lang
Diphucrania semiobscura   (Kerremans, 1898)
subfamily  Agrilinae » tribe  Coraebini » subtribe  Cisseina
Diphucrania  species group: modesta
Diphucrania semiobscura   Adult images
Diphucrania semiobscura, PL0631A, PL0631B, male, from Acacia pycnantha, EP
Actual
size¹:
5.6 mm
×
2.2 mm
Measurements (mm)
malefemale
L15.4
4.6 – 5.95
n = 255.8
5.3 – 6.9
n = 16
L25.5
5.15 – 5.8
n = 75.7
5.4 – 6.1
n = 3
W2.2
1.9 – 2.4
n = 252.3
2.1 – 2.7
n = 16
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
Diphucrania semiobscura  Distinctive features

Based on Kerremans 1898, D. semiobscura differs from D. modesta in having the elytra purple (vs. purplish black) with light grey speckles (vs. traces of grey mottling), the antennae & tarsi 'obscure' [= dark] (vs. black), and the pronotum and scutellar region purple (vs. a shiny copper purple). Also the head is purple (vs. green), but this may simply be a result of different sexes being described. Structural differences apparent in the accounts of the two species seem slight and inconsequential: dimensions 5 x 1.8 mm (vs. 5 x 1.7 mm); pronotum sides fairly arched (vs. arched); pronotum base with median lobe barely indented (vs. a little indented); elytra with rugosities resembling scales (vs. with small transverse wrinkles).

Notes

This taxon is closely related to, and difficult to distinguish from, Diphucrania modesta (q.v.) which has an identical aedeagus; it may not warrant recognition as a distinct species. Its original description (as Cisseis semiobscura) by Kerremans 1898 was preceded on the same page by an adjacent protologue for C. modesta. Kerrremans introduced C. semiobscura stating that it had the appearance of C. modesta but was different in regard to certain details of structure and colouration, but did not elaborate further. The differences given under 'Distinctive features' above are derived from a comparison of his brief descriptions for the two species.

Analysis of preliminary DNA barcode sequences (mitochondrial CO-1) divided D. modesta and D. semiobscura samples into two tightly clustered and well separated sister groups: a sample of six individuals from the Mt Lofty Ranges (Belair, Mt Barker, Lobethal and Kapunda areas) and a sample of nine individuals from the Murray Mallee, southern Flinders Ranges and Eyre Peninsula (Monarto, Quorn, Kimba and Edilillie areas). The first group includes some 'typical' D. modesta forms with blackish elytra and coppery pronotum, and the latter some with more purplish elytra and pronotum that fit C. semiobscura. However, forms from the southern Mt Lofty Ranges (including some samples that grouped with typical C. modesta) often have the elytra dark coppery bronze to purplish rather than blackish. There is much variation, and it is not possible to find consistent colour or morphological differences corresponding to the two groups, nor any distinction based on adult host plants. A more detailed study with nuclear DNA may help resolve the taxonomy of this complex.

Distribution
SA Regions¹:  FREPMUYP
Australian States:  SAVIC
South Australia distribution
LegendP.J.Lang collection vouchered records
other private collection or museum specimens, or sightings
Satellite map
Terrain map
Enlarge map
Adult activity records for Diphucrania semiobscura  (total of 238 beetles)
7 24 51
22 2 16 2
66 28 7
12 1
Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun
Legend
live emerged adults, count > median value of 16 per quarter month
live emerged adults, count <= median value of 16
live non-emerged adults only, for that quarter month
12
number of active beetles for that quarter month
Adult host plants
beetles sites SA regions¹ family position on host plant
Acacia euthycarpa1026EP, MUF
Acacia calamifolia1008FR, EP, MUF
Acacia sp.205EPF
Acacia pycnantha121EPF
Leptospermum coriaceum21EPM
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 family
Code beetles % host plant taxa
F Fabaceae 234 99% 3
M Myrtaceae 2 1% 1
Position on adult host
positionbeetlessites
on flowering plant32
on foliage or non-flowering plant21115
on plant (unspecified)225
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.