.
Scarabaeoidea of Southern South America Links |
| |
|
|
|
| |
| .. |
Scarab Guide Links
(goes to the University of Nebraska
web site) |
.
Classification |
|
|
| ...... |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| ... |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| .. |
| ... |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| . |
| .. |
| . |
| . |
| . |
| . |
| . |
| . |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
|
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
|
|
| . |
.
Brachysternus olivaceus Philippi and Philippi, 1864
Brachysternus olivaceus Philippi and Philippi 1864:318. |
| |
|
Figure 31a-c. Form of the male genitalia in Brachysternus olivaceus (lateral view of
parameres and apex of phallobase, caudal view of parameres, and ventral view of ventral
and lateral sclerites). |
| |
|
Map showing the distribution of B. olivaceus. |
|
| |
...... |
|
Description. Length: 17.0-21.4 mm. Width: 7.7-10.5 mm at base of elytra. Color:
Dorsally dark shiny apple green to olivaceous shiny green, elytral margins metallic
brassy-green; clypeus tan with or without metallic green on disc; femora, tibiae, sternites,
and pygidium shiny testaceous; propygidium and tergites shiny brown. Head: Clypeal
apex rectangular with broadly rounded corners, not constricted at base; margins and apex
weakly reflexed (male) or weakly reflexed only at tip (female). Frons densely punctate;
punctures moderately large (base and sides) and moderate (disc) interspersed with minute
punctures, some setose; setae hair-like laterally (sparse, moderately long, tawny), thickened
posterior to eye (sparse, moderately long, white). Clypeus densely punctate (base)
to rugopunctate (mid-disc to apex) in male, rugopunctate in female; punctures moderately
large. Interocular width 2.8-3.3 transverse eye diameters (male) or 4.5-5.5 (female).
Terminal segment of maxillary palpus in dorsal view weakly impressed or flattened from
base to middle, segment subequal in length to segments 2-3. Antennal club slightly
longer than segments 1-7 (male) or subequal to segments 1-7 (female). Pronotum: Surface
with or without weakly impressed, median, longitudinal groove; disc moderately
punctate, moderately densely punctate laterally; punctures moderately large, some setose;
setae hair-like and thickened, moderately long and long, tawny, sparse. Basal bead complete
to just beyond posteriolateral angle. Elytron: Surface with 5-6 weakly impressed,
poorly defined, punctate, longitudinal striae between suture and humerus; punctures moderate
and small (mixed), sparse (disc) and moderately dense (margins and apex), some
setose; setae hair-like or thickened (moderately long to long, sparse, white). Intervals
with similar sculpturing. Humeral and apical umbone poorly developed. Epipleuron flat,
not expanded, marginal bead present; region from metacoxa to apex setose; setae thickened,
short to moderately long, dense, white. Sutural angle square. Propygidium: Posterior
margin with a fringe of setae; setae thickened, short, white. Supraspiracular ridge
indicated by weakly elevated line. Pygidium: Male: disc and middle apex with hair-like
setae (moderately long to long, moderately to sparsely dense, tawny to white) and punctures
(small, moderately dense to dense, some vertically confluent); margins with thickened
setae (moderately dense, white). Female: disc weakly impressed (not bituberculate),
punctate at apex (moderately dense) and at margins (moderately dense to dense); punctures
small, setose; setae hair-like, tawny, moderately long and long, sparse (at margins
and apex) and thickened, tawny or white, moderately long, moderately dense (at base
and margins). Venter: Sternum setose; moderately densely clothed with tawny, long,
hair-like setae; sternites moderately densely clothed with thickened, tawny, moderately
long setae (less dense in female). Prosternal keel triangular; apex projecting anteriorly
at about 458 with respect to ventral plane; apex produced to protrochanter, blunt or acute.
Mesometasternum with apex rounded, not produced. Apex of terminal sternite in female
moderately emarginated at middle. Legs: Larger claws of male thickened and
weakly bifurcate at subapex. Larger claws of female with ventral tooth. Tarsomere 5
with well developed ventromedial tooth, apex acute. Metatibia with inner and
outer edges straight, with 2 weak carinae; 1 at basal third (poorly developed), 1 at apical
third (moderately developed), carinae more developed in females; apical 1/5 weakly
divergent (more so in females). Male genitalia: Figure 31a-d. |
| |
|
|
Diagnosis. Brachysternus olivaceus is distinct from other species of
Brachysternus based on the following combination of characters: antennal club
slightly longer than segments 1-7 (male) or subequal to segments 1-7 (female),
pygidium lacking scale-like setae, large eyes (interocular width 2.8-3.3 transverse
eye diameters in males or 4.5-5.5 in females), and apex of the terminal
sternite in the female moderately emarginate.
The "B. riverae" morphotype of B. olivaceus could be confused with B.
spectabilis or B. prasinus. In specimens of this morphotype, the antennal club
is subequal to segments 1-7 (males and females), the interocular width is 3.5-
4.3 (male) to 5.2-5.6 (female), and the setae on the pygidium are more dense. However, the ventral sclerite of the male genitalia, the terminal sclerite of the
female, the supraspiracular ridge, and the form of the clypeal apex are characters
that are all consistent with B. olivaceus. Specimens of this morphotype
can be separated from B. spectabilis and B. prasinus based on the form of the
supraspiracular ridge (poorly developed in B. olivaceus; well developed in B.
spectabilis and B. prasinus), the form of the ventral sclerite in the male genitalia
in B. olivaceus contrasted with those of B. spectabilis, and the form of the terminal sclerite in the female (weakly emarginate in
B. olivaceus; deeply emarginate in B. prasinus and B. spectabilis), and the
more reflexed clypeal apex (apex weakly reflexed at tip in B. prasinus and B.
spectabilis). |
| |
|
|
Distribution (see map). Recorded from 500-2,300 m in elevation from Coquimbo
to Nuble, Chile. |
| . |
|
| |
Locality Data. 126 specimens examined from CASC, CMNC, CMNH,
FMNH, GASC, JMEC, KSUC, MNNC, PVGH, USNM, VMDM, ZMHB.
CHILE (121). ACONCAGUA (1): Fundo Talanquén. COQUIMBO (1): Valle
Elqui Alcohuaz. CURICO (59): Las Tablas, Los Niches. MAULE (1): Rio
Teno (40 km E Curico). O'HIGGINS (3): Las Nieves, Reserva Nacional Río
Cipreses. SANTIAGO (36): Alto de Cantillana, Buin, Cerro La Campana, Cerro
Roble Alto, El Monte, El Roble, Lo Aguirre, Maipú, Paine, Río Peuco (45
km S Santiago), Talagante. TALCA (8): Molina, Pencahue. VALPARAISO
(6): Limache, Valparaíso. NO DATA (6).
NO DATA (5). |
| |
|
| |
Temporal Data. January (2), September (3), October (79), November (27),
December (6). |
| |
|
| |
Remarks. Philippi and Philippi (1864) described B. olivaceus and B. chloris consecutively in their publication, but they did not discuss the differences
between the two species. When Philippi and Philippi named this species, they
were uncertain whether the species should be assigned to Brachysternus, Aulacopalpus,
or Tribostethes (=Aulacopalpus). They used the form of the claws
(which are split) to place the species in the genus Brachysternus. Based on
study of the type specimens of B. olivaceus and B. chloris, we determined that
these two taxa are conspecific.
Germain (1905) described two species that are conspecific with B. olivaceus:
B. herbaceus and B. riverae. Brachysternus herbaceus was described based on
one male specimen. Only the male genitalia, maxillae, and mentum were found
for this specimen. Based on our study of these parts, we determined that B.
herbaceus is conspecific with B. olivaceus. Brachysternus riverae was named
based on four specimens. Germain (1905) differentiated it from other species
based on color of the clypeus, color of the tibia and femora, and length of the
sternites. We have found that these characters are variable within the species.
In fact, two specimens from the original type series of B. riverae (the lectotype
and one paralectotype) are conspecific with B. olivaceus, and one paralectotype
is conspecific with B. prasinus. Only with a large number of specimens was
it possible to understand the breadth of intraspecific variation in B. olivaceus and to determine that the "B. riverae" morphotype is a member of this taxon.
Specimens of this morphotype share similarities with both B. prasinus and B.
spectabilis (see diagnosis). Based on several character states (see ‘Diagnosis'),
we determined that B. riverae is conspecific with B. olivaceus.
The invalid name "Brachysternus fulvescens Germain" is listed as a synonym
of B. chloris Philippi and Philippi in Machatschke (1972). Much confusion
has surrounded this name. The confusion began when Germain (1905: 473) transferred Bembegeneius fulvescens Solier to the genus Brachysternus.
He redescribed what he believed was Solier's concept of "fulvescens," but he
had not studied Solier's specimen of B. fulvescens. Ohaus (1909) believed that
Germain's "fulvescens" was simply a specimen of B. chloris that had been
discolored by preservation in alcohol, and was not Solier's "fulvescens."
Ohaus (1909) referred to Germain's concept as "Br. fulvescens Sol. sensu Ph.
Germain." Gutiérrez (1950) incorrectly listed "Brachysternus fulvescens Germain"
as a synonym of B. chloris, and this error was repeated by Machatschke
(1972). Bembegenius fulvescens Solier is now considered a junior synonym of
Aulacopalpus castaneus (Laporte) (see Smith 2002). |
| |
|
| |
Literature cited:
Germain, P. 1905. Apuntes entomológicos. Anales de la Universidad, Republica de Chile
115:449-506. ["1904"].
Gutiérrez, R. 1950. Notas sobre Scarabaeidae Chilenos (Coleoptera Lamellicornia). Arthropoda
1(2/4):267-278.
Machatschke, J. W. 1972. Scarabaeoidea: Melolonthidae, Rutelinae. Coleopterorum Catalogus
Supplementa 66(1):1-361.
Ohaus, F. 1909. Nachtrage und Berichtigungen zu meiner Revision der Brachysterniden
(Coleopt. lamellicornia). Stettiner Entomologische Zeitung 71:3-26. [1910].
Smith, A. B. T. 2002. Revision of the southern South American endemic genus Aulacopalpus Guérin-Méneville with phylogenetic and biogeographic analyses of the
subtribe Brachysternina (Coleoptera: Scarabaeidae: Rutelinae: Anoplognathini).
Coleopterists Bulletin 56:379-437. |
| |
|
| |
Excerpt from:
Jameson, M. L. and A. B. T. Smith. 2002. Revision of the South American genus Brachysternus Guérin-Ménville (Coleoptera: Ruteliinae: Anoplognathini: Brachysternina). Coleopterists Bulletin 56: 321-366. |
| |
|
