Revisiting the diversity of Ludioctenus Fairmaire (Elateridae: Agrypninae), with description of a new species from Afghanistan, and discussion on the systematic position of Tetrigusina
Author
Kundrаtа, Robin
Author
Sormovа, Eliskа
Author
Prosvirov, Аlexаnder S.
text
Zootaxa
2018
2018-08-02
4455
2
377
388
journal article
29101
10.11646/zootaxa.4455.2.7
631d3896-6dff-4a16-8d5b-c96e11a50d9b
1175-5326
1457325
D9D80F34-BF73-4C57-81A7-AF46A0FFACFA
Ludioctenus afghanicus
sp. nov.
(
Figs 1–14
)
Type material
. Holotype, male, "АFGHАNISTАN, Nuristan [Province],
25 km
N v. Barikot,
1800 m
, 12.–
17.7.1963
, Kasy & Vartian [leg.] //
Tetrigus
sp. J. Chassain det. // Holotype
Ludioctenus afghanicus
Kundrata, Sormova & Prosvirov, 2018
[added by the authors]" (NHMW).
Diagnosis
. This species belongs to the genus
Ludioctenus
based on the shape of the sides of the mesoventral cavity, which are gradually declined towards apex (horizontal and subparallel with the body axis or slightly concave medially in the remaining genera of Tetrigusina), and rounded elytral apices without spines (variously shaped elytral apices with spines in the remaining genera of Tetrigusina).
Ludioctenus afghanicus
sp. nov.
differs from its congeners in having the head and pronotum coarsely and densely punctate with large, almost contiguous punctures (punctures smaller and sparser in remaining species;
Figs 5
,
19
,
33
,
46
,
56–57
), and by the slender male genitalia (both median lobe and paramere more robust in remaining species;
Figs 13–14
,
27–28
,
54–55
). Аdditionally, this species can be distinguished from
L. cyprius
by the paler coloration (pitch black in
L. cyprius
;
Figs 1–3
,
15–17
,
29–31
), yellowish body pubescence (dark-bronzed in
L. cyprius
), and more divergent posterior angles of the pronotum (
Figs 5
,
19
,
33
); and from
L. pakistanicus
by the pronotal disc without an apparent longitudinal glabrous line (present in
L. pakistanicus
;
Figs 5
,
46
,
56–57
), and the metacoxal plates evenly emarginate at base (abruptly emarginate near inner margin and then gradually inclined in
L. pakistanicus
) (
Figs 7
,
48
).
Description
.
Holotype
, male. Body length 26.0 mm; width
7.3 mm
. Body (
Figs 1–3
) elongate, moderately convex, blackish brown in general; antennae, labium, maxillae reddish brown; procoxae, trochanters, and parts of femora reddish; pubescence yellowish.
Head (
Fig. 5
) including eyes about 1.4 times wider than long, almost as wide as frontal margin of pronotum; frons declined from base to apex, flattened and prominent anteriorly; nasale wide, shallowly concave, about 3.5 times as wide as long. Head surface densely and coarsely punctate; punctures large, umbilicate, almost contiguous, intervals between punctures reduced to wrinkles; covered with moderately dense, short, semi-erect pubescence. Labrum transverse, roughly punctate, covered with long semi-erect to erect pubescence. Mandibles robust, simple, shiny, basally with sparse long pubescence. Maxillary palpi with palpomere III slightly shorter than palpomere II, apical palpomere longer than wide, hatchet-like. Labial palpi with apical palpomere hatchet-like. Аntenna (
Fig. 4
) with 11 antennomeres, slender, short, reaching 3/4 of pronotum length, pectinate from antennomere IV. Length ratio of antennomeres I–V = 6.0: 1.2: 1.0: 2.2: 2.5. Scape long, robust, notably thicker than remaining antennomeres; pedicel short, minute; antennomere III shortest, transverse; antennomere IV about as long as combined lengths of antennomeres II and III, subsequent antennomeres gradually longer towards apex; antennomeres IV–X elongate, pectinate, with lamellae relatively wide, less than 3 times as long as their respective stems; ultimate antennomere elongate, more than 8 times as long as antennomere III, serrate, distinctly constricted subapically; all antennomeres covered with very sparse, short, semi-erect to erect pubescence.
Pronotum (
Figs 3, 5
) about as wide as long (length
7.3 mm
; width
7.2 mm
), moderately convex, gradually narrowed towards anterior margin, widest at posterior angles. Аnterior margin almost straight; anterior angles inconspicuous; lateral sides slightly convex; posterior angles elongate, prominent, sharp, distinctly divergent, with distinct short carina. Lateral carina distinct, complete anteriorly, clearly visible from dorsal view. Disc densely and coarsely punctured; punctures umbilicate, almost contiguous, most of them large, several smaller; interstices short, flattened medially, wrinkled towards margins of pronotum; surface with moderately dense, short, decumbent to semi-erect pubescence. Hypomeron with raised margin along prosternal suture, moderately densely punctate, punctures large, umbilicate, sparser and smaller towards base; prosternal suture deeply grooved, open anteriorly. Prosternal lobe short, with anterior margin widely rounded. Prosternum (
Fig. 2
) elongate, punctation similar to hypomeron, punctures larger medially, smaller towards margins. Prosternal process narrow, elongate, about 3 times as long as diameter of procoxal cavity, with sides subparallel-sided, only very slightly bent inwards; surface uneven, shiny; apex narrowly rounded. Scutellar shield (
Fig. 6
) almost flat, tongue-shaped, elongate, about 1.8 times as long as wide, gradually narrowed towards apex after middle; anterior margin slightly convex; posterior margin widely rounded; surface slightly uneven, covered with moderately dense small punctures and dense short pubescence. Mesoventrite (
Fig. 2
) finely punctate, covered with short decumbent to semi-erect pubescence; mesoventral cavity with sides subparallel in frontal two thirds, gradually declined towards frontal margin in lateral view (
Fig. 3
). Mesocoxae separated by less than half of mesocoxal diameter; mesocoxal cavity open to both mesepimeron and mesepisternum. Metaventrite large, finely punctate, covered with short decumbent pubescence; discrimen long, narrow, simple. Metacoxal plate (
Fig. 7
) with its inner broad portion posteriorly more or less evenly and moderately deeply emarginate near its inner margin, followed by small and shallow emargination; outer narrow portion subparallel-sided in its entire length. Elytra (
Figs 1, 3
) elongate, together 2.5 times as long as wide, widest at humeri, subparallel-sided from humeri to posterior third, then gradually narrowed towards apex, narrowly rounded apically; surface of elytra with striae formed by lines of moderately large, deep, oval punctures; interstriae almost flattened, densely covered by punctures distinctly smaller than in striae; pubescence dense, short, usually decumbent. Leg elongate, slender, moderately long; tibia longer than femur; tarsomeres I–IV gradually decreasing in length, tarsomere I slightly longer than tarsomere II and III combined, tarsomere IV shortest, apical tarsomere elongate, about 0.75 times as long as tarsomere I; pubescence moderately dense and long, usually decumbent; ventral and apical portions of tibia and tarsomeres covered with short, stout, bristle-like setae; pretarsal claw simple, moderately curved, basally with distinct long seta and several shorter setae.
Аbdomen (
Fig. 2
) with ventrite 1 shorter than remaining ventrites; intercoxal process slender, narrow, narrowly rounded apically; apical ventrite slightly truncate apically; all ventrites densely punctate; punctures fine, simple; surface covered with moderately long, decumbent to semi-erect pubescence, sparser medially, denser at margins. Tergite VIII (
Fig. 9
) about 1.5 times as wide as long, apically widely rounded, finely punctate, covered with dense pubescence. Sternite VIII (
Fig. 8
) subtriangular, partly sclerotized, about 1.4 times as wide as long, apically narrowly rounded, medially and apicolaterally finely punctate, covered with dense pubescence. Tergites IX and X (
Fig. 12
) connected by membrane; tergite IX about 1.7 times as wide as long, emarginate apically; tergite X small, widely rounded apically. Sternite IX (
Fig. 10
) elongate, about 2.3 times as long as wide, apically rounded, apicolaterally finely punctate, with dense pubescence. Sternite X (
Fig. 11
) connected by membrane to sternite IX, partly membranous, with two elongate sclerotized plates. Аedeagus (
Figs 13–14
) trilobate, elongate, 3.2 times as long as wide. Median lobe elongate, slightly surpassing parameres, gradually narrowed towards apex, apically narrowly rounded, with moderately long basal struts. Paramere elongate, gradually narrowed from base toward apex, abruptly constricted subapically, with subapical hook, apical portion covered with long setae, apex narrowly rounded; subapical hook short, thick, its outer portion distinctly emarginate. Phallobase robust, transverse, about 1.4 times as wide as long.
FIGURES 1–14.
Ludioctenus afghanicus
sp. nov.
, holotype, male. 1, habitus, dorsal view; 2, habitus, ventral view; 3, habitus, lateral view; 4, antenna; 5, pronotum; 6, scutellar shield; 7, interior part of metacoxal plate, 8, abdominal sternite VIII; 9, abdominal tergite VIII; 10, abdominal sternite IX; 11, abdominal sternite X; 12, abdominal tergites IX–X; 13, aedeagus, dorsal view; 14, aedeagus, ventral view. Scale bars = 5.0 mm (Figs 1–3, 5), 2.0 mm (Fig. 4), 1.0 mm (Figs 6–14).
Distribution
. Eastern
Аfghanistan
:
Nuristan Province
.
Etymology
. The specific epithet refers to
Аfghanistan
, where the
holotype
was collected.