Revision of Mahea Distant, 1909, with a review of the Acanthosomatidae (Insecta: Heteroptera) of Madagascar and Seychelles
Author
Kment, Petr
) &) Department of Entomology, National Museum, Kunratice 1, CZ- 148 00 Praha 4, Czech Republic; e-mail: sigara @ post. cz &) &) Department of Zoology, Faculty of Science, Charles University, Viničná 7, CZ- 128 44 Praha 2, Czech Republic
text
Acta Entomologica Musei Nationalis Pragae
2005
suppl.
2005-12-31
45
21
50
journal article
8626
10.5281/zenodo.4476396
f638455f-2539-4bb0-816f-bafbc0b7c1ac
ISSN0374-1036
4476396
Mahea sexualis
Distant, 1909
(
Figs. 1-7, 31
, 40-41)
Mahea sexualis
Distant, 1909: 32-33
, pl. 4 (description, figure of female).
Mahea sexualis
:
KUMAR (1974)
: 44
(taxonomy, invalid
lectotype
designation).
Type
locality.
Seychelles
,
Mahé
.
Type material.
LECTOTYPE
: ♁, ‘
Seychelles
/ Mahe / H
P.T.
1906 [p] //
Mahea
/ sexualis / Dist. [hw] // University Museum of / Zoology, CAMBRIDGE [p] //
LECTOTYPUS
/
MAHEA
/ SEXUALIS /
Distant, 1909
/ des. P. KMENT 2005’ [p, red label] (
CUMZ
), here designated. The
lectotype
is glued onto the tip of a pentagonal piece of card, with the pygophore removed and mounted on the same piece of card. The original piece of card is pinned under the new one. Antennomeres 3 and 4 of both antennae, right middle and hind legs, and all tarsi from left legs of the
lectotype
are missing.
PARALECTOTYPES
: 1 ♁ and
1 ♀
, ‘
Seychelles
/
Mahe
/ H P.T. 1906 [p] // Distant Coll. / 1911-383 [p] // SYN- / TYPE [p, white circle with blue margin] //
PARALECTOTYPUS
/
MAHEA
/ SEXUALIS /
Distant, 1909
/ des. P. KMENT 2005’ [p, red label] (
BMNH
). The male
paralectotype
is pinned, its antennomeres 2-4 (left) and 3-4 (right), all left legs (except hind femur), right hind leg, apical part of scutellum and pygophore missing, and it has a large pinpoint in the scutellum. The female
paralectotype
is mounted on the tip of a pentagonal piece of card, with one separate leg glued on the same piece of card. Rest of legs and antennae are missing, right pronotal spine broken, and abdomen ruptured ventrally on the left side.
Redescription.
Body slightly shining; basic colour ochraceous, with coarse dark punctures.
Male (
lectotype
) (Fig. 40). Length
7.5 mm
, width of pronotum between humeral angles
4 mm
. Head (
Fig. 1
) pale ochraceous with coarse brown punctures forming more or less apparent rows (two rows on each mandibular plate, posteriorly coalescent, forming a figure resembling an 8 next to each eye; two rows on clypeus, partly coalescent medially, reaching to posterior margin of head, on frons surrounded by two rows forming an incomplete circle). Head shorter than wide (1: 1.35), its width about half that of pronotum between humeral angles (1: 2.08). Mandibular plates basally almost parallel, suddenly curved inwards apically, not meeting; apex of clypeus free (
Fig. 1
). Eyes large, ochraceous; ocelli ochraceous, situated behind eyes, near anterior pronotal margin. Each antenniferous tubercle with black longitudinal spot laterally; antennae castaneous; antennomere 1 pale, basally ochraceous; antennomere 2 with erect pubescence, hairs slightly shorter than diameter of antennomere; length of antennomeres: 1 –
0.4 mm
,
2 – 2.3 mm
(ratio 1: 5.75). Head ventrally pale ochraceous, without punctures; apex of rostrum blackened, reaching middle of sternum 4.
Pronotum ochraceous with thick brown punctures; punctures on posterior half more dense than on anterior half; pronotal spines and narrow median line ochraceous; anterior margin concave; antero-lateral margins widening posteriad; humeral angles prominent, each abruptly produced into long, narrow spine directed laterad (
Figs. 2-3
). Scutellum triangular, ochraceous, anterior part medially brownish, with brown punctures; anterior part arched, sloping posteriad; posterior part flat, apex blackened, triangular. Hemelytra ochraceous with brown punctures; suture between corium and membrane brown; membrane slightly brownish, translucent, slightly surpassing postero-lateral angles of sternum 7.
Figs. 1-5.
Mahea sexualis
Distant, 1909
. 1 – head, dorsal view; 2 – pronotum, dorsal view; 3 – pronotum, posterior view; 4 – abdomen of male (lectotype), ventral view; 5 – abdomen of female (paralectotype), ventral view.
Figs. 6-7.
Mahea sexualis
Distant, 1909
. Pygophore (lectotype). 6 – posterior view; 7 – ventral view. Scale bars 0.5 mm.
Thorax ventrally with coarse brown punctures, which are more sparse on metapleura; peritreme ochraceous. Metapleura swollen, its postero-lateral corners visible in dorsal view.
Legs ochraceous, apices of tibiae and tarsomeres 2 slightly blackened; hind femur and tibia with inner margin granulated, femur slightly swollen and curved inwards, tibia straight. Abdomen with only connexival spines visible from above; ventrally ochraceous, sterna 3-6 each with small black spot on each side near middle; median carina on sterna 3-6 well developed; postero-lateral angles of sterna 3-5 with small spines, sternum 6 with long posterolaterally directed spine on each side; sternum 7 parallel-sided, postero-lateral angles strongly produced posteriad; posterior margin of sternum 8 slightly incised medially (
Fig. 4
).
Pygophore (
Figs. 6-7
) brownish, dorso-ventrally flattened, postero-lateral angles each with tuft of long setae; parameres apically pointed, ventrally with setigerous punctures.
Female (
paralectotype
) (
Fig. 41
). Length
8.2 mm
, width of pronotum between humeral angles approximately 4.1 mm (right spine missing); punctures on body reddish; metapleura only slightly swollen, less prominent in dorsal view; abdomen (
Fig. 5
) less narrowing posteriad, more flattened, unicolorous, without black round spots, median carina developed only on sterna 3-4; connexival spines as in
Fig. 5
.
Variability.
Male
paralectotype
differs from the
lectotype
in having the clypeus completely enclosed by mandibular plates; body length
7.4 mm
, length of antennomere 2 equal to
2.4 mm
.
Differential diagnosis.
Mahea sexualis
differs from
M. andriai
,
M. distanti
sp. nov.
, and
M. parvula
by having each humeral angle abruptly produced into a long spine, not conical. From
M. durrelli
sp. nov.
it differs by having the lateral pronotal margins regularly sinuated, the humeral spines not raised (
Figs. 2-3
), the metapleura distinctly swollen, differently shaped connexival spines (
Figs. 4-5
), and apex of each paramere pointed (
Figs. 6-7
) (see also the key).
Bionomy.
Unknown.
Distribution.
Island of Mahé (
Seychelles
). Known only from the
type
series.
Comments.
DISTANT (1909)
described
M. sexualis
based on both sexes, but he did not mention the number or the location of
syntypes
. The type locality was given unambigously as ‘Locality. Mahé’, but on the next line
DISTANT (1909)
wrote: ‘Dr. Schouteden has kindly sent me a male specimen of this species from
Madagascar
.’ The description was accompanied by a figure of a female from
Mahé
and a male from
Madagascar
.
KUMAR (1974)
examined three specimens of
M. sexualis
deposited in the BMNH – one male and one female from
Mahé
, and one male from
Madagascar
. He wrote: ‘… the
Madagascar
male is a distinct species, quite different from
Mahé
specimens. … Distant’s description covers both species and his type label is affixed to the
Madagascar
specimen. In these circumstances, I have taken the
Madagascar
specimen to be the type and have placed a label on it indicating this is the
holotype
. The species represented by the specimens from
Mahé
is being described elswhere.’ The
Madagascar
specimen, however, did not originate from the type locality, and thus it cannot be a
syntype
of
M. sexualis
either by
DISTANT (1909)
or
KUMAR (1974)
. The
lectotype
designation by
KUMAR (1974)
is therefore unjustified and in valid.
I had the opportunity to study three specimens of
M. sexualis
– one male and one female from BMNH, and one male from CUMZ – with the same locality labels and determination labels written most probably by the same hand (see Type material). Therefore, I regard all these specimens to be
syntypes
of
M. sexualis
. The male from CUMZ was choosen as the
lectotype
because it is better preserved and has the pygophore, which is lost in the male from BMNH. The
Madagascar
specimen designated as a
lectotype
by
Kumar (1970)
is currently described as
M. distanti
sp. nov.