Content uploaded by Hemant Ghate
Author content
All content in this area was uploaded by Hemant Ghate on Oct 03, 2018
Content may be subject to copyright.
Accepted by D. Rédei: 15 Jun. 2018; published: 22 Aug. 2018
Licensed under a Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0
ZOOTAXA
ISSN 1175-5326 (print edition)
ISSN
1175-5334
(online edition)
Copyright © 2018 Magnolia Press
Zootaxa 4461 (3): 421
–
428
http://www.mapress.com/j/zt/
Article
421
https://doi.org/10.11646/zootaxa.4461.3.7
http://zoobank.org/urn:lsid:zoobank.org:pub:B4AA7661-2562-4659-ADF2-B17F38CC592F
First record of the genus Gomesius (Hemiptera: Heteroptera: Reduviidae:
Emesinae) from India, with description of a new species
H.V. GHATE
1,3
& MIRJOY MATHEW
2
1
PG Research Centre, Department of Zoology, Modern College of Arts, Science and Commerce, Pune 411 005, India.
2
Government College of Arts, Science & Commerce, Quepem, Goa. E-mail: mirjoymathew02@gmail.com
3
Corresponding author. E-mail: hemantghate@gmail.com
Abstract
Gomesius indicus sp. nov. (Hemiptera: Heteroptera: Reduviidae: Emesinae: Leistarchini), collected in Goa State, India,
is described. This is the first record of the genus Gomesius Distant, 1903, from India.
Key words: Heteroptera, Reduviidae, Emesinae, new species, Indomalaya
Introduction
A male specimen of an emesine assassin bug (Hemiptera: Heteroptera: Reduviidae) collected in Mollem, Goa,
India, was identified as belonging to the genus Gomesius Distant, 1903, based on the monograph of Wygodzinsky
(1966). This genus has not been recorded from India before (Wygodzinsky 1966, Maldonado Capriles 1990,
Ambrose 2006).
Kirkaldy (1901) described the genus Algol Kirkaldy, 1901, and its single included species Algol hesione
Kirkaldy, 1901, based on a male specimen collected in Sumatra. Bergroth (1906) showed that Algol was
preoccupied, and transferred A. hesione to its junior but valid synonym Gomesius. Five further species of Gomesius
have been reported: G. predatorius Distant, 1903 (the type species of Gomesius), described based on a nymph from
Ceylon (=Sri Lanka) (Wygodzinsky 1966) and never recorded subsequently, with the adult still unknown; G.
insaturabilis Bergroth, 1915, also described from Java (Bergroth 1915) and later considered as a junior synonym of
G. hesione by Wygodzinsky (1966); G. b e r g ro t h i Wygodzinsky, 1966 (type locality: Sumatra); G. l o b a t u s
Wygodzinsky, 1966 (type locality: New Guinea); and G. uniformis Wygodzinsky, 1966 (type locality: Sumatra).
Thus there are five species included in Gomesius at present and none of them has been recorded from India so far.
In fact, not much information has been published on the genus after Wygodzinsky (1966); these include brief
diagnoses and some illustrations of the widely distributed G. hesione with new records from the Ryukyu
Archipelago of Japan (Ishikawa & Takai 2003, Ishikawa & Yano 2006) and Taiwan (Rédei & Tsai 2010). The
taxonomic history and a list of synonyms of Gomesius was given by Wygodzinsky (1966). Maldonado-Capriles
(1990) listed the known species, type localities and synonyms. These details are not repeated here.
Gomesius is included in the tribe Leistarchini, and is recognized by a prominent penicillate process as the basal
element of the posterovental series of spiniform processes of fore femur, which is situated at some distance from its
base. In addition the diagnostic characters of the genus include the presence of a small but distinct lateral
spiniferous process or spine on external face of fore femur, placed just in front of the penicillate process; fore tarsus
being longer than fore tibia, non-segmented; posterior lobe of pronotum being small, not covering mesonotum; and
scutellum and metanotum lacking spines (Wygodzinsky 1966).
GHATE & MATHEW
422
·
Zootaxa 4461 (3) © 2018 Magnolia Press
Material and methods
A single male bug collected in Goa State, India, was studied under a Leica stereozoom (MZ6) microscope and
photographed with an attached Canon Powershot S50 camera. Several images were stacked using Combine ZM
software and the images were processed with Adobe Photoshop CS5. Measurements were done with Erma stage
and ocular micrometer and an accurate scale. The pygophore was dissected after treating the last three abdominal
segments with hot 10% KOH. The detached pygophore was soaked overnight in 5% KOH at room temperature, the
phallic complex was dissected, stained with dilute methylene blue before clearing in order to make some parts
more clearly visible. The parameres and the phallus were separated in distilled water and mounted in polyvinyl
lactophenol (PVLP) with lignin pink dye, and photographed. The specimen (without pygophore) was briefly
treated with dilute acetic acid, washed with 50 and 70% alcohol and then dry mounted.
Taxon o m y
Subfamily Emesinae
Tribe Leistarchini Stål, 1863
Genus Gomesius Distant, 1903
Algol Kirkaldy, 1901: 54 (junior homonym of Algol Sollas, 1888, Spongia; synonymized by Bergroth 1906: 321). Type species
by monotypy: Algol hesione Kirkaldy, 1901.
Gomesius Distant, 1903: 210, 212. Type species by original designation: Gomesius predatorius Distant, 1903.
Isachisme Kirkaldy, 1904: 280. Unnecessary new name for Algol Kirkaldy, 1901.
Gomesius: Hsiao & Ren (1981: 395) (redescription); Maldonado Capriles (1990: 101) (catalogue); Putshkov & Putshkov
(1996: 158) (catalogue, Palaearctic Region); Wygodzinsky (1966: 117) (redescription, synonyms and key to species);
Rédei & Tsai (2010: 16) (diagnosis).
Gomesius indicus sp. nov.
(Figs. 1–25)
Diagnosis. Gomesius indicus sp. nov. can be differentiated from other congeners by a combination of the following
characters: eyes large, reaching ventral outline of head in lateral view; mesonotum with a pair of shining dark
brown, round and slightly sunken areas near posterior border; presence of four pairs of tubercles - one pair on each
of abdominal sternites four to seven, lack of lobate extensions on connexival margins; laterally and ventrally fully
visible eighth abdominal sternite.
Description. Male. Measurements (in mm). Total length to the tip of abdomen 23. Head length 1.5; length of
anteocular portion 0.75; length of postocular portion 0.35; eye diameter measured horizontally in lateral view 0.60;
lengths of antennal segments: I: 10.00; II: 6.50; III: 3.25; IV: 4.25; labium: total length 1.82; lengths of labial
segments: II (first visible): 0.50; III: 0.50; IV: 0.82; total length of pronotum 3.12; mesonotum 2.50; legs (lengths):
fore coxa 4.00; femur 5.30; tibia 1.30; tarsus (including claw) 2.00; middle coxa 0.87; femur 15.0; tibia 17.0; tarsus
(including claw) 0.70; hind coxa 0.95; femur 20.5; tibia 25.0; tarsus (including claw) 0.81. Pygophore length 1.60;
length from base to parameres 1.50; maximum width at base of parameres 0.87.
Color and integument: Body surface partly dull partly subshining. Body dark brown with a few ochraceous
spots or blotches, without any conspicuous pattern; legs more ochraceous with dark brown spots (Fig. 8, 9, 11).
Head with a horizontal dark brown stripe across eye laterally (Fig. 2), dorsally with brown blotch centrally, on
either side of median pale line of setae, in between eyes (Fig. 4, 6). Antenna dark brown, with irregular ochraceous
marking (Fig. 3); second segment mostly ochraceous with a basal, apical and few middle dark annulations, third
and fourth segments almost entirely ochraceous, with faint basal and apical brownish spots.
Pronotum darker, with few irregular ochraceous blotches; mesonotum brown, base with a pair of round, dark
brown, slightly sunken and shining areas (Figs. 7). Scutellum and metanotum dark brown. Fore coxae and femora
with fine dark brown elongate spots on external as well as internal surfaces, those on coxae mostly hidden under
Zootaxa 4461 (3) © 2018 Magnolia Press
·
423
FIRST RECORD OF GOMESIUS FROM INDIA
setae; similar elongate dark spots on mid and hind femora in apical portion only (Fig. 1). Mid femora brown with
ochraceous markings while hind femora pale brown with indistinct markings; mid tibiae more ochraceous than
femora with a few dark brown blotches; hind tibia very pale brown except in apical region where colour is dark;
tarsus dark. Forewing pale brown with fuscous blotches or bands along major veins (Fig. 10).
Abdominal tergites brownish with indistinct, median, longitudinal ochraceous line on first four or five
segments; sixth to seventh tergites with two median parallel dark brown longitudinal lines. Underside of head,
thoracic and abdominal sternites brown; sternites VII, VIII and pygophore very dark brown; median, longitudinal
broad ochraceous band present on abdominal sternites VI–VIII and pygophore, this band very prominent on
seventh and eighth sternites as well as on pygophore (Figs. 11, 17). Spiracles surrounded by whitish annulus.
Vest i t u re: Entire body clothed with very fine, adpressed, colorless or golden setae. Head dorsally covered with
three lines of pale setae; antennal setae mostly fine, short, adpressed, along with few slightly longer erect setae,
Pronotum with dense cover of setae, with a median band with more dense setae. Mesonotum with thick,
longitudinal lines of setae giving appearance of median and a pair of lateral pale lines. Scutellum and metanotum
also with two rows of pale setae. Sternum and abdominal sternites with a cover of fine setae. All legs covered with
moderately dense fine setae. Hind tibia with scattered, small, dark spine-like setae.
FIGURES 1–7. Gomesius indicus sp. nov., male holotype. 1, anterior half of body, lateral view; 2, head, lateral view; 3,
antenna, first segment; 4, head, dorsal view; 5, pronotum, lateral view; 6, head and pronotum, dorsal view; 7, mesonotum,
scutellum and basal portion of forewings, dorsal view. Scale bars: 1 mm.
GHATE & MATHEW
424
·
Zootaxa 4461 (3) © 2018 Magnolia Press
Structure: Head elongate, more or less fusiform in lateral view, gently rounded dorsally, more or less flat
ventrally; anteocular about twice longer than postocular portion, the latter with sides converging posteriorly in
dorsal and lateral views. Interocular transverse sulcus or furrow distinct in dorsal view but less so in lateral view,
conspicuously backwardly curved but not attaining level of posterior border of eyes, with a pair of small tubercles
dorsomedially on posterior border of transverse sulcus (Figs. 2, 4, 6). Eyes large and reaching ventral margin of
head. Labium with second (first visible) and third (second visible) segments moderately stout, fourth (third visible)
slender and pointed at tip; overall labium straight, not bent between first and second visible segments. First two
visible segments of labium subequal in length, third longest; distal tip of first visible segment of labium is in
vertical line with antenniferous tubercles above, second visible segment reaches beyond level of anterior border of
eye while last segment reaches level of fore coxae. Antennae inserted dorsally at middle of anteocular portion (Fig.
2). Pronotum elongate, subcylindrical, with anterior and posterior one third broader than median narrowed part,
with very small but distinct hind lobe, its posterior border not covering mesonotum (Fig. 5, 6). Scutellum and
metanotum without spines. Posterior border of prosternum distinctly emarginated (Fig. 12, 13). Forelegs
moderately stout and long; fore coxae slender than fore femora; fore femora slightly constricted near middle and
widened again distally and then almost subparallel. Each fore femur with posteroventral and anteroventral series of
spiniform setae and one stout process on outer surface, slightly in front of penicillate process. Posteroventral series
beginning at a distance from base of femur equal to one-third of total length of the article, composed of one basal,
elongate, penicillate process followed by a large number of slender spiniform setae inserted on short, wartlike
bases (Figs. 8, 9). Anteroventral series beginning distinctly apicad of basal process of posteroventral series, not
interrupted but strongly curved at base, consisting exclusively of smaller, slender spiniform setae. Tibia short and
stout, about one-fourth length of femur; ventrally with one series of short, adpressed, spiniform setae. Tarsus not
segmented, longer than tibia and gently curved. One simple, very small claw only (Figs. 1, 8, 9). Mid and hind legs
long; hind femora very long, surpassing apex of abdomen. Claws long and slender. Forewings narrow, not attaining
apex of abdomen, leaving about 2.5 mm length of abdomen exposed, with venation as shown in Fig.10. Abdomen
elongate, parallel-sided, more or less widened posteriorly, connexivum moderately broad; posterior angles of
connexivum of sixth and seventh segment angularly produced backward (Fig. 11). Abdominal sternites IV–VII
with a pair of sublateral protuberances or tubercles near anterior border, those on fifth and sixth prominent than
others; distance between two tubercles of same segment about 0.8 mm while distance between tubercles of
consecutive segments about 2.0 mm (Fig. 15). Tergite VII rounded at posterior border; sternite VIII visible fully
from lateral and ventral side (Figs. 17, 18). Segment VIII and pygophore slightly compressed laterally.
Male genitalia. Pygophore elongate, somewhat pear shaped in lateral view (Fig. 18), almost rectangular in
dorsal (Figs. 16, 19) and ventral views (Figs. 17, 20); dorsal bridge very short; posterior border of pygophore with
broad, apically notably emarginated process, tips of this emargination well-rounded (Figs. 20, 21). Parameres
curved, densely setose and only moderately thickened in middle part (Fig. 25).Phallus symmetrical. Articulatory
apparatus stout. Phallosoma short, subcylindrical, its distal opening somewhat wide. Endosoma with numerous
small, dark sclerites dispersed all over (Figs. 22–24).
Female unknown at present.
Type material. Holotype: male, INDIA, Goa, Mollem, xi.2016, leg. Mirjoy; presently in the private
collection of H.V. Ghate, Modern College, and will be deposited in the Zoological Survey of India, Western
Regional Station, Pune.
Etymology. The specific name is the Latin adjective indicus, -a, -um (meaning ‘Indian’, ‘from India’),
referring to the fact that this is the first species of Gomesius documented from India.
Discussion
Gomesius indicus sp. nov. differs from G. lobatus in lacking the lobate extensions on connexival segments III–VII,
although G. indicus sp. nov. also has sternite VIII completely exposed as in G. lobatus. G. uniformis has uniformly
dark brown forelegs and forewings while in G. i nd i c u s sp. nov. the legs are brownish or partly dark brown, with a
pale ochraceous pattern, and in fore femur the pattern is different on inner and outer face. Like G. bergrothi, G.
indicus sp. nov. also shows presence of a pair of small sublateral protuberances / tubercles on some abdominal
sternites, but in G. b e r g ro t h i these are on sternites III–VI, while in G.indicus sp. nov. on sternites IV–VII.
Additionally, in G. bergrothi the posterior border of pygophore has the usual long and apically incised or
Zootaxa 4461 (3) © 2018 Magnolia Press
·
425
FIRST RECORD OF GOMESIUS FROM INDIA
emarginated process but the incision is very shallow while in G. i n d i c u s sp. nov. the process of the pygophore is
short but more deeply and widely incised, with prominent, evenly rounded tips. Also, in G. b erg r o th i sternite VIII is
visible only partly on lateral side while in G. indicus sp. nov. it is fully visible laterally and ventrally; parameres of
G. b e r g ro t h i are also relatively less curved and broader than in G. i n d i cu s sp. nov. Eyes are large in G. indicus sp.
nov. and reach ventral outline of head in lateral view, while in G. bergrothi the eyes are smaller and remote from
dorsal and ventral margin of the head in both sexes. Eyes are also small in G. uniformis and sternite VIII is also
completely hidden making it distinct from G. i n d i cu s sp. nov.; the incision on tip of the posterior process of
pygophore is relatively shallower in G. uniformis than in G. indicus sp. nov. Gomesius lobatus has eyes very similar
to that of the new species, but G. lobatus is unique in Gomesius in possessing lobate extensions on connexivum.
FIGURES 8–15. Gomesius indicus sp. nov., male holotype. 8, foreleg, lateral view (scale bar 1 mm); 9, fore femur (except
basal portion), tibia and tarsus; 10, forewing, dorsal view; 11–14, ventral views; 11, whole body, (scale bar 2 mm); 12, thoracic
sternum; 13, prosternum; 14, meso- and metasterna; 15, abdominal sternites, ventrolateral view (scale bar 1 mm), white
pointers showing sternal tubercles.
GHATE & MATHEW
426
·
Zootaxa 4461 (3) © 2018 Magnolia Press
FIGURES 16–25. Gomesius indicus sp. nov., male holotype, genitalia. 16–20, pygophore and parameres; 16, in situ, dorsal
view; 17, same, ventral view (scale bar 1 mm); 18, same, lateral view; 19, detached, dorsal view; 20, same, ventral view; 21,
apex of pygophore; 22, phallus, inverted, lateral view (scale bar 0.5 mm), 23, phallus, everted, lateral view; 24, endosoma; 25,
parameres (outer view on left, inner view on right).
Gomesius indicus sp. nov. cannot be compared with G. predatorius, because the latter species is of doubtful
identity, with the original description based on a nymph. There is some chance that the two species are conspecific,
but as currently there seems no chance to elucidate the identity of G. predatorius, we found it the best to describe
our specimen from Goa as new. This problem might be solved in the future only if the development of molecular
techniques will allow extraction of DNA from the type of G. predatorius.
Zootaxa 4461 (3) © 2018 Magnolia Press
·
427
FIRST RECORD OF GOMESIUS FROM INDIA
Gomesius indicus sp. nov. is very similar to G. hesione in many characters such as coloration of some areas
(e.g. fore femur, last three sternites) and the appearance of pygophore in dorsal view. The ratio of length of
pronotum to length of mesonotum is also within the range mentioned by Wygodzinsky (1966); sternite VIII is
completely exposed in G. hesione as well as in G. indicus sp. nov.; the length of the unarmed basal portion of the
fore femur is one third the length of the femur in G. hesione and also in G. indicus sp. nov. Phallus and parameres as
well as the tip of the posterior process of the pygophore of G. hesione are however slightly different from the
condition found in G. indicus sp. nov., as it is evident from the illustrations of Wygodzinsky (1966), but, the
endosoma was not everted and the details are not shown and so cannot be compared. The most important
distinguishing character of the present species from G. hesione is the presence of a pair of sublateral protuberances
or tubercles each on abdominal sternites four to seven which were not documented in G. hesione, neither in any
species of Gomesius except in G. bergrothi. Another feature not mentioned in any Gomesius so far is the presence
of a pair of round, shining, dark brown, slightly sunken, areas at the base on mesonotum; these areas are devoid of
setae and hence reveal the colour of the integument.
All species of Gomesius, a Southeast Asian genus, described so far are from island localities. The presence of a
species in western coastal region of India is interesting and a thorough survey of eastern parts of India may reveal
its presence in other localities as well.
A literature-based key to the species of Gomesius
1 Abdominal sternites without small sublateral tubercles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
- Abdominal sternites with small sublateral tubercles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Connexivum without lobate extensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
- Connexivum with lobate extensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G. lobatus Wygodzinsky, 1966
3 Eyes large, reaching ventral border of head in lateral view, sternite VIII of male exposed laterally as well as ventrally . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G. indicus sp. nov.
- Eyes small, remote from ventral and dorsal outlines of head in lateral view, sternite VIII of male exposed only laterally. . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G. bergrothi Wygodzinsky, 1966
4 Color of fore femur uniformly dark brown; sternite VIII of male not visible . . . . . . . . . . . . . .G. uniformis Wygodzinsky, 1966
- Color of fore femur not uniform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G. h e si on e (Kirkaldy, 1901)
(key excludes G. predatorius as it was described on the basis of a nymph)
Acknowledgements
We are indebted to Dávid Rédei (Nankai University, China) and Tadashi Ishikawa (Tokyo Agriculture University,
Japan) for constantly helping our work on this group of insects; it would be impossible to do this work without their
unfailing support. We are grateful to Hélcio Gil-Santana (Oswaldo Cruz Institute, Brazil) for critically reviewing
the manuscript and to Dávid Rédei for additional inputs. Swapnil Boyane prepared plates for this paper and helped
during photography and we thank him for that. We are grateful to the authorities of our respective colleges for
support and encouragement.
References
Ambrose, D.P. (2006) A checklist of Indian assassin bugs (Insects: Heteroptera: Reduviidae) with taxonomic status,
distribution and diagnostic morphological characteristics. Zoos’ Print Journal, 21 (9), 2388–2406. Available from: http://
www.zoosprint.org/ZooPrintJournal/2006/September/2406sup.pdf (Accessed 20 July. 2018)
Bergroth, E. (1906) Zur Kenntnis der Ploeariinen. Verhandlungender kaiserlich-königlichen zoologisch—botanischen
Gesellschaft in Wien, 56, 305–321.
https://doi.org/10.5962/bhl.part.1226
Bergroth, E. (1915) Some Javanese Hemiptera collected by E. Jacobson and Th. H. MacGillavry. Zoologische Mededeelingen,
21, 109–123.
Distant, W.L. (1903) The Fauna of British India, Rhynchota. Vol 2. Part I. Heteroptera.Taylor and Francis, London, 242 pp.
Hsiao, T.Y. & Ren, S.Z. (1981) Reduviidae. In: Hsiao, T.Y., Ren, S.Z., Zheng, L.Y., Jing, H.L., Zou, H.G. & Liu, S.L. (Eds.), A
GHATE & MATHEW
428
·
Zootaxa 4461 (3) © 2018 Magnolia Press
handbook for the determination of the Chinese Hemiptera-Heteroptera. Vol. II. Science Press, Beijing, pp. 390–538. [in
Chinese]
Ishikawa, T. & Takai, M. (2003) Discovery of an emesine bug Gomesius hesione (Heteroptera: Reduviidae) from Japan.
Rostria, 51, 43–44.
Ishikawa, T. & Yano, S. (2006) New localities of the reduviid bugs (Heteroptera) in Japan. Rostria, 52, 1–20.
Kirkaldy, G.W. (1901) Six new Reduviidae from Sumatra. Notes from the Leyden Museum, 23, 53–57.
Kirkaldy, G.W. (1904) Bibliographical and nomenclatorial notes on the Hemiptera. No. 3. Entomologist, 37, 279–283.
https://doi.org/10.5962/bhl.part.2885
Maldonado Capriles, J. (1990) Systematic Catalogue of the Reduviidae of the World (Insecta: Heteroptera). Caribbean Journal
of Science, Special Edition, 1–694.
Putshkov, P.V. & Putshkov, V.G. (1996) Family Reduviidae Latreille, 1807—assassin-bugs. In: Aukema, B. & Rieger, Chr.
(Eds.), Catalogue of the Heteroptera of the Palaearctic Region. Vo l . 2. Cimicomorpha I. Netherlands Entomological
Society, Amsterdam, pp. 148–265.
Rédei, D. & Tsai, J.F. (2010) A survey of the emesine assassin bugs of the tribes Collartidini, Leistarchini, Emesini, and
Metapterini of Taiwan (Hemiptera, Heteroptera, Reduviidae). Deutsche Entomologische Zeitschrift, 57 (1), 11–36
Wygodzinsky, P. (1966) A monograph of the Emesinae (Reduviidae, Hemiptera). Bulletin of the American Museum of Natural
History, 133, 1–614.
