Research Article |
Corresponding author: Santhamma Salini ( shalini.nbaii@gmail.com ) Academic editor: Pavel Stoev
© 2023 Santhamma Salini, R. G. Gracy, Romila Akoijam, Mehaboob K. Rabbani, K. Jacob David, Marcos Roca-Cusachs.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Salini S, Gracy RG, Akoijam R, Rabbani MK, David KJ, Roca-Cusachs M (2023) Revision of Acesines Stål and Dunnius Distant, resurrection of Mycterizon Breddin (Hemiptera, Heteroptera, Pentatomidae, Pentatominae), and description of a new species from India. ZooKeys 1148: 79-117. https://doi.org/10.3897/zookeys.1148.95629
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The genera Acesines Stål, 1876 and Dunnius Distant, 1902 (Hemiptera: Heteroptera: Pentatomidae: Pentatominae) were revised and redescribed with the description of Dunnius barpetensis Salini & Rabbani, sp. nov., based on specimens from Assam and Meghalaya, northeastern states of India. The genus Mycterizon Breddin, 1909 is reinstated from Dunnius, removed from the tribe Menidini, and redescribed. Consequently, the following new combinations are proposed: A. sordida (Kirby, 1891), comb. nov., Dunnius laticeps (Zheng & Liu, 1987), comb. nov., D. tridentatus (Xiong & Liu, 1995), comb. nov., and D. trifasciatus (Xiong & Liu, 1995), comb. nov. A lectotype is designated for Araducta bella (Distant, 1900a). Acesines bambusana Distant, 1918, and Mycterizon bellus stat. rev. are redescribed based on both male and female genitalia and Dunnius fulvescens (Dallas, 1851) is redescribed based on female genitalia.
Araducta bella, Axiagastini, lectotype, male genitalia, north-east India
The genus Acesines was first proposed by
Two specimens resembling Acesines were collected as part of the insect collection surveys, which were undertaken to the northeastern region of India, led the authors to investigate the taxonomic position of various species currently accommodated in genera Acesines and Dunnius. Hence this paper aims at revising these two genera, resurrecting the genus Mycterizon for D. bellus, describing a new species of Dunnius, redescribing D. fulvescens (the type species of Dunnius) based on female genitalia, and redescribing A. bambusana based on male and female genitalia. Dunnius sordida is transferred from Dunnius to Acesines and A. laticeps, A. tridentatus, and A. trifasciatus are transferred from Acesines to Dunnius. Additionally, taxonomic notes on Acesines sordida (Kirby, 1891), comb. nov. Dunnius laticeps (Zheng & Liu, 1987), comb. nov., Dunnius tridentatus (Xiong & Liu, 1995), comb. nov., Dunnius trifasciatus (Xiong & Liu, 1995), comb. nov., and A. breviceps are provided. As the types of the aforementioned species were not available for study, detailed redescriptions are not included.
All the specimens examined for the present study are deposited in the National Insect Museum (NIM), Indian Council of Agricultural Research-National Bureau of Agricultural Insect Resources, Bangalore, Karnataka, India (ICAR-NBAIR). Observations, dissections, and illustrations of male and female genitalia and general morphology were made using the stereozoom microscope, Nikon SMZ 745 (model C-FIR). Dissection and inflation of male genitalia followed
The type images of A. breviceps were obtained from Gunvi Lindberg, Swedish Museum of Natural History (
Terminology of general morphology follows
Acesines Stål, 1876: 65 (key to genera), 94 (description of type species). Type species: Acesines breviceps Stål, 1876: 94–95, by monotypy.
Acesines:
Colouration. Body pale brown with mosaic of ochraceous irregular patches; antennae pale; membrane pale brown, translucent; head and thorax (ventral side), ventral side of abdomen medially, pale yellowish; legs (except apical 1/2 of claws, black) and labium (except apical 1/2 of segment IV of labium, black) concolourous to abdomen.
Integument and vestiture. Body above covered with coarse, dark brown punctures; head (ventrally) and thoracic pleura with coarse, brown punctures; abdominal sternites with fine, brown punctures. Body glabrous, except antennae and legs moderately pilose. Male genitalia with ventral rim including the posterolateral lobes of the genital capsule, possessing short, golden setae. Female genitalia with valvifers VIII and IX, laterotergites VIII and IX and abdominal segment X provided with short setae.
Structure. Head (Fig.
Pronotum
(Fig.
Scutellum. Subtriangular, longer than broad at base; scutellar disc with basal 1/2 gibbous; posteriorly flat. Apex of scutellum narrowly rounded.
Hemelytra. Corium with anterodistal angles rounded, extending well beyond apex of scutellum. Membrane translucent with five or six simple veins, without reticulate venation.
Thoracic pleuron and sternum. Pro- and meso-sternum with median longitudinal carina abruptly narrowed anteriorly, not extending beyond procoxae; posteriorly in contact with nearly hexagonal metasternal carina; metasternal carina posteriorly hollowed out or grooved (Fig.
Legs. All femora unarmed, cylindrical, rounded in cross-section. All tibiae triangular in cross-section, their outer surface sulcate. All tarsi with segment II shortest, dorsally regularly rounded.
Pregenital abdomen. Connexivum slightly exposed. Posterolateral angles of abdominal ventrites angulate. Abdominal venter slightly convex medially, neither grooved nor keeled; ventrite III medially with prominent tubercle (Fig.
Male genitalia. Genital capsule (Figs
Female genitalia
(Figs
Acesines, based on morphological features, is closely related to Dunnius and has been treated as congeneric (
Neither the etymology nor the gender of the name Acesines were explicitly given in the original description. The name Acesines is probably borrowed from ancient Greek (meaning a tributary river of Indus), which is masculine according to the Article 30.1.4.2 of
Acesines bambusana Distant, 1918: 144 (original description). Holotype, India, Karnataka (NHM).
Acesines bambusana:
Acesines bambusana. India, Karnataka, south India, Chikkaballapura (= Chikkaballapur), T. V. Campbell Coll., 13.4355°N, 77.7315°E (Fig.
Acesines bambusana. Not examined, only image of type was seen. The original description seems to be based on more than one specimen as the length of the examined specimens is given as a range. The type is deposited in NHM, London, UK. The image of the syntype (Fig.
Many of the Indian types described by
India: Karnataka: 1♀, Shimoga, 06.x.2008, Umeshkumar; 1♂, NBAII (NIM); 1♀, Shimoga, 05.x.2008, Ex. light trap (sodium vapour lamp), Yeshwanth, H. M., NBAII (NIM); 1♀, 1♂, Shimoga, 06.x.2008, Ex. light trap (sodium vapour lamp), Umeshkumar, NBAII (NIM); 1♀, Kandali, Hassan [12°58.810'N, 76°02.513'E], 11.xi.2008, Yeshwanth, NBAII (NIM); 1♀, Forestry College Sirsi, 08.xii.2007, Ex. light trap (sodium vapour lamp), Umeshkumar, I. S., NBAII (NIM); 1♀, Hesaraghatta, 1.xii.2008, Umeshkumar (NIM); 1♂, 1♀, B.R. Hills, Chamarajanagar, 22.viii.2007, Ex. light trap (sodium vapour lamp), Yadava Babu R.K., NBAII (NIM); 1♂, Bengaluru, Attur, 19.ii.2018, Prabhu, G. (NIM); 1♀, B.R. Hills, Chamarajanagar, 22.viii.2007 Ex. light trap (sodium vapour lamp), Naveen Kumar, N., NBAII (NIM); 1♂, Shimoga, 06.x.2008, Ex. light trap (sodium vapour lamp), Yeshwanth, H.M., NBAII (NIM); 1♀, Bangalore, Hebbal, 04.ix.2013, Salini, S. (NIM); Tamil Nadu: 1♀, Annamalai Univ. Campus, 11°23'N, 79°43'E, 4.ii.2010, Umeshkumar, NBAII (NIM).
Colouration
(Figs
Acesines bambusana Distant 7 metasternal carina (arrow showing the hollowed out or grooved metasternal carina) 8 posterior apex of male abdomen 9 posterior apex of female abdomen 10 genital capsule (dorsal) 11 genital capsule (ventral) 12 genital capsule (caudal). Scale bars: 0.5 mm (7–9); 0.1 mm (10–12). Abbreviations: ap–angular process; st–short sclerotised tooth.
Acesines bambusana Distant 20 phallus (lateral) 21 terminalia (dorsal) 22 terminalia (ventral) 23 spermatheca 24 syntype label Mick Webb, NHM, London, UK 25 syntype (dorsal habitus), courtesy P. Kment. Abbreviations: ar–apical receptacle; pa–processes of aedeagus; vf VIII–valvifers VIII; vf IX–valvifers IX; lt VIII–laterotergite VIII; lt IX–laterotergite IX. Scale bars: 0.1 mm (20–23).
Integument and vestiture. Body above covered with coarse, dark brown punctures; head (ventrally) and thoracic pleura with coarse, brown punctures; abdominal sternites (lateral region surrounding the subrounded fields enclosing the spiracle) with fine, brown punctures. Body glabrous except antennae and legs moderately pilose. Male genitalia with ventral rim including the posterolateral lobes of the genital capsule, possessing short, golden setae. Female genitalia with valvifers VIII and IX, laterotergites VIII and IX, and abdominal segment X provided with short setae.
Structure. See the generic redescription.
Male genitalia. Genital capsule (Figs
Female genitalia. (Figs
(mm). Males (n = 5) as median (minimum–maximum). Body length 12.15 (10.13–15.85); head: length 1.71 (1.57–1.97), width (including eyes) 2.99 (2.61–3.51), interocular width 1.65 (1.51–1.88); lengths of antennomeres: I –0.55 (0.48–0.64), II – 1.16 (0.96–1.41), III – 1.40 (1.21–1.77), IV – 1.64 (1.43–1.97), V – 1.38 (1.19–1.54); lengths of labiomeres: I– 0.80 (0.61–1.03), II– 1.35 (1.10–1.66), III– 1.07 (1.00–1.18), IV– 0.64 (0.55–0.77); pronotum: length 2.99 (2.45–3.88), width (including humeri) 6.99 (6.12–8.31); scutellum: length 4.87 (4.13–5.99), width (at basal angles) 4.60 (4.00–5.55).
Females (n = 5) as median (minimum–maximum). Body length 11.54 (11.08–11.94); head: length 1.63 (1.56–1.66), width (including eyes) 2.98 (2.89–3.03), interocular width 1.65 (1.60–1.75); lengths of antennomeres: I –0.45 (0.42–0.47), II – 1.07 (1.01–1.13), III – 1.30 (1.27–1.32), IV – 1.53 (1.41–1.60), V –1.21 (1.18–1.24); length of labiomeres: I –0.67 (0.63–0.71), II –1.25 (1.13–1.33), III – 1.02 (0.98–1.13), IV – 0.62 (0.59–0.65); pronotum: length 3.12 (2.83–3.33), width (including humeri) 6.92 (6.77–7.03); scutellum: length 4.89 (4.73–5.03), width (at basal angles) 4.55 (4.35–4.66).
This species can be differentiated by the peculiar C-shaped crown of paramere, expanded dorsal conjunctival processes with hooked distal apex and the external female genitalia characters such as the short but wide triangular projection at middle the caudal margin of laterotergites VIII and the sclerotised rod-like structure expanded to an elongate, oval structure at the proximal end, beyond spermathecal dilation.
Specimens of A. bambusana were collected mainly by light trap, a few were also collected from its host plant bamboo, Bambusa vulgaris Schrad. ex. J.C. Wendl (Distant, 1918). A cluster of eggs were collected on outer surface of young sprout of bamboo. The eggs were pearl-white in colour and were laid in groups of five or six (Fig.
This species is presently only known from India.
Acesines breviceps
Stål, 1876: 94–95 (original description). Holotype: ♀, India Orientalis, deposited at the Swedish Museum of Natural History (
Acesines breviceps:
This species is likely to be conspecific with A. bambusana because of the similarity in external colouration and structural morphology. The differences (punctures on scutellum, colouration of outer margin of abdominal venter, small spinous projection at the caudal margin of laterotergite VIII) observed upon comparison of images of the female holotype specimen of A. breviceps (the photographs were provided by courtesy of Gunvi Lindberg) with female specimens of A. bambusana, were found to be insignificant. However, the synonymy of these species cannot be confirmed without the examination of male genitalia structures of both species. Unfortunately, there are no male specimens available for study in the case of A. breviceps.
Raphigaster sordida
Araducta sordida:
Dunnius sordidus:
This species was recorded from Aiyur (Tamil Nadu) by
Acesines breviceps Stål 26 habitus (dorsal) 27 habitus (ventral) 28 label data of A. breviceps typus 29 close up of posterior end of ventral side of female abdomen (terminalia). Photographed by Gunvi Lindberg (2021 Naturhistoriska riksmuseet). Original photograph cropped. Made available by the Swedish Museum of Natural History under Creative Commons Attribution 4.0 International Public License, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/legalcode).
Dunnius Distant, 1902: 225 (key to genera), 231–232 (original description). Type species: Raphigastor fulvescens Dallas, 1851: 283, by original designation.
Dunnius:
non Mycterizon Breddin, 1909: 279 (original description). Type species: Araducta bella Distant, 1900a: 427, by monotypy. Synonymised by
Colouration. Body ochraceous, sometimes with two yellow spots dorsally especially on pronotum; membrane pale brown, translucent; legs and antennae pale; abdominal spiracles outlined in black, sometimes with anterior and posterolateral angles of abdominal sternites III–VII black.
Integument and vestiture. Body on dorsal side with brown to black coarse punctures confluent to form narrow black streaks. Ventral side with punctures less dense on thoracic sternites and finer on abdominal sternites; legs with sparse, fine, black punctures.
Body glabrous, antennomeres I–IV with short, semi-erect, golden setae. Labium with sparse, fine, short setae, femora with fine, golden setae, tibiae, and tarsi with moderately dense, short, pale brown semi erect setae. Ventral side of genital capsule with brown, sparse, fine punctures; terminalia with valvifers VIII, laterotergite VIII and laterotergite IX with fine brown punctures. Genital capsule (median region of ventral rim, posterolateral lobes) with short golden setae. Female genitalia (median region of valvifers VIII, valvifers IX laterally, laterotergite VIII and IX caudally) with short, brown, semi-erect setae.
Structure. Body moderate size (8–13 mm long), widely oval, widest across second abdominal segment.
Head above flat, much shorter than width across compound eyes, lateral margins narrowly reflexed, slightly concave in front of compound eyes. Mandibular plates much wider, but as long as clypeus, not meeting in front of clypeus. Antennae with five antennomeres, slender; antennomere I cylindrical, shortest, stoutest, remaining antennomeres cylindrical and slender. Labium reaching or surpassing mesocoxae.
Pronotum. Anterior margin not collar-like, rather thin, median concavity to accommodate posterior margin of head, shallow; anterolateral angles with minute laterally directed teeth. Anterolateral margin obliquely straight, narrowly reflexed; posterior margin nearly straight, posterolateral angles rounded; humeri rounded. Disc of pronotum strongly convex with anterior 2/3 sloping downwards.
Scutellum. Triangular, longer than broad at base; scutellar disc with basal 1/2 gibbous; posteriorly flat. Apex of scutellum narrowly rounded.
Hemelytra. Corium with anterodistal angles rounded, extending well beyond apex of scutellum. Membrane translucent with five or six simple veins, without reticulate venation.
Thoracic pleuron and sternum. Pro- and meso-sternum with median longitudinal carina uniformly narrow, not extending beyond procoxae; metasternal carina developed into a cruciform structure with posterior apex not hollowed out or grooved and not in contact with the basal abdominal tubercle. External scent efferent system (Fig.
Legs. All femora unarmed, cylindrical, rounded in cross-section. All tibiae triangular in cross-section, their outer surfaces sulcate.
Pregenital abdomen. Connexivum slightly exposed. Posterolateral angles of abdominal ventrites angulate. Abdominal venter slightly convex medially, neither grooved nor keeled; ventrite III medially with a prominent tubercle (Fig.
Male genitalia. Genital capsule nearly quadrangular with posterolateral lobes (= caudal lobes) well developed, pointed and angular. Dorsal rim sublaterally with convex lobe-like outgrowth nearly concealing the 1+1 triangular tooth-like structure on infoldings of dorsal rim. Ventral rim medially with shallow, roughly rectangular notch. Paramere with crown C-shaped in lateral view, short neck and small plate-like apodeme. Phallus. Phallotheca broader than long, dorsal region bulbous and ventral margin nearly straight (in lateral view); dorsal conjunctival processes large and membranous subdivided into two processes. Processes of aedeagus fused to form a hollow structure, opening ventrally with broad, oval aperture enclosing short aedeagus; aedeagus tube-like with apex curved.
Female genitalia. Valvifers VIII transverse, broad and roughly quadrangular; valvifers IX single, roughly quadrangular sclerite; laterotergites IX oblique, elongate; short, denticle at caudal apex of laterotergites VIII and laterotergites IX. Spermathecal dilation long, regularly, obliquely fluted (Fig.
Based on the materials examined under Dunnius and Acesines, it is found that the species of Dunnius closely resembles those of Acesines, but the former possesses the cruciform metasternal carina, the posterior end of which is not notched or grooved, which differentiate it from species of Acesines. Based on the similarity of male genitalia characters (shape of paramere and shape of caudal lobes of genital capsule), A. laticeps, A. tridentatus, and A. trifasciatus are transferred here from Acesines to Dunnius (see the differential diagnosis and remarks under Acesines). However, the cruciform metasternal carina and the presence or absence of groove or notch at the posterior apex of metasternal carina, could not be verified as neither the original description of those species mentioned it nor were the types examined here. However, the new species of Dunnius dealt in this paper (see description D. barpetensis sp. nov.) closely resembles A. laticeps, A. tridentatus, and A. trifasciatus in external morphology and male genitalia (characteristic shape of paramere, phallus and caudal lobes of genital capsule) and possesses the cruciform process without the posterior notch or groove reveals that these species are congeneric. This taxonomic decision is also in conformity with studies by
Neither the etymology nor the gender of the name Dunnius were explicitly given in the original description. The name Dunnius is a Latin word, which is masculine according to the Article 30.1 of
India, Assam, Barpeta, Sorbhog, Ramie Research Centre, 26°31'25.3"N, 90°53'09.7"E.
Holotype : ♂ (NIM), ‘INDIA: Assam/ Barpeta, Sorbhog/ Ramie Research Centre/26°31'25.3"N, 90°53'09.7"E/ 09.iii.2021, Rabbani, M. K.// HOLOTYPUS/ DUNNIUS BARPETENSIS sp. nov./det. Salini. S., 2022 [p, red label]’. Holotype is pinned, the dissected male genitalia placed in a plastic microvial with glycerol attached to the same pin, the detached right forewing glued on card. Paratype (1♀): India: Meghalaya/ Anggalanggri, South Garo hills/ 25°20'53.0"N, 90°13'37.8"E/ 20.iii.2021, Rabbani, M. K.(NIM), dissected female genitalia placed in a glass microvial with glycerol attached to the same pin; abdominal tergites and ventrites glued on card; segment V of right antenna, whole tarsi including apical claws of right foreleg and left hind leg lost. The paratype bears the following identification label: ‘PARATYPUS / DUNNIUS BARPETENSIS sp. nov. / det. Salini. S., 2022 [p, yellow label]’.
Colouration. Body above pale brown to ochraceous; head including antennae, 1/2 of anterolateral margins of pronotum and dorsum of scutellum pale white. Ocelli reddish. 1+1 small, round pale white spots located on posterior margin of pronotal calli. Membrane pale brown, translucent. Ventral side including legs creamy white except the following: apex of labiomere IV, apical 1/2 of tarsal claws, spiracular outline, minute spot at the antero- and postero-lateral angles of abdominal sternites III–VII, black.
Integument and vestiture. Body above covered with coarse, black punctures, densely concentrated towards anterior margin of pronotum and lateral margins of scutellum. Ventral side of body with black punctures mostly coarse and dense on thoracic sternites. Legs with minute black punctures sparsely distributed. The punctures finer on abdominal sternites, appear as four faint, indistinct streaks, gradually disappearing towards posterior 1/2. Ventral side of genital capsule with brown, sparse, fine punctures; terminalia with valvifers VIII, laterotergite VIII and laterotergite IX with fine, brown punctures.
Body glabrous, except the following: antennae and femora with fine, semi-erect, short setae; labium with sparse, golden setae; tibiae with dense, brown, short, semi erect setae on ventral side and dorsally with moderately elongate brown setae, dense mat of setae at the posterior end of tibiae; tarsomeres on dorsal side with moderately elongate golden setae and dense mat of short, golden setae on ventral side of all tarsomeres. Genital capsule (median region of ventral rim, posterolateral lobes and the infoldings of ventral rim with cushion-like region on either side of the median notch) with short, golden setae. Female genitalia (median region of valvifers VIII, valvifers IX laterally, laterotergite VIII and IX caudally) with short, brown semi-erect setae.
Dunnius barpetensis Salini & Rabbani, sp. nov. 36 habitus (dorsal) 37 habitus (ventral) 38 external scent efferent system (arrow showing the peritreme) 39 close up of posterior end of ventral side of female abdomen (terminalia) 40 articulatory apparatus 41 genital capsule (dorsal) (arrow shows the triangular tooth-like structure). Scale bars: 1 mm (36, 37); 0.1 mm (38–41).
Structure. Head above flat, sloping downwards, much shorter than wide, lateral margins narrowly reflexed, slightly concave in front of compound eyes. Mandibular plates more than twice as wide as clypeus, but nearly as long as clypeus, not meeting in front of clypeus. Clypeus narrow throughout its length. Compound eyes moderately large, rounded, protruding out of the head outline in most of their width. Ocelli small, situated posteriorly near to posterior margin of head. Antenniferous tubercles short. Antennae with five antennomeres, slender, antennomeres from shortest to longest: I<IIb<IIa<IV<III; antennomere I approximately reaching apex of head, shortest and stoutest, antennomere IIa to cylindrical and slender and antennomere IV slightly thickened towards apex. Bucculae short, low, anterior apex angulate and sometimes developed into minute tooth. Labium passing mesocoxae, labiomere I as long as bucculae.
Pronotum. Anterior margin thin, with median concavity to accommodate posterior margin of head, shallow; anterolateral angles with tooth minute or indistinct laterally directed. Anterolateral margin obliquely straight, narrowly reflexed; posterolateral margin narrowly concave; posterior margin nearly straight, posterolateral angles rounded; humeri rounded. Disc of pronotum convex with anterior 2/3 sloping downwards.
Dunnius barpetensis Salini & Rabbani, sp. nov. 42 genital capsule (ventral) 43 genital capsule (caudal) 44, 45 parameres (different planes) 46 phallus (ventral) 47 phallus (dorsal) 48 phallus lateral. Scale bar: 0.1 mm. Abbreviations: ct–cushion-like triangulate region; pa–processes of aedeagus; dcp–dorsal conjunctival processes; lcp–lateral conjunctival processes; mcp–median conjunctival processes.
Scutellum. Subtriangular, longer than broad at base; basal 1/2 of scutellar disc, gibbous; posterior 1/2, flat; abruptly narrowed at 1/3 from apex; caudal apex of scutellum narrowly rounded.
Hemelytra. Corium with anterodistal angles angulate, extending well beyond apex of scutellum. Membrane translucent with six or seven simple veins, without reticulate venation.
Thoracic pleuron and sternum. Pro- and meso-sternum with median longitudinal carina narrow throughout the length except slightly high at anterior apex, not extending beyond procoxae; posteriorly in contact with cruciform metasternal carina (Fig.
Legs. Outer surface of tibiae sulcate. All tarsi with tarsomere II shortest, dorsally regularly rounded, tarsomeres I and III subequal.
Pregenital abdomen. Connexivum scarcely exposed. Posterolateral angles of abdominal ventrites with tooth minute or indistinct. Abdominal venter slightly convex medially, neither grooved nor keeled; ventrite III (= second visible abdominal segment) medially with tubercle short, apically rounded and stout.
Male genitalia
(Figs
Female genitalia. (Figs
(mm). Males (n = 1); Body length 12.77; head: length 1.84, width (including eyes) 3.01, interocular width 1.63; lengths of antennomeres: I – 0.50, II – 1.25, III – 1.05, IV – 1.67, V – 1.42; lengths of labiomeres: I– 0.89, II– 1.39, III– 0.83, IV– 0.74; pronotum: length 2.98, width (including humeri) 6.74; scutellum: length 4.63, width (at basal angles) 4.45.
Females (n = 1); Body length 14.12; head: length 1.92, width (including eyes) 3.24, interocular width 1.88; lengths of antennomeres: I – 0.57, II – 1.35, III – 1.16, IV – 1.62, V – 1.43; length of labiomeres: I – 1.02, II – 1.44, III – 1.14, IV – 0.71; pronotum: length 3.45, width (including humeri) 7.15; scutellum: length 5.17, width (at basal angles) 4.63.
This species resembles D. laticeps, D. tridentatus, and D. trifasciatus in external morphology and colouration and therefore difficult to differentiate unless the male genitalia has been examined. The characteristic shape of genital capsule (dorsal rim, ventral rim, 1+1 denticle-like structure on infoldings of dorsal rim), shapes of paramere and phallus can differentiate this species from its congeners.
The specific epithet, barpetensis, is based on the name of the type locality; adjective.
The species was collected on bamboo, Bambusa vulgaris Schrad. & J.C. Wendl.
This species is at present known only from Assam and Meghalaya.
Rhaphigaster (Raphigaster) fulvescens Dallas, 1851: 283 (original description). Holotype: ♀ (NHM: ? lost, M Webb, pers. comm.).
Rhaphigaster fulvescens:
Plexippus fulvescens:
Dunnius fulvescens:
Country unknown (Dallas, 1851).
Not examined, only image of type was seen. The original description was based on female specimen (or specimens?). The type is supposedly deposited in NHM, London; however, it appears to be lost at present (M Webb, pers. comm.). The image of the type (Fig.
India: Arunachal Pradesh: 1♀, Pasighat, 2–11 May 2014, Veena Kumari, K., ICAR-NBAIR (NIM).
Colouration Body above pale brown to ochraceous. Ocelli reddish. 1+1 small, round, yellow spots on anterior 1/2 of pronotum, located on posterior margin of pronotal calli. Small, pale yellow irregular markings scattered on the pronotal disc. Membrane translucent with brown veins. Antennae and legs paler than dorsal colouration. Ventral side concolourous to dorsal except the following: four narrow broken longitudinal stripes (two laterally and another two sublaterally, formed from coarse, black punctures), spiracular outline, posterolateral angles of abdominal sternites III–VII, moderately large and round spot on mesosternum, apex of labiomere IV, black.
Integument and vestiture. Body above (Fig.
Body glabrous except antennae and legs moderately pilose. Terminalia of female genitalia with valvifers VIII and IX, laterotergites VIII and IX provided with sparse, coarse, brown punctures.
Structure. See the generic redescription.
Male genitalia. Unknown.
Female genitalia
(Figs
(mm). Females (n = 1); Body length 11.16; head: length 1.57, width (including eyes) 2.72, interocular width 1.53; lengths of antennal segments: I –0.43, II – 1.25, III – 1.03, IV – 1.46, V– 1.31; length of labial segments: I –0.60, II – 1.25, III – 0.87, IV – 0.64; pronotum: length 2.66, width (including humeri) 6.47; scutellum: length 4.77, width (at basal angles) 4.04.
This species resembles other members of this genus externally but the genitalia characters like the laterotergites IX having the caudal margin irregularly truncated, smooth, without any denticle and the drop-shaped apical receptacle differentiates this species from its congeners.
India: Sikkim (Mungphu), Tamil Nadu (Udhagamandalam = Ootacamund) (Distant, 1900b), Arunachal Pradesh (Pasighat) (new record); Burma (Distant, 1902); China (Rider, unpublished catalogue).
Dunnius fulvescens (Dallas) 56 metasternal carina with cruciform posterior apex (arrow showing the cruciform posterior apex) and basal abdominal tubercle 57 external scent efferent system (arrow showing the peritreme) 58 close up of posterior end of ventral side of female abdomen (terminalia) 59 terminalia (dorsal) 60 terminalia (ventral) 61 spermatheca 62 spermathecal pump. Scale bar: 0.25 mm. Abbreviation: rs–ring sclerites.
Acesines laticeps Zheng & Liu, 1987: 187–188, 191, figs 25–29 (original description). Holotype: ♂, Yunnan (Mengla), China (Nankai University), 17.IX.1979, Zou Huan-guang leg.
Acesines laticeps:
Not examined. The description was based on a single male specimen (holotype) from Yunnan, China and is deposited in Nankai University as per the original description.
This species was originally described in the genus Acesines Stål, but the illustration of dorsal habitus and the male genitalia which were provided in the original description by
Acesines tridentatus Xiong & Liu, 1995: 264–266, fig. 2a–d (original description). Holotype: ♂, Yunnan (Tengchong), China (Kunming Institute of Zoology, the Chinese Academy of Science). Paratype: ♀, Yunnan (Tengchong), 27.IX.1981, Wang Jixian leg.
Acesines tridentatus:
Not examined. The description was based on one male and female each from Tengchong, China and is deposited in Kunming Institute of Zoology, the Chinese Academy of Science as per the original description.
See the note under D. laticeps comb. nov. This species was originally described in the genus Acesines Stål, but similar to members of Dunnius in external morphology and male genitalia like the shape of paramere, genital capsule (shape of caudolateral lobes, ventral and dorsal rim) and shape of phallus similar to that of D. barpetensis sp. nov. The absence of metasternal notch and the short basal abdominal tubercle, which is not in contact with metasternum (see under the note of D. laticeps), which is evident from the description and ventral habitus image of this species by
Acesines trifasciatus Xiong & Liu, 1995: 263–264, fig. 1a–d (original description). Holotype: ♂, Yunnan (Mengzhe), China, 19.VI.1984, Xiong Jiang leg. (Kunming Institute of Zoology, Chinese Academy of Science).
Acesines trifaciatus Xiong & Liu, 1995: 266 (lapsus calami).
Acesines trifaciatus:
Not examined. The description was based on a single male specimen (holotype) Yunnan (Mengzhe), China and is deposited in Kunming Institute of Zoology, the Chinese Academy of Science as per the original description.
See the note under D. laticeps comb. nov. This species was originally described in Acesines Stål, but is similar to members of Dunnius in external morphology and male genitalia in the shapes of paramere, genital capsule (shape of caudolateral lobes, ventral and dorsal rims), and shape of phallus, which are similar to that of D. barpetensis sp. nov. The absence of metasternal notch and the short basal abdominal tubercle, which is not in contact with metasternum (see under the note of D. laticeps), is evident from the description and ventral habitus image of this species by
Mycterizon
Breddin, 1909: 279 (original description). Type species: Araducta bella Distant, 1900a: 427, by monotypy. Synonymized with Dunnius by
Colouration. Body ochraceous, with irregular black markings on pronotum, scutellum and hemelytra; membrane smoky brown, translucent; legs and antennae pale white; apex of labium, small, transverse line below the spiracles on either side of abdomen, small, irregular spots laterad to spiracle on either side of abdomen, anterior and posterior lateral angles of abdominal sternites III–VII, black.
Integument and vestiture. Body on dorsal side with black, coarse punctures confluent to form narrow black transverse streaks especially on pronotum, sometimes forming medium to large, irregular spots; fine punctures on connexivum. Ventral side with punctures more concentrated laterad; punctures fine and less dense medially; femora with dense, coarse punctures and tibiae with fine, black punctures. Genital capsule (ventrally) including posterolateral lobes with fine pale brown punctures; valvifers VIII and laterotergite VIII with sparse, coarse, brown punctures.
Dorsum glabrous, antennomeres I–IV and labium with short, semi-erect, dense golden setae; legs with moderately elongate golden setae; ventral side of abdomen with dense short, golden pubescence. Genital capsule (dorsal rim, posterolateral lobes and the caudal 1/2 of genital capsule on ventral side) with moderately elongate, dense, semi erect, golden setae. Female genitalia (valvifers VIII, valvifers IX, laterotergite VIII and IX) with moderately long, golden semi-erect setae.
Structure. Head above flat, as broad as 1.5 times the head length, lateral margins not reflexed, distinctly concave in front of compound eyes, outline of anterior part of head disc inverted U-shaped, beyond the concavity on lateral margins, in front of compound eyes; dorsum of head disc with transverse impression medially along the imaginary transverse line connecting the anterior margins of compound eyes and another 1+1 short, C-shaped impression adjacent to inner margins of compound eyes. Head length behind compound eyes much shorter and accommodated in the shallow median concavity of anterior margins of pronotum. Mandibular plates nearly twice as wide as width of clypeus, moderately narrowed towards apex, nearly as long as clypeus, not meeting in front of clypeus. Compound eyes protruded and stylate-like. Antennae with five antennomeres, slender; antennomere I cylindrical, shortest and stoutest, nearly reaching apex of head, remaining antennomeres cylindrical and slender. Labium short, reaching mesocoxae.
Pronotum. Anterior margin collar-like, slightly concave medially, anterior pronotal margin including the minute, laterally directed denticle, nearly as wide as head width including compound eyes. Anterolateral margin obliquely straight, not reflexed, smooth; posterior margin concave medially, posterolateral margins obliquely straight, posterolateral angles rounded; humeri rounded. Disc of pronotum strongly convex with anterior 2/3 sloping downwards.
Scutellum. Longer than broad at base; scutellar disc slightly gibbous basally; lateral margins slightly convex in frenal portion; posterior 1/2 of scutellum, beyond frena, broad and nearly U-shaped, with apex broadly rounded.
Hemelytra. Corium with anterodistal angles rounded, extending beyond apex of scutellum. Membrane translucent with seven or eight simple veins, without reticulate venation.
Thoracic pleuron and sternum. Mesosternum with median longitudinal carina uniformly narrow, not extending beyond procoxae; metasternal carina low, less developed. External scent efferent system with peritreme well developed, short, nearly reaching mid-metapleuron, spout-like, obliquely elevated to pleural surface (Fig.
Legs. All femora unarmed, cylindrical and rounded in cross-section. All tibiae with median longitudinal sulcation, rounded beneath. tarsi dorsally regularly rounded, tarsomere II shortest and tarsomere I and III subequal.
Pregenital abdomen. Body moderate size (8–10.45 mm long), oblong, abdomen nearly as wide as width across pronotal humeri and possesses more or less uniform width throughout. Connexivum usually not exposed. Sternites smooth, devoid of furrows or ridges; basal abdominal sternites lacking tubercle or spine or distinct groove; posterolateral angles of sternites III–VII either angulate or sometimes with short, stout, an blunt tooth.
Male genitalia. Genital capsule nearly quadrangular with posterolateral lobes well developed and broadly rounded. Dorsal rim widely and deeply excavated concave with nearly straight middle margin. Ventral rim medially shallowly excavated and broadly concave. Paramere. Sclerotised, crown broad, subquadrate. Phallotheca longer than broad, with thecal process slightly developed; four pairs of conjunctival processes; processes of aedeagus fused mid longitudinally, partially enclosing aedeagus.
Female genitalia. Valvifers VIII transverse, broad and roughly quadrangular, with medial margins nearly straight; valvifers IX single, transverse, broad sclerite; laterotergites IX oblique, elongate; laterotergite VIII subtriangular with smooth caudal margin; spermatheca with proximal end of sclerotised rod, at the middle of lumen of spermathecal dilation, curved upwards; apical receptacle orbicular with three elongate ductules.
Araducta bella Distant, 1900a: 427 (original description). Syntype: ♂, Punduloya, Ceylon, Atkinson Coll. 92–6, 116 (NHM), London, UK, lectotype (present designation); Syntype: ♀, Punduloya, Ceylon, Atkinson Coll. 92–6, 116 (NHM), London, UK, paralectotype (present designation).
Dunnius bellus
Distant, 1902: 233, fig. 146 (redescription, figures of habitat in dorsal view, and mesothorax, metathorax and abdomen in ventral view; distribution);
Mycterizon bellus
Araducta bella. Ceylon (= Sri Lanka), Punduloya. Dunnius bellus. Ceylon (= Sri Lanka), Punduloya.
Mycterizon bellus (Distant), stat. rev. 63 habitus (dorsal) 64 habitus (ventral) 65 external scent efferent system (arrow showing the peritreme) 66 close up of posterior end of ventral side of male abdomen 67 close up of posterior end of ventral side of female abdomen (terminalia) 68 genital capsule (dorsal). Scale bars: 1 mm (63, 64); 0.5 mm (65); 0.1 mm (66–68).
Mycterizon bellus (Distant), stat. rev. 69 genital capsule (ventral) 70 genital capsule (caudal) 71, 72 paramere 73 articulatory apparatus 74 phallus (dorsal) 75 phallus (ventral). Scale bar: 0.1 mm. Abbreviations: ad – aedeagus; cp – capitate processes; ls – lobe-like ingrowths; pa – processes of aedeagus; dcp I – dorsal conjunctival processes (inner one); dcp II – dorsal conjunctival processes (outer one); lcp – lateral conjunctival processes; vcp – ventral conjunctival processes.
Not examined, only type image was seen. The original description of A. bella is based on a male specimen whereas that of D. bellus was based on a female specimen. The syntype male specimen of Araducta bella Distant, 1900a: 427 (Ceylon: Punduloya, Atkinson Coll., 92–6, NHMUK 013588914) herein designated as lectotype (Figs
India: Andhra Pradesh: 1♀, Tirupathi, 22.x.2008, Yeshwanth, H. M. ex light trap (sodium vapour lamp) (NIM); 3♀, 3♂ ARS, Nellore, 14°25.790'N, 079°59.922'E, 03.iv.2009, Yeshwanth, ex light trap (sodium vapour lamp) (NIM); 2♂, ARS, Anakapalli, 17°41.855'N, 083°00.253'E, 5.iv.2009, Yeshwanth (NIM); Goa: 1♀, MRC. coll. Karnataka: 3♀, 1♂, Brahmavara, Udupi, 28.ix.2007, Naveen Kumar, ex light trap (sodium vapour lamp) (NIM); 2♀, Arabhavi, Belgaum, 12.ii.2008, Naveen Kumar, ex light trap (sodium vapour lamp) (NIM); 2♂, same data as former except 13.ii.2008, Yadava Babu; 1♀, Bandipur, Hangla, 19.xi.2008, 11°42.075'N, 076°37.685'E, Yeshwanth (NIM); 1♀, Markanja, D. Kannada, 12.xi.2009, Umeshkumar, ex light trap (sodium vapour lamp) (NIM); 1♀, Hessaraghata, 1.xii.2008, Umeshkumar (NIM); 7♂, 2♀, Brahmavara, Udupi, 13°25'N, 74°45'E, 79 m, 29.v.2014, Naveen, ex light trap (NIM); 1♀, CPCRI, Vittal, 06.iv.2018, David, K. J. (NIM); Kerala: 2♀, Kozhikode, 24.i.2008, 11°16.678'N, 075°50.647'E, Naveen Kumar, ex light trap (sodium vapour lamp) (NIM); 1♂, 1♀, ZSI, Calicut, 11°25'N, 75°77'E, 18.xi.2012, Devaraj, R., ex light trap (sodium vapour lamp), NIM-2022 (NIM); 1♂, CPCRI, Kasaragod, 12°31'N, 74°57'E, 6.xii.2012, Umeshkumar, S., ex light trap (sodium vapour lamp), NIM-2022 (NIM); 1♂, same data as before except date 4.xii.2012 (NIM); 2♂, 1♀, ZSI, Calicut, 24.iv.2014, V. Naveen, ex light trap (NIM); 1♀, no label (NIM); Tamil Nadu: 1♀, Yelagiri, Javadi Hills, 16.vi.2016, Ramesh Kumar, A.
Mycterizon bellus (Distant), stat. rev. 76 phallus (lateral) 77 terminalia (dorsal) 78 terminalia (ventral) 79 spermatheca. Scale bar: 0.1 mm. Abbreviations: ad – aedeagus; ar – apical receptacle; rs – ring sclerites; lt VIII – laterotergite VIII; lt IX – laterotergite IX; vf VIII – valvifers VIII; vf IX – valvifers IX.
Colouration
(Figs
Integument and vestiture. Body above covered with coarse, black punctures confluent to form irregular markings on dorsum especially on pronotum and scutellum. Ventral side of body with coarse and dense black punctures mostly concentrated towards lateral sides on thoracic sternites. Femora of legs with coarse, black, dense punctures and tibiae with fine black punctures. The punctures finer on abdominal sternites, concentrated towards laterally. Ventral side of genital capsule including posterolateral lobes with fine pale brown punctures; terminalia with valvifers VIII and laterotergite VIII with sparse, coarse, brown punctures.
Body glabrous, except the following: antennae with fine, golden pubescence; legs with setae moderately elongate and semi erect; tibiae with dense, brown, short, semi erect setae on ventral side and dorsally with moderately elongate brown setae, dense mat of setae at the posterior end of tibiae; tarsomeres on dorsal side with moderately elongate golden setae and dense mat of short, golden setae on ventral side of all tarsomeres; labium with sparse, golden setae. Genital capsule (middle margin of dorsal rim, posterolateral lobes and the caudal 1/2 of genital capsule on ventral side) with moderately elongate, dense, semi erect, golden setae. Female genitalia (valvifers VIII, valvifers IX, laterotergite VIII and IX) with moderately long, golden semi-erect setae.
Structure. See the generic redescription.
Male genitalia
(Figs
Female genitalia. (Figs
(mm). Males (n = 5) as median (minimum–maximum). Body length 8.63 (8.08–9.09); head: length 1.90 (1.82–1.98), width (including eyes) 2.91 (2.85–3.01), interocular width 1.74 (1.65–1.78); lengths of antennomeres: I – 0.56 (0.46–0.68), II – 0.68 (0.54–0.77), III – 1.25 (1.20–1.33), IV – 1.58 (1.47–1.68), V – 1.55 (1.50–1.63); lengths of labiomeres: I – 0.63 (0.51–0.73), II – 0.86 (0.79–0.93), III – 0.60 (0.56–0.63), IV – 0.52 (0.46–0.60); pronotum: length 2.12 (1.92–2.33), width (including humeri) 5.07 (4.82–5.32); scutellum: length 4.17 (3.84–4.31), width (at basal angles) 3.33 (3.28–3.48).
Females (n = 5) as median (minimum–maximum). Body length 10.26 (9.83–10.73); head: length 2.05 (2.01–2.13), width (including eyes) 3.19 (3.12–3.37), interocular width 1.99 (1.97–2.04); lengths of antennomeres: I –0.59 (0.55–0.64), II – 0.68 (0.56–0.74), III – 1.35 (1.26–1.44), IV – 1.72 (1.71–1.76), V –1.74 (1.73–1.75); lengths of labiomeres: I –0.61 (0.54–0.66), II –0.97 (0.91–1.04), III – 0.61 (0.56–0.75), IV – 0.53 (0.51–0.60); pronotum: length 2.63 (2.40–2.78), width (including humeri) 5.95 (5.62–6.44); scutellum: length 4.94 (4.64–5.31), width (at basal angles) 3.90 (3.70–4.11).
Though the species bellus neither possess the basal abdominal tubercle nor the metasternal cruciform process,
India: Bihar, Odisha, Tamil Nadu (
The genus Dunnius originally included four species, viz., D. bellus, D. fulvescens, D. minor, and D. sordida (Kirby) (Rider, 2022). The aforementioned nomenclatural changes and new taxa descriptions (A. sordida (Kirby, 1891), comb. nov; M. bellus (Distant, 1902), stat. rev.; D. laticeps (Zheng & Liu, 1987), comb. nov.; D. tridentatus (Xiong & Liu, 1995), comb. nov.; D. trifasciatus (Xiong & Liu, 1995), comb. nov.; and Dunnius barpetensis Salini & Rabbani, sp. nov.) led to the addition of two more species to the genus Dunnius. The genus Mycterizon, monotypic with M. bellus, is designated as type species by monotypy and presently considered as a member of Menidini, although its tribal placement is dubious.
Based on the examination of Indian Menidini and perusal of literature revealed that the members of this tribe do not appear to share a common ancestor and can be broadly assembled into three groups based on the combination of characters like shape of the scutellum, presence/absence of abdominal spine/tubercle, development of metasternal carinae:
Group 1 – spatulate scutellum, elongate abdominal spine present, metasternal carina narrow throughout its length;
Group 2 – subtriangular scutellum, elongate abdominal spine present, metasternal carina narrow throughout its length;
Group 3 – subtriangular scutellum, abdominal tubercle present, apex of which is placed in metasternal carina (broadening posteriorly).
Mycterizon bellus does not fit into any of the above-mentioned groups, but rather possesses a unique combination of characters such as a spatulate scutellum, a narrow metasternal carina, and the absence of either an abdominal spine or a tubercle. It also possesses other characters such as the head flat above, as broad as 1.5 times the head length, the external scent efferent system with peritreme well developed, short, nearly reaching mid-metapleuron, spout-like, obliquely elevated to the pleural surface, the shape of the genital capsule including a dorsal rim (slightly concave medially) and ventral rim (broadly concave, without denticles on infoldings), the shape of parameres (broad crown-shaped with stout, straight, finger-like process), and the phallus with elongate conjunctival processes. Considering these remarkable differences, it cannot be considered as a member of Menidini. Therefore, it is removed from the tribe and its tribal status cannot be decided except through phylogenetic studies using both morphological and molecular characters of the taxa included in Menidini and other related tribes.
The first author is very grateful to David A. Rider (North Dakota State University Fargo, USA) for assistance with the literature especially his catalogue pertaining to Axiagastini and Dunnius. Mick D. Webb is gratefully acknowledged by SS, for his prompt responses on the clarification of various type specimens and also for sharing literature and type images of a few taxa dealt in this paper. SS is also thankful to Petr Kment (National Museum, Prague, Czech Republic) for sharing his type images and also for his kindness in translating the literature pertaining to Mycterizon (German to English). SS also sincerely thanks Gunvi Lindberg (Swedish Museum of Natural History, Stockholm, Sweden) for the prompt responses to emails and also for sending the high-resolution images of the type species of A. breviceps. G. Prabhu is acknowledged for collecting the egg mass of Acesines bambusana. We are thankful to Assam State Biodiversity Board and Meghalaya Biodiversity Board for giving us permission to survey the various sites in Assam and Meghalaya, respectively. We are grateful to S.N. Sushil (Director, ICAR-NBAIR, Bangalore, India) for the facilities extended for this work. The work was financially supported by the Science and Engineering Research Board (SERB), Department of Science and Technology, Government of India (CRG/2019/001619).
Part 1
Data type: Phylogeny figure (image file)
Part 2
Data type: Phylogeny figure (image file)