Halys Fabricius, 1803

Salini, S., 2019, Revision of the genus Halys (Hemiptera: Pentatomidae) with description of a new species from India, Zootaxa 4586 (2), pp. 351-375 : 353-354

Halys Fabricius, 1803

Halys Fabricius, 1803: 180 . Type species by subsequent designation ( Kirkaldy, 1900: 263): Halys dentata Fabricius, 1803 (= Halys serrigera Westwood, 1837 ).

Differential diagnosis. Members of this genus are usually dull coloured, characteristic for their elongate head, with at least one pair of teeth on lateral margins of head, round apex of bucculae (lacking tooth), elongate labium resting in the median longitudinal groove on the ventral side of the abdomen, well exposed connexivum and spoutshaped (crescent-shaped) peritreme ( Fig. 91 ), which is usually not extending beyond middle of metapleuron. Male genitalia with genital capsule quadrangular, paramere roughly C-shaped with crown expanded, with or without ridges, provided with one or two teeth in various positions; inflated phallus with a pair of process of aedeagus, either free or fused; usually with two pairs of membranous conjunctival processes. Laterotergite IX of female terminalia is distinctly shorter than apex of abdomen.

Redescription. Head ( Figs 10–16 ) flattened dorsally, coplanar with pronotum in lateral view; lateral margin of mandibular plates with one or two pairs of teeth, first pair just in front of compound eyes, second pair (if present) at anterior third; anterior third of mandibular plates abruptly narrowing, extreme apex rounded, not meeting in front of clypeus; clypeus nearly of equal width throughout and open anteriorly, usually slightly longer than mandibular plates, sometimes of equal length. Antenniferous tubercles ( Fig. 11 ) small, visible from above along with base of antennae. Antennae five segmented, slender. Antennal segments of variable length, segment I cylindrical, shortest and stoutest, not reaching apex of head, remaining segments slender, nearly of uniform thickness. Bucculae ( Fig. 16 ) rounded anteriorly. Labrum ( Fig. 12 ) narrow. Labial segment I stoutest, not surpassing posterior margin of bucculae, apex of labium surpassing anterior margin of ventrite V to reaching or surpassing posterior margin of ventrite VI.

Pronotum ( Fig. 17 ). Pronotum more or less flattened; anterior half of pronotal disc slightly sloping and sometimes with prominent undulations or pit-like depressions; posterior half slightly convex or elevated. Anterior pronotal margin deeply incised to accommodate base of head, lacking collar; anterolateral angles rectangular, unarmed; lateral margin nearly straight or sometimes slightly concave medially, serrated,serrations prominent on anterolateral margin, compared to posterolateral margin. Humeri angulate, sometimes broadly angulate, prominent and slightly elevated; posterolateral margin of pronotum obliquely straight or medially slightly convex; posterior margin straight or slightly concave medially.

Scutellum ( Fig. 15 ) elongate triangular, longer than width at base, sides slightly convex in frenal portion; distal third abruptly narrowed; much shorter than anterodistal angles of corium; apex narrowly rounded; disc more or less uniformly and slightly convex to flat, sometimes slightly elevated at basal region.

Hemelytra Clavus narrowly triangular, corium laterally slightly convex, gradually widening posteriad. Membrane with reticulate venation, length variable.

Thoracic pleuron and sternum Prosternum and metasternum lacking carina, with indistinct median groove. Mesosternum lacking prominent longitudinal groove or keel but with obsolete longitudinal carina. External scent efferent system with peritreme spout-shaped (crescent-shaped) ( Fig. 91 ) usually not extending beyond middle of metapleuron; evaporatorium developed as roughly triangular and slightly elevated patch on metapleuron, encompassing ostiole and peritreme. Metathoracic spiracle long and well visible in ventral view.

Legs elongate, slender; femora cylindrical, unarmed. All tibiae unarmed, more slender than adjoining femora, outer surface with median longitudinal groove. All tarsi with segment II shortest, III as long as I; all tarsal segments dorsally regularly rounded, not grooved.

Pregenital abdomen. Connexivum wide, fully exposed dorsally, each ventrite with posterolateral angles angulate, not toothed. Abdominal venter convex, with prominent median, longitudinal groove. Ventrite II lacking spine or tubercle but with median longitudinal groove. Spiracle on ventrite II nearly exposed, only anterior margin covered by metapleuron, sometimes unexposed. A pair of trichobothria posteriad of spiracular line on each side of abdomen.

Male genitalia. Genital capsule roughly quadrangular; dorsal rim widely and concavely excavated; infoldings sublaterally with black, sclerotized teeth or minute tooth-like serrations; ventral rim concavely excavated; infoldings with or without a short, stout and narrow, inverted U-shaped (roughly tongue-like) median process ( Figs 22 , 30 , 43 , 78 ). Paramere roughly C-shaped, with short stem and expanded plate-like apodeme ( Figs 26 , 32 , 45 , 64 , 80 ). Crown with small, blunt and black tooth, sometimes continued as sclerotized, black ridge, position of tooth on crown varies. Phallus: articulatory apparatus with 1+1 roughly oval or irregular or quadrangular capitate processes ( Figs 96–99 ). Phallosoma sclerotized, constricted towards both ends, broadest medially and concave dorsally; two pairs of membranous conjunctival processes, dorsal pair with or without bifid apex, ventral pair shorter than or subequal to dorsal pair and apically rounded. Processes of aedeagus sclerotized, free or fused along midline at proximal half encompassing short, sclerotized aedeagus.

Female genitalia. Terminalia: valvifers VIII usually quadrangular, sometimes roughly triangular. Valvulae VIII with apical (= caudal) margin either uniformly rounded ( Figs 54 , 90 ) or slightly concave medially ( Figs 41 , 76 ). Valvifers IX fused to a single median transverse sclerite. Laterotergite IX distinctly shorter than apex of abdomen, caudal lateral margin of laterotergite VIII smooth and convex. Spermathecal duct expanded into single bulb-like dilation; apical receptacle orbicular with finger-like processes.

Remarks. Most of the structural characters such as length of mandibular plates with respect to clypeus, teeth in front of eyes, lengths of antennal segments, length of labium, serrations on lateral margins of pronotum, number and length of finger-like processes on spermathecal pump etc., show continuous variation within a given species. External colouration is also highly variable within a given species.

Figures

FIGURES 91–93. FIGURE 91. External scent efferent system showing peritreme and associated structures. FIGURES 92– 93. Genital capsule (caudal). 92, H. mudigerensis sp. nov.; 93, H. serrigera Westwood, 1837. Lettering: E—evaporatorium; Mf—median furrow; Mp—Metepimeral pseudosuture; Ms—metathoracic spiracle with filter process; O—Ostiole; Op— Ostiolar plate; P—Peritreme; t—tooth; ts—tooth like serrations.

FIGURES 10–17. Halys Fabricius, 1803.10, H. mudigerensis sp. nov. (head—dorsal);11, H. serrigera Westwood, 1837 (head—dorsal); 12, H. serrigera Westwood, 1837 (head—ventral); 13, H. shaista Ghauri, 1988 (head—dorsal); 14, H. sulcata (Thunberg, 1783) (head—dorsal); 15, H. mudigerensis sp. nov. (scutellum); 16, H. serrigera Westwood, 1837 (head—lateral); 17, H. mudigerensis sp. nov. (pronotum). Lettering: at—antenniferous tubercle; b—bucculae; lr—labrum; mt—tooth on lateral margin of mandibular plates.

FIGURES 21–28. Cimex dentatus Fabricius, 1775 (Lectotype)—male genitalia. 21, genital capsule (dorsal); 22, genital capsule (ventral); 23–26, paramere (different views); 27, phallus (dorsal); 28, phallus (ventral). Courtesy of H. Enghoff and A. Illum, ©Natural History Museum of Denmark. Lettering: mp—median process; t—tooth on parameral crown.

FIGURES 29–35. H. mudigerensis sp. nov.—male genitalia. 29, genital capsule (dorsal); 30, genital capsule (ventral); 31, genital capsule (caudal); 32, paramere (ventral); 33, paramere (dorsal); 34, paramere (lateral); 35, articulatory apparatus. Lettering: bcl—bifid caudal lobes; cp—capitate processes; mp—median process; t—tooth.

FIGURES 42–48. H. serrigera Westwood, 1837—male genitalia. 42, genital capsule (dorsal); 43, genital capsule (ventral); 44, genital capsule (caudal); 45, paramere (dorsal); 46, paramere (dorsolateral); 47, paramere (ventral); 48, articulatory apparatus. Lettering: cp—capitate processes; mp—median process; t—tooth.

FIGURES 77–83. H. sulcata (Thunberg, 1783)—male genitalia. 77, genital capsule (dorsal); 78, genital capsule (ventral); 79, genital capsule (caudal); 80, paramere (dorsal); 81, paramere (ventrolateral); 82, paramere (ventral); 83, articulatory apparatus. Lettering: cp—capitate processes; mp—median process; t—tooth.

FIGURES 61–68. H. shaista Ghauri, 1988—male genitalia. 61, genital capsule (dorsal); 62, genital capsule (ventral); 63, genital capsule (caudal); 64, paramere (dorsal); 65, paramere (dorsolateral); 66, paramere (ventral); 67, articulatory apparatus; 68, phallus without articulatory apparatus (ventral).

FIGURES 94–99. FIGURES 94–95. Genital capsule (caudal). 94, H. shaista Ghauri, 1988; 95, H. sulcata (Thunberg, 1783). Lettering: t—tooth; ts—tooth like serrations. FIGURES 96–99. Capitate processes. 96, H. mudigerensis sp. nov.; 97, H. serrigera Westwood, 1837; 98, H. shaista Ghauri, 1988; 99, H. sulcata (Thunberg, 1783)

FIGURES 49–56. H. serrigera Westwood, 1837—male and female genitalia. 49, phallus (ventral); 50, phallus (dorsal); 51–52, phallus (lateral); 53, spermatheca; 54, valvulae VIII; 55, female terminalia (before digestion); 56, female terminalia (after digestion). Lettering: ad—aedeagus; cp—capitate processes; dcp—dorsal conjunctival process; pa—processes of aedeagus; lt VIII—laterotergite VIII; lt IX— laterotergite IX; sp—spermathecal pump; vlf VIII—valvifers VIII; vlf IX—valvifers IX.

FIGURES 84–90. H. sulcata (Thunberg, 1783)—male and female genitalia. 84, phallus (dorsal); 85, phallus (ventral); 86, phallus (lateral); 87, spermatheca; 88, female terminalia (before digestion); 89, female terminalia (after digestion); 90,valvulae VIII.

FIGURES 36–41. H. mudigerensis sp. nov.—male and female genitalia. 36, phallus (dorsal); 37, phallus (ventral); 38, phallus (lateral); 39, spermatheca; 40, female terminalia; 41,valvulae VIII. Lettering: dcp—dorsal conjunctival processes; lt VIIIlaterotergite VIII; lt IX—laterotergite IX; pa—processes of aedeagus; sp—spermathecal pump; vcp—ventral conjunctival process; vlf VIII—valvifers VIII; vlf IX—valvifers IX.

FIGURES 69–76. H. shaista Ghauri, 1988—male and female genitalia. 69, phallus (dorsal); 70, phallus (ventral); 71–72, phallus (lateral); 73, spermatheca; 74, female terminalia (before digestion); 75, female terminalia (after digestion); 76, valvulae VIII.