Rhyacobates recurvus Andersen & Chen, 1995

Leng, Zhaoqi, Tran, Anh Duc & Ye, Zhen, 2023, Taxonomic review of Rhyacobates Esaki, 1923, with descriptions of three new species (Hemiptera: Heteroptera: Gerridae), European Journal of Taxonomy 893 (1), pp. 1-73 : 54-56

publication ID	https://doi.org/ 10.5852/ejt.2023.893.2285
publication LSID	lsid:zoobank.org:pub:D9DA4879-BC1D-4947-96E8-7D574DE334BA
DOI	https://doi.org/10.5281/zenodo.8385650
persistent identifier	https://treatment.plazi.org/id/045E878D-FFE9-290C-3A1C-FEBA74D10A5D
treatment provided by	Plazi
scientific name	Rhyacobates recurvus Andersen & Chen, 1995
status

Treatment

Rhyacobates recurvus Andersen & Chen, 1995 View in CoL

Figs 3N View Fig , 4K View Fig , 5M View Fig , 7D View Fig , 8J View Fig , 14 View Fig , 31 View Fig

Rhyacobates recurvus Andersen & Chen, 1995: 59 View in CoL , figs 16–17 (original description).

Diagnosis

Body length of apterous females 7.06–8.71, of apterous males 5.42–5.91. Female: pronotum mainly black with a median brownish-yellow spot; mesonotum and metanotum mainly black with a median brownish-yellow stripe ( Figs 3N View Fig , 31A View Fig ); abdomen relatively short, with posterior part distinctly curved dorsad to oblique or nearly vertical position ( Figs 8J View Fig , 31C View Fig ); abdominal mediosternite VII tapering caudad, posterior margin with a median process; apex of the process pointed and hook-shaped ( Fig. 31D, F View Fig ). Male: middle trochanter with one spine; middle femur with scattered small spines, not arranged in distinct row ( Fig. 31I View Fig ); length of middle tibia ca 1.6 times length of hind tibia; proctiger laterally with rounded lobes ( Figs 7D View Fig , 31J View Fig ); paramere relatively slender, strongly curved at basal fourth, middle part thickened, distal part tapering towards narrowly rounded apex ( Figs 8J View Fig , 31J View Fig ).

Material examined

Non-type specimens

CHINA – Hubei Province • 7 ♁♁, 5 ♀♀ (apterous); Huang-gang City, Ying-shan County, Jiu-gong Mountain ; 29°3′25.6″ N, 107°5′55.1″ E; 130 m a.s.l.; 11 Jul. 2022; Zhao-qi Leng and Zhen Ye leg.; NKUM GoogleMaps . – Jiangxi Province • 1 ♁, 2 ♀♀ (apterous); Nan-chang City ; 2 Jun. 1919; IZAS . – Zhejiang Province • 3 ♀♀ (apterous); Jin-hua City, Pan-an County, Da-pan Mountain ; 28°58′30.1″ N, 120°31′36.4″ E; 29 Jul. 2015; Wen-bo Yi leg.; NKUM GoogleMaps .

Supplemental description

Apterous female

MEASUREMENTS. Body length 7.06–8.71, width 2.63–2.90, head width 1.42, interocular width 0.53, eye length (dorsal view) 0.60; relative lengths of antennal segments I–IV: 3.95: 1.05:0.93:0.78; pronotum: length 0.74, width 1.52;mesonotum: length2.44, width 2.63; metanotum:length 0.69, width 2.34; abdomen length (ventral view) 1.96; abdominal sternum VII: length 0.90, width 1.12; abdominal mediotergite I: length 0.28, width 1.09; relative lengths of leg segments (femur:tibia: tarsal segment I:tarsal segment II): fore leg: 4.10: 3.65:1.67:0.83, middle leg: 12.02:6.95: 2.91: 0.38, hind leg: 12.35:5.05:0.16:0.18.

COLORATION. Median black spot of head posteriorly bifurcate. Pronotum mainly black with a median brownish-yellow spot. Mesonotum and metanotum mainly black with a median brownish-yellow stripe ( Figs 3N View Fig , 31A View Fig ). Abdominal tergum I with yellowish spots on each side or completely yellow. Connexivum dorsally brownish-yellow. Mesosternum chiefly blackish with a median subtriangular yellowish spot ( Fig. 31B View Fig ). Abdominal venter light yellow.

ABDOMEN. Abdomen relatively short, with posterior part distinctly curved dorsad to oblique or nearly vertical position ( Figs 5M View Fig , 31C View Fig ). Connexiva erect on abdominal segments I–II, converging along dorsal midline of segments III–VI, reflexed above terminal terga ( Fig. 31A View Fig ). Abdominal segment VII elongate, ventral margin longer than dorsal margin in lateral view ( Figs 5M View Fig , 31C View Fig ), nearly as long as three preceding abdominal segments together, not completely enclosing genital segments ( Fig. 31D View Fig ); laterosternites of connexivum VII expanded dorsad, folded mesad ( Fig. 31A View Fig ), meeting in middle of abdominal dorsum or overlapping each other ( Fig. 31E View Fig ). Abdominal sternum VII tapering caudad, posterior margin with a median process; apex of the process pointed and hook-shaped ( Fig. 31D, F View Fig ).

Apterous male

MEASUREMENTS. Body length 5.42–5.91, width 1.73–2.01, head width 1.23, interocular width 0.41, eye length (dorsal view) 0.49; relative lengths of antennal segments I–IV: 2.93: 0.93: 0.97: 0.73; pronotum: length 0.64, width 1.27; mesonotum: length 1.78, width 1.83; metanotum: length 0.63, width 1.73; abdomen length (ventral view) 1.91; abdominal sternum VII: length 0.42, width 0.79; abdominal mediotergite I: length 0.21, width 0.56; relative lengths of leg segments (femur: tibia: tarsal segment I: tarsal segment II): fore leg: 3.08: 2.64: 0.88: 0.54, middle leg: 9.64: 4.87: 2.17: 0.32, hind leg: 10.06: 3.10: 0.13: 0.16.

COLORATION. Median black spot of head posteriorly bifurcate. Mesonotum mainly black with a median brownish-yellow stripe. Metanotum chiefly blackish, without yellow markings ( Figs 4K View Fig , 31G View Fig ). Connexivum dorsally blackish. Mesosternum chiefly blackish with a median subtriangular yellowish spot, narrower than that of female ( Fig. 31H View Fig ). Abdominal venter light yellow.

LEG. Middle trochanter with one spine; middle femur with scattered small spines, not arranged in distinct row ( Fig. 31I View Fig ).

GENITALIA. Abdominal segment VIII ventro-laterally impressed. Pygophore large, ovate. Proctiger with rounded lobes laterally ( Figs 7D View Fig , 31J View Fig ). Paramere relatively slender, strongly curved at basal fourth, middle part thickened, distal part tapering towards narrowly rounded apex ( Figs 8J View Fig , 31J View Fig ).

Distribution

China: Hubei, Zhejiang (first records); Jiangxi ( Andersen & Chen 1995).

Comparative notes

Rhyacobates recurvus is most similar to R. turgidus sp. nov.; see comparative notes under R. turgidus .

Remarks

Andersen & Chen (1995) described this species based on a single female specimen from Jiangxi, China. In this study, we have collected both males and females from Hubei and Zhejiang, China; thus, we can provide a description of the apterous male and additional distribution information.