Rhyacobates scorpio 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 : 56-60

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.8385656

persistent identifier

https://treatment.plazi.org/id/045E878D-FFEB-2900-3A13-FADC733609C7

treatment provided by

Plazi

scientific name

Rhyacobates scorpio Andersen & Chen, 1995
status

 

Rhyacobates scorpio Andersen & Chen, 1995 View in CoL

Figs 2D View Fig , 3O View Fig , 4L View Fig , 5N View Fig , 7E View Fig , 8K View Fig , 32–33 View Fig View Fig

Rhyacobates scorpio Andersen & Chen, 1995: 62–63 View in CoL , figs 1, 28–32 (original description).

Diagnosis

Body length of apterous females 9.22–11.95, of apterous males 8.01–8.10. Female: pronotum mainly black with a median brownish-yellow spot; mesonotum and metanotum mainly black with a median brownish-yellow stripe ( Figs 2D View Fig , 3O View Fig , 32A View Fig , 33A View Fig ); abdominal segments I–VI straight, with long, blackish setae on mesal margins of the connexivum; abdominal segment VII elongate, abruptly bent dorsad at an angle of about 90° ( Figs 5N View Fig , 33C View Fig ), dorsally with an angular process terminating each connexivum ( Fig. 33D–F View Fig ), posterior margin of sternum VII angularly produced in the middle ( Fig. 33G View Fig ). Male: middle trochanter with 3–5 spines; middle femur with spines but not in distinct row ( Fig. 33J View Fig ); length of middle tibia ca 1.2–1.4 times length of hind tibia; proctiger relatively large, with broadly rounded lobes laterally ( Figs 7E View Fig , 33K View Fig ); paramere relatively slender, strongly curved at basal fourth, distal part tapering towards hook-shaped apex ( Figs 8K View Fig , 33L View Fig ).

Material examined

Holotype ( Fig. 32A–C View Fig )

CHINA • ♀ (apterous); Sichuan Province, Song Ch′i Hsien ; Jul. 1938; D.C. Graham leg.; USNM .

Paratypes ( Fig. 32D–G View Fig )

CHINA – Sichuan Province • 2 ♁♁, 1 ♀ (apterous); E-mei Mountain, Jie-yin Temple; 14 Jul. 1957; Le-yi Zheng leg.; NKUM 1 ♀ (apterous); Song Ch′i, Kuanhsien; Aug. 1938; D.C. Graham leg.; USNM 1 ♀ (apterous); Wenchuan City; Aug. 1938; D.C. Graham leg.; USNM .

Non-type specimens

CHINA – Sichuan Province • 1 ♁, 1 ♀ (apterous); E-mei-shan City, E-mei Mountain, Qingyin Attic ; 29°34′29.7″ N, 103°24′38.3″ E; 19 Aug. 2013; Zhen Ye leg.; NKUM GoogleMaps 5 ♁♁, 11 ♀♀ (apterous); Le-shan City, Mu-chuan County, Hei-xiong Valley ; 28°52′26.8″ N, 103°57′31.1″ E; 1090 m a.s.l.; 2 Aug. 2017; Chen-guang Zheng leg.; NKUM GoogleMaps 2 ♁♁, 10 ♀♀ (apterous); Ya-an City, Bi-xia Mountain ; 30°4′8.9″ N, 102°59′34.6″ E; 30 Jul. 2016; Chen-guang Zheng leg.; NKUM GoogleMaps .

Supplemental description

Apterous female

MEASUREMENTS. Body length 9.22–11.95, width 3.31–3.81, head width 1.83, interocular width 0.84, eye length (dorsal view) 0.78; relative lengths of antennal segments I–IV: 4.85: 1.51:1.83:1.29; pronotum: length 1.02,width 2.08;mesonotum: length2.97, width 3.81; metanotum:length 1.25,width 3.28;abdomen length (ventral view) 5.06; abdominal sternum VII: length 1.53, width 1.58; abdominal mediotergite I: length 0.63, width 1.63; relative lengths of leg segments (femur:tibia: tarsal segment I:tarsal segment II): fore leg: 5.15: 4.59:2.23:1.32, middle leg: 14.15:8.52: 5.32: 0.59, hind leg: 14.31:7.92:0.21:0.28.

C OLORATION. 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 2D View Fig , 3O View Fig , 32A View Fig , 33A View Fig ). Connexivum dorsally brownish-yellow. Abdominal tergum I with a median yellow marking. Mesosternum chiefly blackish with two median yellowish spots, divided by a blackish line ( Fig. 33B View Fig ). Abdominal venter light yellow.

ABDOMEN. Abdomen relatively short, gradually tapering towards apex ( Fig. 33C View Fig ). Connexiva on abdominal segments I–VI erect, not meeting each other above mediotergites, reflexed upon abdominal mediotergite VII ( Fig. 33A View Fig ). Abdominal segment VII elongate, completely enclosing genital segments, nearly as long as two preceding abdominal segments together, abruptly turning dorsad at a maximum angle of about 90°, dorsally with an angular process terminating each connexivum ( Fig. 33D–F View Fig ), posterior margin of sternum VII angularly produced in the middle ( Fig. 33G View Fig ).

Dealated macropterous female

Similar to apterous female in general structure and coloration with following exceptions: thorax with a pronotal lobe, anterior part with a subrhombic yellow marking, posterior part elongate, covering most of mesonotum; posterior margin broadly rounded and brownish; abdominal segment VII only weakly turned dorsad.

MEASUREMENTS. Body length 11.31, width 3.58, head width 1.64, interocular width 0.84, eye length (dorsal view) 0.73; relative lengths of antennal segments I–IV: 4.63:1.34: 1.62: 1.22; pronotum: length 4.61, width 2.81; mesonotum width 3.58; metanotum: length 0.85, width 3.23; abdomen length (ventral view) 4.68; abdominal sternum VII: length 2.15, width 1.63; abdominal mediotergite I: length 0.66, width 1.17; relative lengths of leg segments (femur:tibia: tarsal segment I:tarsal segment II): fore leg: 4.68:4.28:1.98: 1.15, middle leg: 12.70: 7.26: 3.76:0.58, hind leg: 13.56:6.78: 0.18: 0.29.

Apterous male

MEASUREMENTS. Body length 8.01–8.10, width 1.60–2.81, head width 1.66, interocular width 0.83, eye length (dorsal view) 0.64; relative lengths of antennal segments I–IV: 4.62: 1.48: 1.70: 1.18; pronotum: length 0.91, width 1.83; mesonotum: length 2.38, width 2.81; metanotum: length 0.91, width 2.41; abdomen length (ventral view) 3.72; abdominal sternum VII: length 0.54, width 1.34; abdominal mediotergite I: length 0.41, width 1.06; relative lengths of leg segments (femur: tibia: tarsal segment I: tarsal segment II): fore leg: 5.16:4.40: 1.44: 0.70, middle leg: 13.02:7.44: 3.78: 0.59, hind leg: 13.35: 6.13: 0.19: 0.29.

C OLORATION. Median black spot of head posteriorly bifurcate. Pronotum mainly black with a median brownish-yellow spot. Mesonotum mainly black with a median brownish-yellow stripe. Metanotum chiefly blackish, without yellow markings ( Figs 4L View Fig , 33H View Fig ). Connexivum dorsally blackish. Mesosternum chiefly blackish with median brownish spots or totally blackish ( Fig. 33I View Fig ). Abdominal venter dark-yellow.

LEG. Middle trochanter with 3–5 spines on distal part; middle femur with spines but not in distinct row ( Fig. 33J View Fig ).

GENITALIA. Abdominal segment VIII ventro-laterally impressed. Pygophore large, ovate. Proctiger relatively large, with broadly rounded lobes laterally ( Figs 7E View Fig , 33K View Fig ). Paramere relatively long and slender, strongly curved at basal fourth, distal part tapering towards hook-shaped apex ( Figs 8K View Fig , 33L View Fig ).

Dealated macropterous male

Similar to apterous female in general structure and coloration with following exceptions: thorax with a pronotal lobe, anterior part with a subrhombic yellow marking, posterior part elongate, covering most of mesonotum; posterior margin broadly rounded and brownish.

MEASUREMENTS. Body length 8.35, width 2.78, head width 1.57, interocular width 0.78, eye length (dorsal view) 0.61; relative lengths of antennal segments I–IV: 4.52: 1.43: 1.61:1.18; pronotum: length 3.20, width 2.51; mesonotum width 2.78; metanotum width 2.46; abdomen length (ventral view) 2.90; abdominal sternum VII: length 0.51, width 1.33; abdominal mediotergite I: length 0.44, width 1.09; relative lengths of leg segments (femur:tibia: tarsal segment I: tarsal segment II): fore leg: 4.85: 4.05: 1.38: 0.95, middle leg: 13.01: 7.55:3.98: 0.54, hind leg: 13.45:6.19: 0.15: 0.23.

Distribution

China: Sichuan ( Andersen & Chen 1995).

Comparative notes

The female of R. scorpio can be distinguished from that of all other species of Rhyacobates by the unique shape of its abdomen ( Figs 5N View Fig , 33C View Fig ): abdominal segments I–VI are straight, with long, blackish setae on the lateral margins of the connexivum; abdominal segment VII is elongate, and abruptly turns dorsad at a maximum angle of about 90°, dorsally with an angular process terminating each connexivum ( Fig. 33D–F View Fig ), ventrally with a median process ( Fig. 33G View Fig ).

USNM

Smithsonian Institution, National Museum of Natural History

NKUM

Nankai University

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Hemiptera

SubOrder

Heteroptera

InfraOrder

Gerromorpha

SuperFamily

Gerroidea

Family

Gerridae

SubFamily

Ptilomerinae

Genus

Rhyacobates

Loc

Rhyacobates scorpio Andersen & Chen, 1995

Leng, Zhaoqi, Tran, Anh Duc & Ye, Zhen 2023
2023
Loc

Rhyacobates scorpio

Andersen & Chen 1995: 62 - 63
1995
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