Rhyacobates malaisei 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 : 51-52

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.10064069
persistent identifier	https://treatment.plazi.org/id/045E878D-FFEE-2908-3A19-FD6C74A308BD
treatment provided by	Plazi
scientific name	Rhyacobates malaisei Andersen & Chen, 1995
status

Treatment

Rhyacobates malaisei Andersen & Chen, 1995 View in CoL

Figs 3M View Fig , 4J View Fig , 5L View Fig , 7C View Fig , 8I View Fig , 30 View Fig

Rhyacobates malaisei Andersen & Chen, 1995: 59–61 View in CoL , figs 18–61 (original description).

Diagnosis

Body length of apterous females 7.00–9.82, of apterous males 6.00–6.81. Female: pronotum mainly black with a median subtriangular brownish-yellow spot; mesonotum mainly black with a median brownish-yellow stripe; metanotum completely black, without median yellow stripe; connexiva erect on abdominal segments I–VI, parallel to each other above mediotergites, curved mesad over mediotergite VII ( Fig. 30A View Fig ), meeting in middle of abdominal dorsum ( Fig. 30D View Fig ) or overlapping each other ( Fig. 30E View Fig ); abdominal segment VII dorsally with a long process terminating each connexivum ( Fig. 30F View Fig ), posterior margin of the long process with dense setae; abdominal segment VII laterally with a pair of small, pointed processes ( Fig. 30G View Fig ); posterior margin of sternum VII truncate or slightly sunken, without median process ( Fig. 30F View Fig ). Male: median black spot of head posteriorly bifurcate and extending to the hind margin of head; pronotum mainly black with a median subtriangular brownish-yellow spot; middle trochanter without spines; middle femur with scattered small spines, not arranged in distinct row ( Fig. 30J View Fig ); length of middle tibia ca 2.0–2.1 times length of hind tibia; proctiger widened, with angular lateral lobes produced into small process directing postero-ventrad ( Figs 7C View Fig , 30K View Fig ); paramere relatively slender and evenly curved, apex slightly spatulate ( Figs 8I View Fig , 30L View Fig ).

Material examined

Non-type specimens

CHINA – Yunnan Province • 1 ♁, 4 ♀♀ (apterous); An-ning City , Qing-long County; 25°0′58.1″ N, 102°19′35.2″ E; 790 m a.s.l.; 28 Jun. 2016; Hua-xi Liu leg.; NKUM GoogleMaps • 7 ♁♁, 8 ♀♀ (apterous); Da-li City ; Yang-bi County; 25°42′25.3″ N, 99°56′49.8″ E; 1500 m a.s.l.; 20 Aug. 2006; Xu Zhang leg.; NKUM GoogleMaps • 2 ♁♁ (apterous); Kun-ming City; Mu-yang River ; 23°4′4.7″ N, 113°12′15.0″ E; 2041 m a.s.l.; 3 Oct. 2022; Xun Hao leg.; NKUM GoogleMaps .

Supplemental description

Apterous female

MEASUREMENTS. Body length 7.00–9.82, width 2.10–2.88, head width 1.48, interocular width 0.75, eye length (dorsal view) 0.53; relative lengths of antennal segments I–IV: 3.88: 1.03: 1.35: 0.91; pronotum: length 0.80, width 1.68; mesonotum: length 2.53, width 2.88; metanotum: length 0.78, width 2.44; abdomen length (ventral view) 4.83; abdominal sternum VII: length 1.96, width 1.51; abdominal mediotergite I: length 0.46, width 1.38; relative lengths of leg segments (femur: tibia: tarsal segment I: tarsal segment II): fore leg: 3.85: 3.15: 1.52:0.85, middle leg: 10.85: 5.91: 2.53:0.34, hind leg: 10.91:3.47: 0.19: 0.20.

COLORATION. Median black spot of head posteriorly bifurcate. Pronotum mainly black with a median subtriangular brownish-yellow spot. Mesonotum mainly black with a median brownish-yellow stripe. Metanotum chiefly black, without yellow markings ( Figs 3M View Fig , 30A View Fig ). Connexivum dorsally blackish. Venter of female chiefly blackish with a median yellowish spot ( Fig. 30B View Fig ). Abdominal venter light yellow.

ABDOMEN. Abdomen elongate, nearly straight, moderately curved dorsad towards end ( Fig. 30C View Fig ). Connexiva erect on abdominal segments I–VI, parallel to each other above mediotergites, reflexed over abdominal mediotergite VII ( Fig. 30A View Fig ), meeting in middle of abdominal dorsum ( Fig. 30D View Fig ) or overlapping each other ( Fig. 30E View Fig ). Abdominal segment VII elongate, nearly as long as two preceding abdominal segments together ventrally ( Figs 5L View Fig , 30C View Fig ), completely enclosing genital segments ( Fig. 30D–E View Fig ). Abdominal segment VII dorsally with a long process terminating each connexivum ( Fig. 30F View Fig ), posterior margin of the long process with dense setae. Abdominal segment VII laterally with a pair of small, pointed processes ( Fig. 30G View Fig ), posterior margin of sternum VII truncate or slightly sunken, without median process ( Fig. 30F View Fig ).

Apterous male

MEASUREMENTS. Body length 6.00–6.81, width 1.70–1.98, head width 1.21, interocular width 0.54, eye length (dorsal view) 0.48; relative lengths of antennal segments I–IV: 3.58: 0.89: 1.23:0.72; pronotum: length 0.69, width 1.32; mesonotum: length 1.91, width 1.98; metanotum: length 0.42, width 1.73; abdomen length (ventral view) 2.57; abdominal sternum VII: length 0.43, width 0.66; abdominal mediotergite I: length 0.25, width 0.62; relative lengths of leg segments (femur: tibia: tarsal segment I: tarsal segment II): fore leg: 3.54:3.01: 1.03: 0.54, middle leg: 10.11: 5.03:2.75: 0.31, hind leg: 10.56:2.56: 0.13: 0.16.

C OLORATION. Median black spot of head posteriorly bifurcate and extending to the hind margin of head. Pronotum mainly black with a median brownish-yellow spot, which is subtriangular-shaped. Pronotum mainly black with a median brownish-yellow spot. Mesonotum mainly black with a median brownish-yellow stripe. Metanotum chiefly black, without yellow markings ( Figs 4J View Fig , 30H View Fig ). Connexivum dorsally blackish. Mesosternum mainly blackish with a median brownish small spot ( Fig. 30I View Fig ). Abdominal venter dark-brownish.

ABDOMEN. Abdominal mediotergite I not swollen, fully covered with silvery pubescence.

LEG. Middle trochanter without spines; middle femur with scattered small spines, not arranged in distinct row ( Fig. 30J View Fig ).

GENITALIA. Abdominal segment VIII ventro-laterally impressed. Pygophore large, ovate. Proctiger widened, with angular lateral lobes produced into small process directed postero-ventrad ( Figs 7C View Fig , 30K View Fig ). Paramere relatively slender and evenly curved, apex slightly spatulate ( Figs 8I View Fig , 30L View Fig ).

Distribution

China: Yunnan; Thailand: Chiang Mai; Myanmar: Bumgahtuang-Hpungan ( Andersen & Chen 1995).

Comparative notes

Rhyacobates malaisei is most similar to R. gongvo ; see comparative notes under R. gongvo .