Cybister (Neocybister) puncticollis ( Brulle , 1837)

Miller, Kelly B., Michat, Mariano C. & Ferreira Jr, Nelson, 2024, Reclassification of Cybistrinae Sharp, 1880 in the Neotropical Region (Coleoptera, Adephaga, Dytiscidae), with description of new taxa, ZooKeys 1188, pp. 125-168 : 125

Cybister (Neocybister) puncticollis ( Brulle, 1837)

Figs 10 , 17 , 18 , 33-35 , 52 , 59

Dyticus puncticollis Brullé, 1837: 46.

Cybister puncticollis : Aubé 1838: 52.

Trogus puncticollis : Gemminger and Harold 1868: 460.

Megadytes puncticollis : Sharp 1882: 709; van den Branden 1885: 29; Regimbart 1889: 267; 1904: 225; Chatanay 1910: 434; Bruch 1915: 479; Zimmermann 1919: 235; 1920: 256; Wilke 1921: 24; Bruch 1927: 543; Blackwelder 1944: 80; Brinck 1945: 8; Mouchamps 1957: 283; Trémouilles and Bachmann 1980: 105.

Cybister (Meganectes) kemneri Brinck, 1945: 18; Trémouilles and Bachmann 1980: 105.

Cybister (Meganectes) puncticollis : Trémouilles and Bachmann 1980: 105.

Cybister (Neocybister) puncticollis : Miller et al. 2007: 54; Nilsson and Hájek 2023: 84.

Type locality.

Cybister puncticollis : Bolivia, San Miguel. Cybister kemneri : Brazil, La Plata, Amazonas, Rio Autaz.

Type specimen.

Cybister puncticollis , in MNHN (not examined). Cybister kemneri , in MZLU (not examined).

Diagnosis.

This species is larger (Fig. 10 ) than the other Neotropical species in the genus, C. festae (Fig. 9 ) and the male genitalia are distinctly different (Figs 33-35 ). See above under that species for details about this and additional diagnostic differences between these two species of Cybister .

Description.

Measurements. TL = 26.6-27.6 mm, GW = 15.0-15.9 mm, PW = 10.8-11.6 mm, HW = 6.5-6.8 mm, EW = 3.7-3.8 mm, TL/GW = 1.7-1.8, HW/EW = 1.7-1.8, WC/WV = 2.9-3.2. Body shape oval, widest slightly posterad of middle; lateral margins broadly curved, continuously curved between pronotum and elytron. Depressed and somewhat flattened in lateral aspect.

Coloration. Head dark green, clypeus and labrum pale yellow. Pronotum dark green, with broad lateral yellow marginal band (Fig. 10 ), medial margin of band distinctly delimited, band separated from posterolateral margin by narrow green strip (Fig. 10 ). Elytron dark green with broad lateral yellow marginal band, medial margin of band distinctly delimited, lateral margin of band slightly remote from lateral elytral margin for medial portion of length, extending laterally to margin of elytron anteriorly and posteriorly, apex of yellow band diffusing into coloration of elytron, less distinct (Fig. 10 ). Ventral surfaces mostly black except antennae and palpi orange, pro- and mesothoracic legs mostly orange, tarsi dark orange, metathoracic legs testaceous, anterodorsal surface of tibia orange, propleuron and elytral epipleuron pale orange to testaceous, and with small orange maculae laterally on abdominal ventrites IV-VI.

Sculpture and structure. Head broad, anteriorly produced, eyes prominent; dorsal surface evenly covered with exceptionally fine micropunctures but smooth and shiny. Pronotum with lateral margins evenly and shallowly curved; surface of pronotum similar to surface of head in micropunctation; pronotum dorsally evenly curved. Elytron with margins very broadly curved, more strongly curved posteriorly; surface similar to surface of head in micropunctation and surface appearance. Prosternal process anteriorly distinctly emarginate medially, remaining surface nearly flat throughout and moderately broad, apex broadly elongate and sharply pointed. Metaventral wing narrow (WC/WV = 2.9-3.2); surface smooth, with extremely fine microsculpture, shiny. Lateral portion of metacoxa large, broad, surface smooth and shiny, with extremely fine microsculpture; metacoxal lines short and curved, extending anteriorly less than half distance across metacoxa. Abdominal ventrites smooth, relatively unsculptured.

Male genitalia. Male median lobe in lateral aspect moderately slender throughout, evenly curved, apically abruptly expanded with a narrowly rounded apex, ventral sclerite slender and evenly curved basally, apically straight and apically pointed (Fig. 33 ); in dorsal aspect median lobe moderately broad basally, lateral margins broadly sinuate, apex broadly expanded, with apex broadly sub-truncate, medially broadly pointed (Fig. 34 ). Lateral lobe moderately broad throughout length, evenly curved, apex narrowly rounded, with long series of setae along dorsal margin (Fig. 35 ).

Female genitalia. Vagina extremely elongate, slender; with enlarged area at base of common oviduct and spermatheca, with enlarged lateral sacs on this enlarged area; spermatheca extremely slender and elongate (Fig. 59 ); gonocoxae together slender and apically pointed (Fig. 59 ); gonocoxosternite broad, anterolateral lobe broad, medial margin distinctly, narrowly emarginate, basomedially with field of setae (Fig. 59 ).

Sexual dimorphism. Males have a broad protarsal palette with ventral adhesive setae with apical structures in the form of elongate flattened spatulate surfaces; males also have mesotarsomeres with posteroventral fields of setae which are absent in females. Females lack natatory setae along the ventral margins of the metatarsomeres, but these are present in males. Males have a single metatarsal claw (the anterior claw, Fig. 17 ), whereas females have a second, posterior claw that is ~ 1/2 the length of the anterior, is abruptly curved apically and sharply pointed (Fig. 18 ).

Variation. Specimens vary somewhat in size and coloration, with some specimens more greenish and others darker, less greenish.

Distribution.

This species is known from Argentina, Bolivia, Brazil, French Guyana, and Peru. There is also a previously unpublished record from Paraguay.

Material examined.

Specimens were examined from Argentina, Bolivia, Peru, and Paraguay.

Figures

Figures 9 - 14. Neotropical Cybistrinae species, habitus 9 Cybister festae 10 Cybister puncticollis 11 Nilssondytes diversus 12 Megadytes parvus 13 Megadytes latus 14 species " IR 57 " (Ribera et al. 2008). Scale bar: 10.0 mm.

Figures 15 - 29. Neotropical Cybistrinae species, metatarsal claws and tarsomere VI of males and females 15, 16 Cybister festae 17, 18 Cybister puncticollis 19, 20 Nilssondytes diversus 21, 22 Megadytes latus 23, 24 Megadytes parvus 25 species " IR 57 " (Ribera et al. 2008) 26, 27 Paramegadytes glaucus 28, 29 Metaxydytes fraternus. Scale bars: 1.0 mm.

Figures 30 - 50. Neotropical Cybistrinae species, male genitalia 30 - 32 Cybister festae: 30 median lobe, right lateral aspect 31 median lobe, ventral aspect 32 right lateral lobe, right lateral aspect 33 - 35 Cybister puncticollis: 33 median lobe, right lateral aspect 34 median lobe, ventral aspect 35 right lateral lobe, right lateral aspect 36 - 38 Nilssondytes diversus: 36 median lobe, right lateral aspect 37 median lobe, ventral aspect 38 right lateral lobe, right lateral aspect 39 - 43 Megadytes parvus: 39 median lobe, right lateral aspect 40 median lobe, ventral aspect 41 right lateral lobe, right lateral aspect 42 apex of median lobe, right lateral aspect 43 apex of median lobe, ventral aspect 44 - 47 Megadytes latus: 44 median lobe, right lateral aspect 45 median lobe, ventral aspect 46 right lateral lobe, right lateral aspect 47 apex of median lobe, ventral aspect 48 - 50 species " IR 57 " (Ribera et al. 2008): 48 median lobe, right lateral aspect 49 median lobe, ventral aspect 50 right lateral lobe, right lateral aspect.

Figures 51 - 57. Neotropical Cybistrinae species, male sternite IX, ventral aspect 51 Cybister festae 52 Cybister puncticollis 53 Nilssondytes diversus 54 Megadytes latus 55 Megadytes parvus 56 Paramegadytes glaucus 57 Metaxydytes fraternus. Scale bars: 1.0 mm.

Figures 58 - 61. Neotropical Cybistrinae species, female genitalia including left gonocoxosternite, ventral aspect, except Fig. 60 without internal genitalia 58 Cybister festae 59 Cybister puncticollis 60 Megadytes latus 61 Nilssondytes diversus. Scale bars: 1.0 mm.