Gyrinus (Neogyrinus) ovatus Aubé, 1838, Aube, 1838

Gustafson, Grey T. & Short, Andrew E. Z., 2017, Review of the whirligig beetle genus Gyrinus of Venezuela (Coleoptera: Gyrinidae), Acta Entomologica Musei Nationalis Pragae 57 (2), pp. 479-520: 493-497

publication ID

http://doi.org/ 10.1515/aemnp-2017-0087

publication LSID

lsid:zoobank.org:pub:EC4E5771-9B5E-4745-BB24-556963D657B7

DOI

http://doi.org/10.5281/zenodo.5414968

persistent identifier

http://treatment.plazi.org/id/03959737-FFFA-2034-118E-8CD9FD486B07

treatment provided by

Marcus

scientific name

Gyrinus (Neogyrinus) ovatus Aubé, 1838
status

 

Gyrinus (Neogyrinus) ovatus Aubé, 1838  

( Figs 3, 7–9, 20–21, 29, 53, 64–67, 74, 78)

Gyrinus ovatus Aubé, 1838: 708   (original description). Gyrinus (Neogyrinus) ovatus: OCHS (1935a)   : 126 (new status). Gyrinus (Neogyrinus) racenisi Ochs, 1953: 188   (original description), syn. nov. Neogyrinus ovatus: CRESPO (1989)   : 239 (new combination).

Type localities. Gyrinus ovatus   : ‘ Brésil et Cayenne’ [ Brazil and Cayenne region, French Guiana]. Gyrinus racenisi   : ‘Espino, Est. Guárico’ [ Venezuela].

Type material. Gyrinus ovatus   : not studied, type depository unknown.

Gyrinus racenisi   : PARATYPE: ♀ ( Fig. 78), ‘ ♀ [beige label, typed black ink]’ ‘ESPINO, GUÁR. / 29.2.50 / RACENIS L. [beige label handwritten in pencil]’ ‘R: 42 [beige label, typed black ink]’ ‘Coll. / G.Ochs [white label, typed black ink] ‘Para- / typoid / SMC C 9258 [red label, black border, typed black ink]’ ‘Senckenberg- /

Museum / Frankfurt / Main [white label, typed black ink]’ ‘ racenisi Ochs   [beige label, handwritten, blue ink, handwriting Ochs’]’ ( SMF).

Other material examined. VENEZUELA: ANZOÁTEGUI: ‘ Transect #1’, 9°16’00.1”N, 64°13’42.9”W, 256 m, 15.viii.2009, leg. R.Cordero, temporary pond at a crossroad, VZ09-0815-11 A, SEMC0909798 View Materials SEMC0909808 View Materials GoogleMaps   ; SEMC0909811 View Materials SEMC0909813 View Materials GoogleMaps   ; SEMC0909816 View Materials (11 spec. SEMC)   . APURE: San Fernando de Apure , 2.viii.1975, leg. J. K. Bouseman & R. B. Selander, USNM ENT 00717231 View Materials (1 spec. USNM)   . FALCÓN: Sierra San Luis, W Curimagua, Blackwater lagoon, 11°10.342’N, 69°42.730’W, 1330 m, 11.vii.2009, leg. Short et al., VZ09-0711- 01 A, SEMC0862274 View Materials SEMC0862284 View Materials GoogleMaps   ; SEMC0862294 View Materials SEMC0862297 View Materials GoogleMaps   ; SEMC0862299 View Materials , SEMC0862307 View Materials SEMC0862310 View Materials   ; SEMC0862312 View Materials SEMC0862314 View Materials   ; SEMC0862318 View Materials SEMC0862319 View Materials   ; SEMC0862321 View Materials , SEMC0862323 View Materials SEMC0862324 View Materials   ; SEMC0862327 View Materials SEMC0862328 View Materials   ; SEMC0862330 View Materials SEMC0862332 View Materials   ; SEMC0862334 View Materials SEMC0862342 View Materials   ; SEMC0862345 View Materials SEMC0862347 View Materials   ; SEMC0862351 View Materials SEMC0862354 View Materials   ; SEMC0862358 View Materials , SEMC0862360 View Materials SEMC0862366 View Materials   ; SEMC0862368 View Materials , SEMC0862370 View Materials SEMC0862373 View Materials   ; SEMC0862375 View Materials SEMC0862376 View Materials   ; SEMC0862556 View Materials SEMC0862558 View Materials   ; SEMC082562 View Materials   ; SEMC0862568 View Materials SEMC0862574 View Materials   ; SEMC0862576 View Materials SEMC0862580 View Materials   ; SEMC0862582 View Materials SEMC0862583 View Materials   ; SEMC0862585 View Materials SEMC0862591 View Materials   ; SEMC0862594 View Materials SEMC0862597 View Materials   ; SEMC0862599 View Materials , SEMC0862600 View Materials , SEMC0862603 View Materials , SEMC0862606 View Materials , SEMC0862610 View Materials SEMC0862613 View Materials   ; SEMC0862616 View Materials SEMC0862617 View Materials   ; SEMC0862619 View Materials SEMC08621 View Materials   ; SEMC0862625 View Materials - SEMC0862627 View Materials   ; SEMC0862629 View Materials SEMC0862637 View Materials   ; SEMC0862639 View Materials (120 spec. SEMC)   ; Medanos de Coro , 11°26.215’N, 69°40.112’W, 8 m, 9.vii.2009, leg. Short et al., large pond in dunes, VZ09-0709-03 A, SEMC0862641 View Materials SEMC0862649 View Materials GoogleMaps   ; SEMC0862651 View Materials SEMC0862652 View Materials , SEMC0862654 View Materials SEMC0862655 View Materials   ; SEMC0862657 View Materials SEMC0862665 View Materials   ; SEMC0862786 View Materials SEMC0862788 View Materials   ; SEMC0862792 View Materials   ; SEMC0862794 View Materials SEMC0862799 View Materials   ; SEMC0862801 View Materials   ; SEMC0862833 View Materials SEMC0862838 View Materials   ; SEMC0862840 View Materials –SEMCSEMC0862858   ; SEMC0862860 View Materials SEMC0862871 View Materials   ; SEMC0862804 View Materials , SEMC0862808 View Materials SEMC0862816 View Materials   ; SEMC0862818 View Materials SEMC0862821 View Materials   ; SEMC0876793 View Materials   ; SEMC0876816 View Materials   ; SEMC0876846 View Materials   ; SEMC0877874 View Materials   ; SEMC0880612 View Materials SEMC0880613 View Materials   ; SEMC0880653 View Materials SEMC0880655 View Materials   ; SEMC0880666 View Materials . (95 spec. SEMC, MIZA, MALUZ)   ; SE Tocopero , 11°26.922’N, 69°13.109’W, 12 m, 10.vii.2009, leg. Short et al., margin of large open pond, VZ09-0710-03 A, SEMC0862505 View Materials SEMC0862506 View Materials GoogleMaps   ; SEMC0862508 View Materials SEMC0862511 View Materials GoogleMaps   ; SEMC0862513 View Materials SEMC0862514 View Materials   ; SEMC0862516 View Materials   ; SEMC0862520 View Materials   ; SEMC0862522 View Materials SEMC0862523 View Materials   ; SEMC0862525 View Materials SEMC0862526 View Materials   ; SEMC0862528 View Materials SEMC0862529 View Materials   ; SEMC0862532 View Materials SEMC0862533 View Materials   ; SEMC0862538 View Materials SEMC0862539 View Materials (20 spec. SEMC)   . GUÁRICO: 20 km S Calabozo, collected in Rio Orituco , 8–13.ii.1969, leg. P. & P. Spangler, USNM ENT 00717229 View Materials (1 spec. USNM)   ; 44 km S Calabozo, Hato Masaguaral , 5.iii.1986, leg. P. J. Spangler, colln#25, USNM ENT 00717232 View Materials (1 spec. USNM)   ; Camaguan , 12.ii.1969, leg. P. & P. Spangler, USNM ENT 00717230 View Materials (1 spec. USNM)   ; pond W Las Mercedes Rivs. , 9°5.067’N, 66°28.500’W, 8.i.2009, leg. Short & Miller, VZ 09010804 (1 spec. KBMC) GoogleMaps   ; nr. Socorro , 8°59’1.9”N, 65°44’18.8”W, 110 m, 29.vii.2008, leg. A. Short & M. García, muddy ditch, AS-08-050, SM0827656 (1 spec. SEMC). Non-Venezuelan material examined GoogleMaps   . BRAZIL: RIO DE JANERIO: Itatiaia , 17.iv.1960, leg. Borvs Malkin, temporary ‘middy’ puddle (27 spec. FSCA)   .

Diagnosis. Body form ( Fig. 3) broadly oval, strongly convex in lateral view; pronotal and elytral margins broad, often yellow in color; elytral disc with non-uniform reticulation, medially appearing polished, laterally bronzy-metallic in appearance; striae V–XI ( Fig. 7) evident with distinctpunctures ( Fig. 21), striae VI–IXsulcate ( Fig. 7); elytral intervals VII–IX convex; elytral apex obliquely truncate ( Fig. 8), border incomplete, epipleural angle distinct, often with denticle ( Fig. 9); metanepisternal ostiole absent; aedeagus ( Fig. 29) with median lobe shorter than parameres, narrow, with leaf-like apical process; gonocoxae ( Fig. 53) short, with strongly truncate apices.

Gyrinus ovatus   is most similar to G. gibbus   , but can be distinguished from G. gibbus   by having more evident elytral striae ( Fig. 7, V–XI strongly evident), with VI–IX sulcate, and elytral intervals VIII–X distinctly convex, while in G. gibbus   fewer elytral striae are evident ( Fig. 10, only VI–XI), and the elytra are evenly convex and normally none-sulcate, with only striae VIII–IX being at times weakly sulcate. The two species can further be distinguished by their elytral apices: in G. ovatus   the elytral apices are obliquely truncate ( Fig. 8) with a distinct epipleural angle often bearing a denticle ( Fig. 9), while in G. gibbus   the elytral apices are most often rounded ( Fig. 11), infrequently subtruncate, and never with adistinct epipleural angle. Although less reliably, G. ovatus   frequently has yellow lateral margins of the elytraand pronotum, compared to G. gibbus   which often has these similarly colored as the remainder of the elytra and pronotum, and only infrequently has yellow lateral margins of the elytra only. The aedeagus is quite different between the two species (cf. Figs 12–17 and 29) and is the most reliable way to separate them. The gonocoxae also easily separate the two species, as G. ovatus   has much shorter and more quadrate gonocoxae ( Fig. 53) compared to the more elongate gonocoxae ( Figs 51–52) of G. gibbus   .

Redescription. Size. Length = 3.5–5.5 mm, width = 2.5–3.0 mm. Habitus. Body form broadly oval, attenuatedanteriorly and very weakly soposteriorly, widest point at elytral midlength; in lateral view strongly dorsoventrally convex, greatest convexity posterior to scutellar region, weakly depressed anteriorly, strongly depressed posteriorly.

Coloration ( Fig. 3). Dorsally, head, pronotum, elytra bronzy-green, lateral margins of pronotum and elytral often yellow, some specimens reddish, others similarly colored as remainder of pronotum and elytra; ventrally lightly colored, mouthparts, ventral surface of pedicel, hypomeron, elytral epipleuron, light yellow, remainder of venter slightly darker yellow to orangish-yellow in color.

Sculpture and structure. Pronotum with broad lateral margins. Elytra ( Fig. 7) with striae I–IV weakly present, evident as reticulate stripes with variously developed sparse, weakly impressed punctures; V–XI strongly evident, composed of distinct punctures; VI–IX sulcate with distinct punctures ( Fig. 21) evident inshallow depression; stria X non-sulcate, punctures widely separate; stria XI marginal, weakly elevated briefly in basal 1/3. Elytral intervals I–III ( Fig. 20) with reticulation composed of meshes with small sculpticells, producing a polished appearance; intervals IV–VI with reticulation more strongly impressed basally, meshes composed of larger sculpticells producing a metallic appearance; intervals VII–XI ( Fig. 21) entirely with more strongly impressed metallic reticulation; intervals VIII–X distinctly convex. Elytra without pre-apical medial plica; apices obliquely truncate ( Fig. 8); border incomplete, present laterally, effaced medially; epipleural angle prominent, often with small denticle ( Fig. 9). Metanepisternal ostiole absent. Ultimate abdominal tergite without strong medial acumination.

Male genitalia ( Fig. 29). Aedeagus with median lobe just shorter than parameres, gradually narrowing apically, abruptly laterally expanded in apical 1/4 forming a leaf-like process, apex rounded, weakly bifid medially; parameres with apex obliquely truncate, often weakly marginated. Female genitalia ( Fig. 53). Gonocoxae short, quadrate with truncate apices.

Variability. This species is most variable in the development of the punctures of the elytral striae. In some populations examined the punctures of elytral stria IV were regularly evident, and even those of striae II and III apically in some specimens. The size of the punctures of striae VII–IX also varied considerably with many specimens from Venezuela having large coarse punctures, while the additional specimens examined from Brazil had very small and widely spaced punctures.

How stronglysulcatethe lateralstriae appeared varied among populations, butall specimens had at least striae VII–IX sulcate. Specimens from near Tocopero in Falcón had only elytral striae VII–IX sulcate, and very weakly so. Those from Medanos de Coro in the same state similarly hadonly striae VII–IX evidently sulcate, but considerablymore strongly sulcate than those from Tocopero. Specimens from Guárico had the most strongly sulcate elytra among the Venezuelan populations studied, with striae VI also appearing weakly sulcate, similar to the additional material examined from Itatiaia, São Paulo, Brazil.

The shape of the elytral apices also varied noticeably. Most populations have the elytral apices obliquely truncate with the epipleural angle possessing a denticle. However, some specimens had somewhat more rounded elytral apices, with the epipleural angle distinct, but without a noticeable denticle. The development of the border of the elytral apex also varied, but was never fully present in a manner truly comparable to G. gibbus   .

Habitat. In Venezuela, this species has been collected in a variety of lentic habitats, including ponds, ditches, and marshes (Figs 64–67).

Distribution. This is a very widely distributed Neotropical specieswith a similar distribution to G. gibbus   , found from Argentina to Mexico ( OCHS 1948, 1949). Within Venezuela, this species has been found in the Llanos and along the northwest coast ( Fig. 74).

Discussion. OCHS (1953) described G. racenisi   ( Fig. 78) from specimens collected in the central Venezuelan state of Guárico, considering them distinct from G. ovatus   by having more strongly impressed lateral striae with more convex associated elytral intervals, and a reddish color to the lateral margin of the pronotum and elytra. These differences represent intraspecific variation in elytral features, as how sulcate the lateral striae are (affecting both impression and convexity of nearby intervals) is one of the most common ways this species varies (see above discussion of variability). The lateral margins of the pronotum andelytra of all species of Neogyrinus species   commonly vary considerably in their color (see structures of taxonomic importance). Furthermore, dissection of male specimensfrom Guáricowith this variation reveals identical genitalia to G. ovatus   . While thetype material of G. ovatus   appears lost (H. Fery pers. comm.), the identity of G. ovatus   has remained clear givenits unique elytral apices (figured as early as RÉGIMBART 1884: Pl. 6, Fig. 93) and its very distinctive median lobe (first described by OCHS 1935a). Given this, and the few variable, external characters used to erect G. racenisi   we here synonymize it with G. ovatus   .

SMF

Forschungsinstitut und Natur-Museum Senckenberg

SEMC

University of Kansas - Biodiversity Institute

USNM

Smithsonian Institution, National Museum of Natural History

MIZA

Museo del Instituto de Zoologia Agricola Francisco Fernandez Yepez

FSCA

Florida State Collection of Arthropods, The Museum of Entomology

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Gyrinidae

Genus

Gyrinus

Loc

Gyrinus (Neogyrinus) ovatus Aubé, 1838

Gustafson, Grey T. & Short, Andrew E. Z. 2017
2017
Loc

Gyrinus ovatus Aubé, 1838: 708

OCHS G. 1953: 188
OCHS G. 1935: 126
AUBE C. 1838: 708
1838