Cyclosomus flexuosus (Fabricius)

Kavanaugh, David H. & Cueva-Dabkoski, Mollie, 2023, A Review of Genus Cyclosomus Latreille (Coleoptera: Carabidae: Lebiinae: Cyclosomini) in Asia., Proceedings of the California Academy of Sciences 67 (21), pp. 493-537 : 503-507

publication ID

https://doi.org/ 10.5281/zenodo.11512952

persistent identifier

https://treatment.plazi.org/id/1C1187FC-EB62-ED4B-FF9E-FC0C62DC82CC

treatment provided by

Felipe

scientific name

Cyclosomus flexuosus (Fabricius)
status

 

Cyclosomus flexuosus (Fabricius) View in CoL

Figures 5 View FIGURE , 6 View FIGURE , 14B View FIGURE , 15B View FIGURE , 16B View FIGURE , 17B View FIGURE , 20 View FIGURE Carabus flexuosus Fabricius, 1775:246 . LECTOTYPE, here designated, a male, deposited in ZMUK, labeled:

Scolytus flexuosus “ [handwritten]/ “ LECTOTYPE Carabus flexuosus Fabricius 1775 View in CoL design. by D.H.

Kavanaugh & M. Cueva-Dabkoski 2022” [red label]. Type locality: eastern India. Scolytus flexuosus (Fabricius) , Fabricius (1790:221; 1792:180). Cyclosomus flexuosus (Fabricius) View in CoL , Andrewes (1921:153 and 166, 1924a:464, 1927:105, 1930:365); Heller

(1923:302); Csiki (1932:1295); Lorenz (2005:452); Kavanaugh (2015). Cyclosomus dytiscoides Nietner, 1857:312 . LECTOTYPE, here designated, a female, deposited in MFNB,

labeled: “ Ceylon, Nietner ” [handwritten]/ “ Type ” [red label]/ “ SYNTYPUS Cyclosomus dytiscoides

Nietner 1857 ” [red label]/ “ LECTOTYPE Cyclosomus dytiscoides Nietner 1857 design. by D.H.

Kavanaugh & M. Cueva-Dabkoski 2023” [red label]. Paralectotypes examined: one female, also in

MFNB, labeled: “ Cyclosomus dytiscoides Nietner ” [handwritten]/ “Type” [red label]/ “ SYNTYPUS

Cyclosomus dytiscoides Nietner 1857 View in CoL labeled by MNHUB 2013” [red label]/ “ PARALECTOTYPE

Cyclosomus dytiscoides Nietner 1857 View in CoL design. by D.H. Kavanaugh & M. Cueva-Dabkoski 2023” [yellow

label]. Type locality: Sri Lanka, Western Province, Negombo. Chaudoir (1876:31); Bouchard

(1903:174); Andrewes (1921:154, 1927:105); Csiki (1932:1295); Kavanaugh (2015:281). Synonymy

proposed by Andrewes (1921:154)

Notes on types and nomenclature. We follow Andrewes (1921:31) in recognizing the Fabrician specimen at ZMUK as the type of C. flexuosus and provide lectotype designations for both C. flexuosus and C. dytiscoides to promote nomenclatural stability.

Diagnosis. Adults of C. flexuosus can be distinguished from those of other Cyclosomus species in Asia by the following combination of character states: Body size larger for genus, BL males = 8.2 to 9.4 mm, females = 8.3 to 9.8 mm; body form ( Figs. 5A, 5C View FIGURE , 6A, 6B View FIGURE ) slightly elongate ovoid; pronotum ( Fig. 14B View FIGURE ) relatively broader (ratio PWM/PL = 2.45 to 2.69), disc light reddish brown to rufopiceous, with lateral pale bands moderately broad but not sharply defined, anterior angles broad and broadly rounded apically, lateral margins smoothly arcuate, not sinuate near anterior angles; elytra with pattern of dark maculae more extensively developed than average in most specimens ( Figs. 5C View FIGURE , 6A View FIGURE ) but highly varied and less than average ( Figs. 5A View FIGURE , 6B View FIGURE ) in a few specimens, preapical dark spot present; elytral epipleuron with long setae over entire length (although many of these are broken off in many specimens); male median lobe with apical lamella slightly recurved dorsally in relation to ventral curvature of shaft in lateral aspect ( Fig. 16B View FIGURE ), apical lamella broadly triangular with a distinct, more narrowly-rounded projection apicomedially in dorsal aspect ( Fig. 17B View FIGURE ).

In describing C. flexuosus, Kavanaugh (2015) incorrectly stated “Male with middle tarsomeres 1 to 3 not laterally expanded and without ventral pads of adhesive setae.” In fact, C. flexuosus males, like those of all the other Cyclosomus species represented in Asia for which males are known, have middle tarsomeres 1 to 3 distinctly expanded in comparison with those in females and have two longitudinal rows of squamatous adhesive setae ventrally on tarsomeres 1 to 3. In contrast, most (four of six) species in the Afrotropical Region have the male middle tarsi similar to those of females in form (i.e., more slender) and in the absence of ventral adhesive setae.

This species demonstrates the greatest range of variation in elytral dark color pattern seen among all species in the Asian fauna. The extremes are represented in Fig. 6 View FIGURE , with the most broadly developed dark pattern ( Fig. 6A View FIGURE ) covering more than 50% of the elytral surface, and the least developed pattern ( Fig. 6B View FIGURE ) restricted to the basal dark band, a typical longitudinal dark band, a relatively narrow middle dark band extended only to interval 4, and a small preapical spot. The patterns seen in the type specimens of C. flexuosus ( Fig. 5A View FIGURE ) and its junior synonym, C. dytiscoides ( Fig. 5B View FIGURE ), are close to the opposite extremes for the species, so it is certainly understandable that they would have been described as distinct species on the basis of different color patterns.

Members of this species share epipleura having relatively long setae throughout their length only with those of C. philippinus ; but they differ from the latter in having a prepical pale spot present and pronota with the pale lateral bands less well-defined medially. Males of the two species differ markedly in the curvature of the male median lobe in lateral aspect (compare Fig. 16B View FIGURE with Fig. 16E View FIGURE ) and shape of the apical lamella in dorsal aspect (compare Fig. 17B View FIGURE with Fig. 17E View FIGURE ). The elytra color pattern of darker specimens of C. flexuosus is most similar to that seen in C. sumatrensis ( Fig. 11 View FIGURE ) and some C. suturalis ( Fig. 12C View FIGURE ) specimens; but members of both of these species have long epipleural setae only on the humeral and subhumeral regions and progressively and distinctly shorter setae to toward the apex. Also, males of these species have the male median lobe less curved in lateral aspect ( Figs. 16F, G View FIGURE ) and the apical lamella of distinctly different shape (compare Fig. 17B View FIGURE with Figs. 17F and 17G View FIGURE ).

Habitat distribution. Not yet reported, but presumed to be restricted to sandy substrates in the vicinity of streams or other water bodies and any associated dune systems, and likely also to occur in such sandy areas along ocean shores. Several localities from coastal areas both on the Indian Subcontinent and in Sri Lanka likely represent occurrences in coastal sand beach or dune habitats. The apparent elevational range of this species extends from at or near sea level (3 m on Mannar Island, Sri Lanka) to at least 500 m (near Kurseong in West Bengal, northern India).

Geographical distribution. We have examined a total of 176 specimens (90 males and 86 females) from the following localities: BANGLADESH / INDIA: “Bengala” ([one female; MFNB]). INDIA ([two males and one female; IRSNB]) : Arunachal Pradesh: Bhalukpong (27.0333°/92.5833°, 150 m, 26 May-3 June 2006, P. Pacholátko collector [two females; NHMUK]) ; Gujarat: Kinara ([one female; NHMUK]) ; Karnataka: Belagavi ([one female; NHMUK]) ; Shivamogga ([one male; NHMUK]) ; Kerala: Malabar ([16 males and 17 females; IRSNB], [two females; NHMUK]) ; Madhya Pradesh: Barwai ([one males and three females; IRSNB]) ; Odisha: Brahmapur ([one female; NHMUK]) ; Puducherry: Karaikal ( Karaikal , July 1962, P.S. Nathan collector [eight male and four females; EMEC], August 1955 [one male; NMNH]) , July 1956 [16 males and seven females; CAS] , [one male and two females; MFNB]), ( Nedungadu , June 1931 [one female; NHMUK], 10 May 1932 [one male and one female; NHMUK]) , Mahé ( Malabar Coast , July 1951, M. Maindron collector [12 males and three females; IRSNB]) ; Tamil Nadu: Anaimalai Hills ( Cinkona , 1070 m, May 1966, P.S. Nathan collector [five males and ten females; MFNB]) , Chennai ([one male and one female; NHMUK]) , Coimbatore (October 1958 [three males and two females]; NHMUK]) , Ramanathapuram ([one male; IRSNB]) , Tiruchirappalli (1905, P. du Breuil collector [one male and four females; IRSNB] , R.P. Castets collector [one male and two females; IRSNB],([two males and two females; IRSNB], [one female; MFNB]) ; Uttarakhand: Kumaon Division ( West Almora , November 1918, H.G. Champion collector [two females; NHMUK]) ; West Bengal: Kurseong (1904 [three males and one female; IRSNB]) ; “ Ind. Or. ” ([one female; MFNB]) ; “ Inde Meridionale ” ([one female; IRSNB]) ; “ South India ” ([one female; NHMUK]) . NEPAL ([one female; NHMUK]) : Bagmati Province: Chisapani Garhi District ( Hetauda , 540 m, 26 September 1960, H. Brydon collector [one male and one female; CAS]) ; Lumbini Province: Bardiya National Park ( Babi River , 200 m, 28 June 2000, T.W. Harman collector [one female; NHMUK]) . SRI LANKA ([one female; MFNB]), ([two males and one female; NHMUK]) : Sabaragamuva Province: Kitulgala (Kitulgala Rest House, 150 m, 24-26 October 1977, K.V. Krombein, T. Wijesinhe, M. Jayaweera, and P. A. Panawatta collectors [one male; NMNH]), Uggalkaltota (150 m, 10-14 October 1970, O.S. Flint, Jr. collector [two males; NMNH]) ; North Central Province: Polonnaruwa (4 May 19080, W.N. Mathis, T. Wijesinhe, and L. Jayawickrema collectors [one female; NMNH]) ; Northern Province: Kondachchi ( Ma Villu , 11-12 April 1981, K.V. Krombein, L. Weeratunga, and P. Leanage collectors [one female; NMNH] , Mannar Island (3.2 km W of Pesalai, 3 m, 24 March 1970, Davis and Rowe collectors [six males and one female; NMNH]) ; Western Province: Colombo ([one female; NHMUK]) , Negombo ([two females; MFNB]) . Specimens without or with illegible locality data: (5 July 1909 [one male; NHMUK]) ([one male; NHMUK]) .

The known geographical range of C. flexuosus ( Fig. 20 View FIGURE ) covers most of the Indian Subcontinent, from the southern base of the Himalayan Mountains in the north to Sri Lanka in the south. We have examined specimens from Arunachal Pradesh, Gujarat, Karnataka, Kerala, Madhya Pradesh, Odisha, Puducherry, Tamil Nadu, Uttarakhand, and West Bengal states in India, as well as Nepal, and Sri Lanka. Kavanaugh (2015) reported on a disjunct record of this species from “Nubia” (historical name for the area including southern Egypt and northern Sudan centered on the Nile River valley ) and commented on that occurrence .

Geographical variation. Although there is evident individual variation ( Figs. 5A, 5C View FIGURE , 6 View FIGURE ) in development of the dark color pattern of the elytra throughout the range of this species, we could not discern any particular geographic component to that variation.

Geographical relationships with other Cyclosomus species. This species has been found synotopic only with C. acutangulus (in Arunachal Pradesh, India) at the northwesternmost known locality for the latter species. The range of C. flexuosus overlaps that of C. vespertilio sp. nov. in northern India and Nepal, but these two species have not yet been found together. Known localities for C. flexuosus in northern West Bengal and C. suturalis in southernmost Sikkim are less than 30 km apart, so at least some overlap in their ranges is likely. Because of uncertainty with respect to the respective geographical ranges of C. inustis , C, marginatus , and C. suturalis (see discussions below), it is possible but not yet confirmed that one or more of these overlap with C. flexuosus at least in the eastern part of its range.

MFNB

Museo Friulano di Storia Naturale

IRSNB

Institut Royal des Sciences Naturelles de Belgique

NHMUK

Natural History Museum, London

EMEC

Essig Museum of Entomology

NMNH

Smithsonian Institution, National Museum of Natural History

CAS

California Academy of Sciences

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Carabidae

Genus

Cyclosomus

Loc

Cyclosomus flexuosus (Fabricius)

Kavanaugh, David H. & Cueva-Dabkoski, Mollie 2023
2023
Loc

Cyclosomus dytiscoides

Nietner 1857
1857
Loc

Cyclosomus dytiscoides

Nietner 1857
1857
Loc

Carabus flexuosus

Fabricius 1775
1775
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