Sandracottus dejeanii ( Aubé, 1838 )

Hendrich, Lars & Brancucci, Michel, 2025, Revision of the Oriental and Australasian diving beetle genus Sandracottus Sharp, 1882 (Coleoptera, Dytiscidae, Dytiscinae), ZooKeys 1223, pp. 87-147 : 87-147

Sandracottus dejeanii ( Aubé, 1838)

Figs 4 , 15 , 26 , 34 , 35 , 50

Hydaticus dejeanii Aubé, 1838: 165 (type locality “ Indes Orientales ”).

Sandracottus dejeani ( Aubé, 1838) (sic.): Sharp, 1882: 686 (comb. nov.); Régimbart 1899: 335 (descr.); Zimmermann 1920: 234 (cat.); Guéorguiev 1965: 111 (faun.); Vazirani 1969: 275 (descr., cat.); Vazirani 1971: 25 (cat.); Sonali et al. 2022: 339 (faun.).

Sandracottus dejeanii ( Aubé, 1838): Hájek 2006: 50 (faun.); Ghosh and Nilsson 2012: 18 (cat.); Ghosh 2015 a: 81 (faun.); Ghosh 2015 b: 77 (faun.); Shangar et al. 2023: 455 (faun.); Deb and Subramanian 2023: 14 (faun.); Hájek and Nilsson 2024: 91 (cat.); Shaverdo et al. 2024: 38 (check list, faun.); Sheth et al. 2024: 10, 20 (check list, faun., key).

Sandracottus vijayakumari Anand et al., 2021: 17999–18003 (type locality Western Ghats, Kerala, India) (syn. nov.).

Type material of Hydaticus dejeanii .

Not found ( MNHN).

Type material of Sandracottus vijayakumari .

Not examined.

Additional material.

(143 specimens): • India: 2 exs., “ Mahableshnar W. Ghato, 5500 ft India ”, “ Coll´n J. D. Sherman Jr. 1926 ” ( USNM); 2 exs., “ Aug. 43 Dehra Dun ” [Prov. Uttarakand, 1943, Dehradun, Central Internment Camp for British India near Premnagar, 30 ° 20 N 78 ° 3 E] ( ZSM); 1 exs., “ Okt. 43 Dehra Dun ” ( ZSM); 1 ex., “ Inde méridionale M. Moingeon ” ( NMB); 4 exs., “ India, Batate, Patnitop 1600–2100 m 6. - 8. 8. 1980 W. Heinz leg. ” ( NMB); 1 ex., “ India Hydarabad M. Halva leg. ” ( NMB); 2 exs., “ Chota Nagpore Nowatoli R. P. Cardon VII-IX. 1888 ” ( NMB, MNHN); 2 exs., “ Puna ”, “ Coll. Kraatz ”, “ Zimmermann det. ” ( DEI); 23 exs., “ Inde Anglaise, Kalka, ex. Coll. Oberthür ” ( MNHN); 32 exs., “ Chota-Nagpore Nowatoli R. P. Cardon VIII-IX. 1896 ” ( MNHN); 4 exs., “ Chota Nagpore, Nowafoli, R. P. Cardon, VIII-IX 1898 ” ( RMNH); 4 exs., “ Chota-Nagpore Nowatoli, R. P. Cardon IX-X. 1896 ” ( MNHN); 1 ex., “ Chota-Nagpore Nowatoli R. P. Cardon IV-V. 1897 ” ( MNHN); 5 exs., “ Maissour Shinoga Mai 1897 ” ( MNHN); 3 exs., “ Val de Kangra [Himachal Pradesh] Dharamsala vers 1300 m, J. Berlioz, 1937 ” ( NMB, MNHN); 1 ex., “ Calcutta [Kolgata] Ex. Museo E. Steinheil ” ( MNHN); 1 ex., “ Ex. E. Wehncke Acqu. 1884 ” ( MNHN); 1 ex., “ India bor. 980 Dejeani, Sharp Coll. 1905-313 ” ( NHMUK); 1 ex., “ Western Ghats, Bombay [Mumbay], 2250 feet, Matheran, Charlotte Lake, 31. III. 1908 & pres. 1908 by G. B. Longstaff ” ( NHMUK); 1 ex., “ S. Bombay 1902.294. ” ( NHMUK); 1 ex., “ Matheran II. 1919 P. H. ”, “ Brit. Mus. 1978-16 ” ( NHMUK); 3 exs., “ India N. W. frontier, E. Y. Watson 98-142 ” ( NHMUK); 1 ex., “ India orient ”, “ Fry Coll. 1905-100 ( NHMUK); 1 ex., “ India 980 Dejeani ”, “ Sharp Coll. 1905-313 ” ( NHMUK); 3 exs., “ Khandesh, T. R. Bell, H. E. Andrewes Bequest. ”, “ B. M. 1922-221 ” ( NHMUK); 6 exs., “ Khandesh, H. E. Andrewes Bequest. B. M. 1922-221 ” ( NHMUK); 3 exs., “ Belgaum, H. E. Andrewes Bequest. B. M. 1922-221 ” ( NHMUK); 1 ex., “ India ” ( NHMUK); 2 exs., “ Nilghiri Hills, H. L. Andrewes ” ( NHMUK); 1 ex., “ Achmednagar, Gebauer leg. ” ( NMW); 2 exs., “ Shimoga, Et. Myore, V. 1936 ” ( MNHN); 6 exs., “ South India, Salem District, IX. 1943, P. S. Nathan leg. ” ( MNHN); 1 ex., “ India ” ( MNHN); 2 exs., “ India Sunderbunds ” ( MNHN); 6 exs., “ India, Sundabunds ” ( MNHN); 1 ex., “ India, Sundabunds ”, “ coll. Gärtner ” ( DEI); 1 ex., “ S-India, Salem Distr. IX. 1934 Nathan leg. ” ( NMB); 1 ex., “ Orissa, Daitari, 31. XII. 1966, collected on lamp, Gy Topal leg. ” ( NMB); 4 exs., “ Orissa, Jaipur Keonjahr, District Daitari, 29. XI. 1967, netted from water, Gy Topal leg. ” ( NMB); 1 ex., “ Dehra Dun 1883 Dr. Warth leg. ” ( CGW); 1 ex., “ Madhya Pradesh, Jablpur Dagmaga, 18. IV. 1968, V. S. Durve leg. ” ( CGW); 1 ex., “ Ostindien “, “ Samml. A. Zimmermann ” ( ZSM); 1 ex., “ Madras, “ Samml. A. Zimmermann ” ( ZSM); 2 exs., “ India or., Behar, “ Samml. A. Zimmermann ” ( ZSM); 2 exs., “ Khandesh., 27. II. 1902, in water, T. R. Bell ”, “ Samml. A Zimmermann ” ( ZSM); 2 exs., “ Coorg Hallery, Fletcher leg. ”, “ Samml. A. Zimmermann ” ( ZSM); 1 ex., “ India, Bombay Biro. 902 ” ( TDMB); 2 exs., “ India, Orissa, Jajpur-Keonjahr, District Daitari, leg. Gy Topál, No. 975, netted from water, 29. XI. 1967 ” ( TDMB); 1 ex., “ India or. ” ( TDMB); 1 ex., “ India, Madras ” ( TDMB); 2 exs., “ Maharashtra, Igatpuri env. 120 km NE Mumbai, 600 m, 1. - 12. VIII. 2002, 19 ° 42.17 ' N, 73 ° 33.06 ' E, P. Šípek & M. Fikáček leg. ” ( NMPC); 1 ex., “ Tamil Nadu, 15 km SE Kotagiri, Nilgiris, Kunchappanai, 900 m, 7. - 22. V. 2000, 11 ° 22 ' N, 76 ° 56 ' E, Rolčík leg. ” ( NMPC); 1 ex., “ India S, Tamil Nadu, Nilgiris, 15 km SE of Kotagiri, Kunchappanai, 900 m, 11 ° 22 ’ N 76 ° 56 ’ E, 7. – 22. V. 2000, D. Hauck leg. ” ( CJS); 2 exs., “ Bhimtal 20. V. 1300–1500 m ”, “ India U. P. 8.81 M. Brancucci ” ( NMB); 1 ex., “ Southern Madhya Pradesh Dhobighat Nala [stream] (= Clematis Point Stream), Pachmarhi Wildlife Sanctuary, Satpura Mountain Range, ca 5 km SSE Panchmarhi, Hoshangabad District, 900 m a. s. l., 22 ° 27 ' 31 " N / 78 ° 26 ' 41 " E, 27. II. 2008, M. Jäch leg. (Loc. MP 7) ” ( NMW); 1 ex., “ N 27 ° 08 ' 22 ’’ E 76 ° 20 ' 38 ’’, India bor. Occ., Rajasthan state, Alwar di., Naranimata env., 460 m, 20–30.7. 2002, lgt. P. Šrámek ” ( NMPC). • Iran: 1 ex., “ Sistan va Baluchestan Prov., Bampur, 6. - 16. VI. 1997, M. Kafka leg. ” ( NMPC); 1 ex., “ Sistan va Baluchestan Prov., Pir Sohrab env., 100 m, pool in dried up Wadi, 11. - 12. IV. 2000, 25 ° 44 ' N 60 ° 50 ' E, J. Hájek & M. Mikát leg. ” ( NMPC). • Myanmar: 1 ex., “ Mulmein [= Mawlamyaing], 1871, Fieber ” ( NMW). • Nepal: 1 ex., “ Nepal ” ( NHMUK). • Pakistan: 1 ex., “ Pakistan 20. 05. 1998 Kashmir Himalaya Mts. 20 km S Muzaffarabad 73 ° 29 ' E, 34 ° 01 ' N, Nara village Ronkay ” ( CHF); 1 ex., “ Kawai, Khagan Valley 1450–1800 m, 15. 6. 1977, Wittmer & Brancucci ” ( NMB); 1 ex., ” NW Pakistan, Swat Prov., Madyan, 1400 m, VII. 1971, Holzschuh leg. ” ( CGW); 1 ex., ” West Pakistan, Rawalpindi surr., 18. X. 1971, E. Heiss leg. ” ( CGW); 1 ex., “ West Pakistan, Rawalpindi surr., Basal, 16. - 18. I. 1956, Kala Chitta Range, C. Lindemann leg. ” ( ZSM); 1 ex., “ Pakistan, Northern Frontier Province, Tathabaya, 34 ° 36 ' 48 N, 73 ° 27 ' 01 E, 2300 m, at light, No 4–6, 7. - 9. VII. 1998, G. Csorba & L. Ronkay leg. ” ( TDMB).

Doubtfull record and probably mislabelled.

1 ex., “ Philippines Luzon Ch. Semper ” ( MNHN).

Locality unknown.

4 exs., “ leg. Stolicka 1865 ” ( NMW); 2 exs., “ Megerley ” [= coll. Megerle] ( NMW).

Remarks.

Sandracottus vijayakumari recently described by Anand et al. (2021) from the Western Ghats in Kerala, India is proposed as a junior synonym of S. dejeanii . The illustrated and described dorsal colouration of the head, the pronotum, and the elytra is within the range of variation of S. dejeanii which can have both separated and contiguous testaceous markings on the elytra. Furthermore, all 143 specimens of S. dejeanii examined by the authors, including the ones having largely separated testaceous patches on the elytra, have a fine microreticulation with numerous larger punctures on the head. No information was given in the original publication on any differences in genital structure of both taxa.

Redescription.

Body oval, shiny, testaceous to ferrugineus brown with black markings (Fig. 50 ). Ventral side completely dark brown to black, legs testaceous to ferrugineus brown.

Head testaceous with posterior half broadly black: black band protruding forwards to frons, shiny (Figs 4 , 50 ). Surface sculpture consisting of dense microreticulation and of larger, much sparser punctures, particularly numerous on frons. Clypeal grooves, punctures alongside eyes and a transverse depression beside eyes distinctly impressed, punctures large and coalescent. Antennae testaceous; antennomeres slender, antennomere V 4 × as long as broad.

Pronotum testaceous with a median black marking reaching from posterior to anterior margins (Figs 4 , 50 ); long and broad posteriorly, narrower and shorter anteriorly, and strongly constricted in middle. Surface shagreened with a dense punctation; punctures medium-sized. Anterior and lateral puncture lines with dense and coalescent punctures, becoming sparse towards middle and lacking in the very middle of anterior margin. Posterior puncture line distinctly visible only at sides, superficial medially and transformed in long and very superficial wrinkles.

Elytra black to dark brown with testaceous markings in form of a chessboard, the testaceous markings alternating with the black ones. Epipleura testaceous to ferrugineus brown (Figs 4 , 50 ). Surface very slightly and superficially shagreened and covered with a double punctation, a smaller and denser one as well as a larger and much sparser one. Puncture lines with groups of medium-sized punctures.

Ventral side dark brown. Legs particularly fore and mid legs testaceous, hind legs ferrugineus brown to dark brown. Prosternal process very short and broad, 1, 3 × only longer than broad, flattened and superficially sculptured; posterior border broadly rounded. Whole surface very superficially shagreened and finely punctured. Metatibia with only a few small punctures on outer half. Ventrites II – VI shagreened, densely covered with very small punctures and a few larger sparser ones. Posterior margins rounded, bordered with a short row of coalescent punctures in middle.

Measurements: TL = 12.0–13.0 mm, TL-h = 11.1–12.1 mm, TW = 7.3–7.6 mm.

♂. Protarsomeres I – III strongly enlarged with three larger suckers and numerous smaller ones. Mesotarsomeres I – III with two rows of small suckers. Median lobe of aedeagus, in ventral view, narrow and elongate, slightly tapered towards apex (Fig. 15 a ). Parameres also narrow, same length as median lobe, only slightly tapered at apical part (Fig. 15 b ).

♀. Similar to male. Tarsi not enlarged.

Differential diagnosis.

The combination of size and dorsal colour pattern (Figs 4 , 50 ) separates S. dejeanii from all other species of the genus. Furthermore, the species can be separated from all other species of the genus by the shape of the median lobe and parameres (Fig. 15 a, b ).

Distribution.

India: Andhra Pradesh, Arunachal Pradesh, Rajasthan, Assam, Himachal Pradesh, Jharkhand, Karnataka, Madhya Pradesh, Maharashtra, Orissa, Punjab, and Tamil Nadu ( Ghosh and Nilsson 2012; Deb and Subramanian 2023; Sheth et al. 2024); Nepal, Pakistan, Myanmar, and Iranian Baluchistan ( Hájek 2006; Shaverdo et al. 2024) (Fig. 26 ). Specimens were collected from near sea level to 2300 m.

Habitat.

In India widespread in different ponds, rest pools of intermittent streams and artificial water tanks, often rich in aquatic vegetation. The single specimen in Pachmarhi Wildlife Sanctuary was obtained from a forest stream (ca 1–2 m wide) with rocky bottom (Fig. 35 ). In Kerala, Anand et al. (2021) collected the species in a partly shaded, shallow, ditch-like forest pool which was rich in decaying leaves and twigs; lentic habitat. In Iran it was collected in remnant pools in a wadi, in a semidesert area ( Hájek 2006) (Fig. 34 ). Together with the Indian S. festivus and the two subspecies of the Australian S. bakewelli , this species is not restricted to forested areas as are many other species of the genus, especially in Southeast Asia. Sandracottus dejeanii is capable of flight and was attracted to light. The larvae have been described by Vazirani (1971).

Figures

Figure 26. Distribution of Sandracottus dejeanii in Asia.

Figures 4–7. Habitus of 4 Sandracottus dejeanii (South India) 5 S. festivus (Sri Lanka) 6 S. femoralis (Papua New Guinea, Rigo) 7 S. hunteri (Thailand).

Figures 12–15. Median lobe of aedeagus in ventral view (a), and right paramere in lateral view (b) 12 Sandracottus bakewellii bakewellii 13 S. bizonatus 14 S. chevrolati and 15 S. dejeanii.

Figures 31–36. Habitats of Sandracottus 31 Australia, Northern Territory, 50 km S Adelaide River, creek at Scenic Route (NT 9) and 32 South Queensland, Winfield, Winfield Road, rest pool (QLD 54), habitats of S. bakewellii bakewellii (photos: L. Hendrich) 33 Northern Territory, Ormiston Gorge, habitat of S. bakewellii guttatus (photo: M. Baehr) 34 Pakistan, Sistan va Baluchestan Prov., Pir Sohrab env., rest pool in wadi, habitat of S. dejeanii (photo: J. Hájek) 35 India, southern Madhya Pradesh, Hoshangabad District, Pagara – Pachmarhi road, ca 5 km NNE Panchmarhi, Panar Pani, habitat of S. dejeanii and S. festivus (photo: M. Jäch) 36 Indonesia, Irian Jaya, Nabire, Nabire-Ilaga track, km 62, habitat of S. femoralis (photo: L. Hendrich).

Figures 50–53. Habitus of 50 Sandracottus dejeanii (India, Himachal Pradesh, Kangra Valley, Dharamsala) 51 S. festivus (Sri Lanka, Ratnapura, Sincharaja 52 S. femoralis (Indonesia, West Papua, Kapupaten Paniai, Nabire) 53 S. hunteri (China, Central Sichuan).