Copelatus daemeli Sharp, 1882

Hendrich, Lars, Shaverdo, Helena, Hajek, Jiri & Balke, Michael, 2019, Taxonomic revision of Australian Copelatus Erichson, 1832 (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 889, pp. 81-152 : 81

Copelatus daemeli Sharp, 1882 Figures 3 , 4 , 13 , 21 , 32

Copelatus daemeli Sharp 1882: 593 (original description); Larson 1993: 52 (habitat information); Watts 1978: 126 (description); Watts 1985: 26 (general distribution); Watts 2002: 42 (checklist); Nilsson and Hájek 2019: 62 (catalogue).

Type locality.

"Australia [Queensland] (Cape York)".

Type material.

We were not able to find the type material of C. daemeli , neither in Muséum national d’Histoire naturelle, Paris (MNHN) nor in the NHMUK. Copelatus daemeli is originally a manuscript name of Wehncke. The depository of many of Wehncke’s types is unknown, but those which were found and studied are mostly stored in the MNHN. The identity of the species is quite clear and it cannot be confused with any other Australian (or New Guinean) species, therefore the designation of a neotype is not necessary and simply refers to undoubted identity of the species in the revision of Watts (1978).

Material studied (40 specimens).

Western Australia: 1 ex., "Wyndham-East Kimberley, Mitchell Plateau [-14.6667, 125.7333] 23/9/1982 BV Timms", “25001777” (SAMA); 1 ex., "AUSTRALIA/WA/ Shire of Wyndham-East Kimberley, Gibb River Road, King Edward River Crossing, 280 m, 15.6.1999, Hendrich leg./Coll./Loc. 10/110" (CLH). Northern Territory: 1 ex., "Australia: NT, Finnis River 10 km W Batchelor, 43 m, 20.VIII.2006, 13.01.278S 130.57.217E, L. & E. Hendrich leg. (NT 2)", "DNA M. Balke 2523" [green printed label] (ZSM); 1 ex., "Australia: NT, Litchfield NP, Greenant Creek E Tolmer Falls, 51 m, 21.VIII.2006, 13.12.126S 130.42.173E, L. & E. Hendrich leg. (NT 6)", "DNA M. Balke 1607" [green printed label] (ZSM); 1 ex., "Australia: NT, Kakadu NP, small creek on the road to Gunlom, 101 m, 25.VIII.2006, 13.30.422S 132.26.191E, L. & E. Hendrich leg. (NT 16)", "DNA M. Balke 1603" [green printed label] (ZSM); 6 exs., "Australia, NT, Litchfield NP, Florence Falls, 12°51'15"S, 132°45'16"E, 63 m, at light, 12.V.2006, leg. Berger & Dostal (5/06)" (CGH); 1 ex., "Australia, NT, Darwin, 12°51'24"S, 131°46'48"E, 52 m, at light, leg. Berger & Dostal (2/06)" (CGW); 8 exs., "Australia NT/ Old Stuart Hwy, Scenic Drive, Robin Falls, Creek, 50 m, 7.7.1999, Hendrich leg. Loc. 37/137" (CLH); 1 ex., "Australia NT/Litchfield N.P., Florence Falls Camping Area, 120 m, 4.11.1996 13°06.705'S, 130°47.220'E L. Hendrich leg./Lok. 16" (CLH); 1 male, "Australia, N.T./Kakadu N.P., Gunlom Camp. Area, pool in Monsoonal Forest, ca. 50 m, 3.11.1996, 13°26.082'S, 132°24.929'E L. Hendrich leg./Lok. 15" (NMW); 1 ex., "Australia, N.T./Kakadu N.P., Mary River District, Gunlom Camping Area, 50 m, 3.11.1996, 13°26.082'S, 132°24.929'E L. Hendrich leg./Lok. 15" (CLH); 1 ex., "Australia, Northern Territory, Tiwi Islands (S), Tiwi Cobourg, Melville Island, [-11.41666985, 131.5166626], 4.2.1968, Matthews, E. leg." (ANIC); 1 ex., "NT Darwin [-12.4500, 130.8331] 13/5/1963 CHS Watts", “25-008438” (SAMA); 2 exs., "Australia NT Darwin Holmes Jungle Pk uv lt Dec2/93 S Peck" (ZSM). Queensland: 1 ex., "Australia, QLD, Cape York Peninsula, Lockerbie [-10.8, 142.4667] 31.3.1964, Common, I.F.B. & Upton, M.S. leg." (ANIC); 1 ex., "Australia, Queensland, Iron Range Cape York Pen., 26. May 1971-2. June 1971, B.K. Cantrell" (QM); 1 ex., "QLD, Townsville [-19.2, 146.68], 6-11/2/ 1998, AJ Watts", “25-001789” (SAMA); 3 exs., "QLD, Heathlands, Cook [-11.75, 142.58], at light 16/03/1994 Zborowski, P.", “25-023758-978” (ANIC); 4 exs., "QLD, Heathlands, Cook Pappan Creek [-12.65, 142.01], at light 18/02/1994 Zborowski, P.", “25-023756-974” (ANIC); 2 exs., "QLD Cook Iron Range [-12.73332977, 143.2832947] 11/05/1971 JG Brooks", “25-019347-156” (ANIC); 1 ex., "QLD Burster Creek [-10.93333, 142.3833], open forest, at light, 17/10/1992 Weir, T.A. & Zborowski, P.", “25-019372-244” (ANIC).

Description of male.

Body shape: In dorsal view, narrowly elongate, broadest at midlength of elytra. Body outline with small discontinuity between pronotum and elytra. Head relatively broad; anterior margin of clypeus not bordered. Pronotum broadest in middle, lateral margins moderately curved. Base of elytra as broad as pronotal base; lateral margins of elytra moderately curved ( Fig. 4 ).

Colouration: Body dark brown to black, clypeus and sides of pronotum dark ferruginous; appendages testaceous ( Fig. 4 ).

Dorsal surface sculpture: Whole surface shiny ( Fig. 4 ). Head uniformly microreticulated, reticulation weakly impressed with very small meshes. Densely, weakly and minutely punctate; rows of coarse punctures present around inner margin of eyes and in small depression anterolaterally of eyes. Pronotum with lateral beading very thin and indistinct. Microreticulation similar to that of head. Punctation similar to that of head; row of coarse punctures present along anterior margin, basal margin (except for basomedially), and laterally close to sides. Elytra with microreticulation similar to that of head and pronotum, but less impressed. Serial punctures very indistinct, located in striae 4, 6, 8 and 10. Each elytron with ten discal and one well marked submarginal longitudinal stria, alternate striae shorter apically and with a tendency to be interrupted basally. Striae 3 and 5 reduced to a few short grooves and stria 2 broken up basally. Submarginal stria reaching from middle of elytra almost to apical end of stria 10.

Antennae and legs: Antenna with antennomeres long and slender. Protibia modified, angled near base, slightly broadened anteriorly. Pro- and mesotarsomeres 1-3 distinctly broadened, with adhesive discs on their ventral side; claws simple.

Ventral part: Finely microreticulated, with sparsely distributed, very small punctures. Prosternum obtusely keeled medially. Prosternal process quite strong, convex, narrowly flanged and bluntly pointed. Lateral parts of metaventrite tongue-shaped, very slender. Metacoxal lines deep, close apically, evenly and slightly diverging anteriorly. Metacoxae with short sharp striae and abdominal ventrites 1-3 with larger but weaker longitudinal striae.

Male genitalia: Median lobe consisting of a few sclerites, well separated apically ( Fig. 13A, B, C ). Shape of paramere narrowly triangular, with very dense, strong, long setae along dorsal margin ( Fig. 13D ).

Female.

Similar to male in habitus. Protibia simple, not angled basally and only slightly broadened distally; pro- and mesotarsomeres not broadened, without adhesive setae.

Measurements.

TL = 6.2-6.3 mm; TL-H = 5.5-5.6 mm; MW = 2.9-2.95 mm.

Variability.

A dimorphic species. Despite the fact that all specimens studied are rather uniform in habitus and colouration, they vary in extension and number of their elytral striae. Several specimens of both sexes, collected at the same spot at the same time with the main form (NT, Robin Falls), have 11 fully developed elytral striae. ( Fig. 3 ).

Differential diagnosis.

On the first view C. daemeli (especially the form with 11 elytral striae) resembles C. bakewelli but differs in the lack of short striae on the pronotum, the larger size, and the less developed and often shortened and reduced elytral striae in most of the specimens. Furthermore, both species can easily be separated by the form of the median lobe.

Distribution.

Endemic. The species is distributed from the Kimberley region in Western Australia, over Northern Territory (Melville Island, Kakadu Area and around Darwin) to coastal Queensland (Cape York Peninsula) south to Townsville ( Fig. 21 ). Always rare and collected only in low numbers.

Habitat.

The habitat of C. daemeli is not well-known. The few specimens have been collected mainly in seasonal habitats, preferably in forested areas. Several specimens were obtained from isolated pools of intermittent creeks and streams, and pools adjacent to streams in eucalypt or tropical woodland ( Fig. 32A, B ). In Queensland Larson (1993) found a few specimens in a small, silty drying water hole in the otherwise dry bed of a small intermittent stream. Few specimens were taken from a slow flowing spring-fed stream. The species is also attracted to light.

Figures

Figure 3. Habitus and colouration of Copelatus daemeli, female with 11 fully developed elytral striae. Total length 6.3 mm.

Figure 4. Habitus and colouration of Copelatus daemeli, male with reduced elytral striae. Total length 6.2 mm.

Figure 13. Copelatus daemeli A median lobe in lateral view, right side B median lobe in lateral view, left side C median lobe in ventral view D left paramere in external view. Scale bar: 0.5 mm.

Figure 32. Habitat of Copelatus daemeli A Finnis River, Northern Territory, all beetles were at the edge among rotten leaves and twigs B small puddle filled with leaf litter at the road to Gunlom, Kakadu National Park, Northern Territory. Photographs by L. Hendrich.

Figures 20, 21. Distribution of 20 Copelatus bakewelli 21 C. daemeli.