Exocelina broschii (Balke, 1998)

Shaverdo, Helena, Sagata, Katayo & Balke, Michael, 2016, Description of two new species of the Exocelinabroschii-group from Papua New Guinea, with revision and key to all representatives of this species group (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 577, pp. 125-148 : 128

Taxon classification Animalia Coleoptera Dytiscidae

1. Exocelina broschii (Balke, 1998) Figs 1-3, 8, 9 A–E

Copelatus (Papuadytes) broschii Balke, 1998: 327; Nilsson 2001: 76 (catalogue).

Papuadytes broschii (Balke, 1998): Shaverdo et al. 2005: 270, 271 (notes, illustration).

Papuadytes broschii (Balke, 1998): Nilsson and Fery 2006: 56 (addition to catalogue).

Exocelina broschii (Balke, 1998): Nilsson 2007: 33 (comb. n.).

Exocelina undescribed sp. MB1520: Toussaint et al. 2014: Supplementary figs 1-4, tab. 2.

Type locality.

Papua New Guinea: Madang Province, Finisterre Range, Moro, approximately 5°42'47.6"S; 146°03'40.1"E.

Type material studied.

Holotype: male "Stn. No. 82", "NEW GUINEA: Madang Dist., Finisterre Mts. Moro.C.5550ft. 30.x.-15.xi.1964.", "M.E. Bacchus. B.M. 1965-120", “Holotypus” [red], " Copelatus broschii sp.n. Balke des. 1997" (BMNH). Paratypes: 4 males, 1 female with the same labels as the holotype, except for "Paratypus Copelatus broschii sp.n. Balke des. 1997" (BMNH, NHMW, ZSM).

Additional material.

Madang: 1 male "Stn. No. 82", "NEW GUINEA: Madang Dist., Finisterre Mts. Moro.C.5550ft. 30.x.-15.xi.1964.", "M.E. Bacchus. B.M. 1965-120", "Paratypus Copelatus broschii sp.n. Balke des. 1997" (BMNH) - although this specimen is with the paratype label, it is not included in the type material of the original description in Balke (1998). 17 males, 8 females "Papua New Guinea: Madang, Adalbert Mts., Sewan - Keki, 700m, 4.v.2006, 04.42.215S 145.25.154E, Balke & Manaono (PNG 51)" (NARI, NHMW, ZSM). 7 males "Papua New Guinea: Madang, Adalbert Mts., Keki, 850m, 4.v.2006, nr 04.42.300S 145.25.089E, Balke & Manaono (PNG 52)", one male with an additional green label "DNA M.Balke 1300" (NHMW, ZSM). 34 males, 35 females "Papua New Guinea: Madang, Adalbert Mts., below Keki, 790m, 5.v.2006, 04.42.300S 145.25.089E, Balke & Manaono (PNG 53)" (NARI, NHMW, ZSM). 14 males, 13 females "Papua New Guinea: Madang, Adalbert Mts., creek nr Keki, 790m, 28.xi.2006, 04.42.300S 145.25.089E, Binatang Boys leg. (PNG 53a)" (NHMW, ZSM). 4 males, 5 females "Papua New Guinea: Madang, Keki, Adalbert Mts., 400m, 29.xi.2006, 04.43.058S 145.24.437E, Binatang Boys, (PNG 119)" (NHMW, ZSM). 7 males, 6 females "Papua New Guinea: Madang, Keki-Sewan, Adalbert Mts., 700m, 30.xi.2006, nr 04.41.802S 145.25.460E Binatang Boys (PNG 120)" (NHMW, ZSM). 1 male "Papua New Guinea: Madang, Simbai area, 1800-2400m, 8.iii.2007, 05.12.693S 144.35.521E, Kinibel (PNG 151)" (ZSM). 24 males "Papua New Guinea: Madang, Simbai area, 1200m, 10.iii.2007, 05.13.389S 144.37.285E, Kinibel (PNG 152)" (NARI, NHMW, ZSM). 39 males "Papua New Guinea: Madang, Simbai area, 1200m, 11.iii.2007, 05.13.333S 144.37.611E, Kinibel (PNG 153)" (NARI, NHMW, ZSM). 10 males, 2 females "Papua New Guinea: Madang, Simbai - Mombeen, 1100m, 11.iii.2007, 05.12.876S 144.41.759E, Kinibel (PNG 154)" (NHMW, ZSM). Eastern Highlands: 4 males, 6 females "Papua New Guinea: Eastern Highlands, Bena Bridge, 1400m, 8.xii.2007, 06.10.781S 145.26.034E, Balke & Sagata (PNG 164)" (ZSM). 2 males "Papua New Guinea: Eastern Highlands, Akameku - Brahmin, Bismarck Range, 700m, 24.xi.2006, 05.52.754S 145.23.209E, Balke & Kinibel (PNG 109)", one of them with an additional green label "DNA M.Balke 1520" (ZSM). 1 male, 2 females "Papua New Guinea: Eastern Highlands, Akameku - Brahmin, Bismarck Range, 1200m, 24.xi.2006, nr 05.52.754S 145.23.209E, Balke & Kinibel (PNG 110)", one female with an additional green label "DNA M.Balke 1522" (ZSM). 8 males "Papua New Guinea: Eastern Highlands, Akameku - Brahmin, Bismarck Range, 800m, 24.xi.2006, 05.50.021S 145.24.664E, Balke & Kinibel (PNG 112)" (NHMW, ZSM). 18 males "Papua New Guinea: Eastern Highlands, Akameku - Brahmin, Bismarck Range, 750m, 25.xi.2006, 05.49.892S 145.24.491E, Balke & Kinibel (PNG 113)" (NARI, NHMW, ZSM). 3 males "Papua New Guinea: Madang, Akameku - Brahmin, Bismarck Range, 750m, 25.xi.2006, nr 05.49.307S 145.24.389E, Balke & Kinibel (PNG 114)" (NHMW, ZSM).

Females of doubtful identity. Eastern Highlands: 12 females "Papua New Guinea: Eastern Highlands, Akameku - Brahmin, Bismarck Range, 700m, 24.xi.2006, 05.52.754S 145.23.209E, Balke & Kinibel (PNG 109)" (ZSM). 24 females "Papua New Guinea: Eastern Highlands, Akameku - Brahmin, Bismarck Range, 800m, 24.xi.2006, 05.50.021S 145.24.664E, Balke & Kinibel (PNG 112)" (NARI, NHMW, ZSM). 15 females "Papua New Guinea: Eastern Highlands, Akameku - Brahmin, Bismarck Range, 750m, 25.xi.2006, 05.49.892S 145.24.491E, Balke & Kinibel (PNG 113)" (NHMW, ZSM). 25 females "Papua New Guinea: Madang, Akameku - Brahmin, Bismarck Range, 750m, 25.xi.2006, nr 05.49.307S 145.24.389E, Balke & Kinibel (PNG 114)" (NARI, NHMW, ZSM). These females are a mixture of two species: Exocelina broschii and Exocelina damantiensis (Balke, 1998). 19 males "Papua New Guinea: Madang, Simbai area, 1200m, 10.iii.2007, 05.13.389S 144.37.285E, Kinibel (PNG 152)" (NHMW, ZSM). These females are a mixture of two species: Exocelina broschii and Exocelina? damantiensis (Balke, 1998). 53 females "Papua New Guinea: Madang, Simbai area, 1200m, 11.iii.2007, 05.13.333S 144.37.611E, Kinibel (PNG 153)" (NARI, NHMW, ZSM). These females are a mixture of three species: Exocelina broschii , Exocelina simbaiarea Shaverdo & Balke, 2014, and Exocelina? damantiensis (Balke, 1998).

Additions to the description

(original description in Balke 1998, p. 327). Size and shape: Beetles small to medium-sized (TL-H 3.2-4.0 mm, TL 3.7-4.4 mm, MW 1.75-2.15 mm; holotype: TL-H 3.55 mm, TL 3.9 mm, MW 1.9 mm). Male: Protarsomere 4 with large, thick, strongly curved anterolateral hook-like seta. Protarsomere 5 ventrally with anterior row of 14 and posterior row of 5 short setae (Fig. 8A). Abdominal ventrite 6 with 3-6 lateral striae on each side. Median lobe with slightly curved apex in lateral view and more or less rounded in ventral view. Its ventral sclerite with almost equal, short apical lobes: left lobe broad or narrow (sometimes with broken apex, e.g., Fig. 9A) and right lobe short, relatively broad (Fig. 8B, C).

Variability: Beetles vary in size, kind of dorsal punctation (Figs 1-3), and shape of ventral sclerite of the median lobe (Fig. 9 A–E). Dorsal punctation in great majority of the specimens is fine (Fig. 3), but some specimens have slightly coarser punctation, and very few (the types and one specimen from Simbai area, Madang, see Figs 1, 2) have distinct punctation, similar to that of Exocelina pseudomarinae sp. n. There are populations (e.g., from Simbai area, Madang, and Akameku-Brahmin, Eastern Highlands) with the left lobe of the ventral sclerite of the median lobe very narrow (Fig. 9A, B). However, this character is not very stable even in one population. Taking into consideration the other different shapes of the ventral sclerite observed (Figs 8B, 9 C–E) as well as the fact that it is differently sclerotized in different specimens and because of that is variable in shape, we treated all the material as Exocelina broschii . Such variability in shape of the ventral sclerite of the median lobe is also characteristic for other species of this group (Figs 9, 10, 12).

Distribution.

Papua New Guinea: Madang and Eastern Highlands Provinces (Fig. 14).