Exocelina aipomek (Balke, 1998)

Shaverdo, Helena, Surbakti, Suriani, Warikar, Evie L., Sagata, Katayo & Balke, Michael, 2019, Nine new species groups, 15 new species, and one new subspecies of New Guinea diving beetles of the genus Exocelina Broun, 1886 (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 878, pp. 73-143 : 73

1. Exocelina aipomek (Balke, 1998) Figs 1 , 5 , 6-7

Copelatus (Papuadytes) aipomek Balke, 1998: 322; Nilsson 2001: 76 (catalogue).

Papuadytes aipomek (Balke, 1998): Nilsson and Fery 2006: 56 (comb. nov.).

Exocelina aipomek (Balke, 1998): Nilsson 2007: 33 (comb. nov.).

Exocelina aipomek MB3726: Toussaint et al. 2014: supplementary figs 1-4, tab. 2; Toussaint et al. 2015: supplementary figs S1, S2, tab. S3, and information S5, S6.

Copelatus (Papuadytes) santimontis Balke, 1998: 335; Nilsson 2001: 77 (catalogue) syn. nov.

Papuadytes santimontis (Balke, 1998): Nilsson and Fery 2006: 56 (comb. nov.).

Exocelina santimontis (Balke, 1998): Nilsson 2007: 34 (comb. nov.).

Type locality.

Indonesia: Papua Province: Pegunungan Bintang Regency, Aipomek, 04°27'S, 140°01'E, 1800 m a.s.l.

Type material studied.

Exocelina aipomek : Holotype: male "IRIAN JAYA Aipomek Area 140°01'E 04°27'S ", "Aipomek, 1800m 30./31.8.1992 leg.Balke (30)", “HOLOTYPUS” [red], " Copelatus aipomek Balke des. 1997" [red] (NHMW). Paratypes: 3 males, 1 female with the same label as the holotype and additionally with red labels "Paratypus Copelatus aipomek Balke des. 1997", one of the males with two additional labels "M.Balke 3272" [green] and "M.Balke 6403 DNA" [green text] (NHMW). Exocelina santimontis : Holotype: male "IRIAN JAYA: 1.10.1993 Eme Gebiet Okloma, 1500m", "ca. 139°55'E 04°14'S leg. M. Balke (28)", “HOLOTYPUS” [red], " Copelatus santimontis Balke des. 1997" [red] (NHMW). Paratypes: 8 males with the same label as the holotype and additionally with red labels "Paratypus Copelatus santimontis Balke des. 1997", one of the males with two additional labels "M.Balke 3289" [green] and "M.Balke 6412 DNA" [green text], another male with an additional green label "M.Balke 3288" (NHMW). 1 male "IRIAN JAVA: Borme Tarmlu 1500m 6.9.1993", "ca. 140°25'E 04°24'S leg. M. Balke (4 –6)”, "Paratypus Copelatus santimontis Balke des. 1997" (NHMW). 1 male "IRIAN JAYA: 22.9.1993 Bime - Calab Gebiet, Bime, 1400m", "ca. 140°12'E 04°20'S, leg. M. Balke (16)", "Paratypus Copelatus santimontis Balke des. 1997" [red] (NHMW)

Additional material.

PNG: Sandaun: 2 males "Papua New Guinea: Sandaun, Ofektaman, 820m, 17.x.2008, 5.04.113S 141.35.841E, Ibalim (PNG 190)", one with an additional green label "M.Balke 3727" (ZSM).

Females of doubtful identity.

IN: Papua: Pegunungan Bintang: 20 females "IRIAN JAYA: 22.9.1993 Bime - Calab Gebiet, Bime, 1400m", "ca. 140°12'E 04°20'S, leg. M. Balke (16)", "Paratypus Copelatus rivulus sp.n. Balke des. 1997" [red] (NHMW); these females are a mixture of two species: E. damantiensis (Balke, 1998) and E. aipomek . 13 females "IRIAN JAYA: 22.9.1993 Bime - Calab Gebiet, Bime, 1400m", "ca. 140°12'E 04°20'S, leg. M. Balke (16)" (NHMW); these females are a mixture of two species: E. damantiensis and E. aipomek . 1 female "IRIAN JAVA: Borme Tarmlu 1500m 6.9.1993", "ca. 140°25'E 04°24'S leg. M. Balke (4 –6)” (NHMW). 3 females "IRIAN JAVA: Borme Tarmlu 1500m 6.9.1993", "ca. 140°25'E 04°24'S leg. M. Balke (4)" (NHMW). 2 females "IRIAN JAVA: Borme Tarmlu 1500m 6.9.1993", "ca. 140°25'E 04°24'S leg. M. Balke (6)" (NHMW). These females are a mixture of four species: E. damantiensis , E. ketembang (Balke, 1998), E. aipomek , and E. danae (Balke, 1998). 1 male (no genitals), 27 females "IRIAN JAYA: 1.10.1993 Eme Gebiet Okloma, 1500m", "ca. 139°55'E 04°14'S, leg. M. Balke (28)" (NHMW); these specimens are a mixture of three species: E. damantiensis , E. ketembang , and E. aipomek . 13 females "IRIAN JAYA: 22.9.1993 Bime - Calab Gebiet, Bime, 1400m", "ca. 140°12'E 04°20'S, leg. M. Balke (16)" (NHMW). 2 females "IRIAN JAYA, 24.-26.9.1993 Eipomek [sic!] Gebiet Eipomek [sic!] - Diruemna", "ca. 140°01'E 04°27'S 1800-2600m, leg. M. Balke (21 –22)” (NHMW). These females are a mixture of two species: E. damantiensis and E. aipomek . PNG: Sandaun: 7 females "Papua New Guinea: Sandaun, Ofektaman, 820m, 17.x.2008, 5.04.113S 141.35.841E, Ibalim (PNG 190)" (ZSM); these females might belong to three species: E. sandaunensis Shaverdo & Balke, 2014, E. aipomek , and E. ketembang (Balke, 1998).

Diagnosis.

For complete description, see Balke (1998: 322). Beetle medium-sized (TL-H 4.0-4.35 mm), oblong-oval; piceous, sometimes with paler pronotal sides; dorsally shiny, with extremely fine, inconspicuous punctation and weakly impressed microreticulation; pronotum with distinct lateral bead ( Fig. 1 ); male protarsomere 4 with large, thick, strongly curved anterolateral hook-like seta; male protarsomere 5 ventrally with anterior band of more than 60 and posterior row of 14 relatively long setae ( Fig. 5D ); median lobe simple, in lateral view, evenly tapering to broadly pointed, somehow elongate and gently curved downwards apex, in ventral view, apex more or less rounded; paramere with distinct dorsal notch and large, long subdistal part, dorsal setae numerous and strong, subdistal slightly denser and longer than proximal ones, the latter more or less distinct ( Fig. 5 A–C ).

Variability.

The species shows variability within and between populations in shape of the apex of the median lobe, which can be shorter or more elongate ( Figs 6 , 7 ).

Affinities.

In the area of its distribution, E. aipomek co-occurs with numerous species: E. ascendens (Balke, 1998), E. fume (Balke, 1998), E. takime , species of the E. bacchusi , E. ekari , E. danae , E. broschii , E. okbapensis , and E. aipo groups. The species can be distinguished from them by its body size, form and colouration, inconspicuous dorsal punctation, and weakly impressed microreticulation, presence of the pronotal bead, shape and setation of its median lobe, paramere, and male protarsomere 4.

Distribution.

Indonesia: Papua Province: Pegunungan Bintang Regency and Papua New Guinea: Sandaun Province ( Fig. 11 ).

Figures

Figure 5. Exocelina aipomek (Balke, 1998), paratype A median lobe in ventral view B median lobe in lateral view C paramere in external view D male protarsomeres 4 - 5 in ventral view.

Figure 11. Map of the eastern part of New Guinea showing distribution of the species of the monotypic groups.

Figures 1 - 4. Habitus and colouration 1 Exocelina aipomek (Balke, 1998) 2 E. mekilensis sp. nov. 3 E. koroba sp. nov. 4 E. morobensis sp. nov.

Figures 6, 7. Exocelina aipomek (Balke, 1998), median lobe in lateral view 6 specimen from Sandaun, Ofektaman 7 paratype of E. sanctimontis (Balke, 1998).