Research Article |
Corresponding author: Helena Shaverdo ( shaverdo@mail.ru ) Academic editor: Mariano Michat
© 2018 Helena Shaverdo, Katayo Sagata, Michael Balke.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Shaverdo H, Sagata K, Balke M (2018) Introduction of the Exocelina casuarina-group, with a key to its representatives and descriptions of 19 new species from New Guinea (Coleoptera, Dytiscidae, Copelatinae). ZooKeys 803: 7-70. https://doi.org/10.3897/zookeys.803.28903
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Nineteen new species of Exocelina Broun, 1886 from New Guinea are described herein: E. adelbertensis sp. n., E. ambua sp. n., E. bewani sp. n., E. cyclops sp. n., E. ibalimi sp. n., E. keki sp. n., E. kumulensis sp. n., E. mendiensis sp. n., E. menyamya sp. n., E. okapa sp. n., E. piusi sp. n., E. pseudofume sp. n., E. pseudopusilla sp. n., E. pusilla sp. n., E. sima sp. n., E. simbaiensis sp. n., E. simbaijimi sp. n., E. sumokedi sp. n., and E. yoginofi sp. n. All of them, together with five already described species, have been united into the newly defined casuarina-group, a polyphyletic complex of related species with similar shape of the median lobe and paramere setation. An identification key to all known species of the group is provided, and important diagnostic characters (habitus, color, male protarsomeres 4–5, median lobes, and parameres) are illustrated. Data on the distribution of the species are given, showing that most of the species occur in the central, mountain part of Papua New Guinea.
Copelatinae , Dytiscidae , Exocelina casuarina-group, key, New Guinea, new species
Herein, we introduce the new species group of the genus Exocelina Broun, 1886. After the ekari-group with 51 species, it is the second largest species group of the New Guinea Exocelina (
Including the results of this work, 125 species of Exocelina are described from New Guinea and 180 species worldwide.
As in most of our previous papers on the genus (
The present work is based on material from the following collections:
CLH Collection of Lars Hendrich, Munich, Germany (property of
All methods follow those described in detail in our previous articles (
Abbreviations: IN Indonesia; PNG Papua New Guinea.
Species | Distribution | |
---|---|---|
1. | Exocelina adelbertensis sp. n. | PNG: Madang |
2. | Exocelina ambua sp. n. | PNG: Southern Highlands |
3. | Exocelina bewani sp. n. | PNG: Sandaun |
4. | Exocelina casuarina (Balke, 1998) | IN: Papua: Nabire |
5. | Exocelina cyclops sp. n. | IN: Papua: Jayapura |
6. | Exocelina desii (Balke, 1999) | PNG: East Sepik, Simbu, Eastern and Western Highlands |
7. | Exocelina fume (Balke, 1998) | IN: Papua: Pegunungan Bintang |
8. | Exocelina heidiae (Balke, 1998) | PNG: Morobe |
9. | Exocelina ibalimi sp. n. | PNG: Sandaun |
10. | Exocelina keki sp. n. | PNG: Madang, Eastern Highlands |
11. | Exocelina kumulensis sp. n. | PNG: Enga |
12. | Exocelina mendiensis sp. n. | PNG: Southern Highlands |
13. | Exocelina menyamya sp. n. | PNG: Morobe |
14. | Exocelina messeri (Balke, 1999) | PNG: East Sepik |
15. | Exocelina okapa sp. n. | PNG: Eastern Highlands |
16. | Exocelina piusi sp. n. | PNG: East Sepik |
17. | Exocelina pseudofume sp. n. | PNG: Madang |
18. | Exocelina pseudopusilla sp. n. | PNG: Simbu |
19. | Exocelina pusilla sp. n. | PNG: Madang, Simbu |
20. | Exocelina sima sp. n. | PNG: Eastern Highlands, Simbu |
21. | Exocelina simbaiensis sp. n. | PNG: Western Highlands |
22. | Exocelina simbaijimi sp. n. | PNG: Western Highlands |
23. | Exocelina sumokedi sp. n. | IN: Papua: Puncak |
24. | Exocelina yoginofi sp. n. | PNG: Eastern Highlands |
The diagnostic characters of the group are:
– beetles small or medium-sized (TL-H 2.7–5.5 mm);
– habitus elongate to oval, in most species oblong-oval (broadest approximately at elytral midlength); with rounded pronotal and elytral sides, body outline continuous;
– pronotum short, trapezoidal, with posterior angles not drawn backwards;
– coloration reddish to piceous, mainly uniform, sometimes with paler head and pronotum and darker elytra;
– microreticulation and punctation of dorsal surface very fine to strongly impressed, beetles shiny to matt dorsally;
– metacoxae and abdominal ventrites 1–5 (and 6 in males) with thin, almost longitudinal striae/strioles;
– pronotum and elytra without striae or strioles;
– pronotum with or without lateral bead;
– antennomeres not modified;
– male protarsomeres 1–3 not expanded laterally;
– male protarsomere 4 cylindrical, narrow, with anterior angle slightly expanded in some species, with a large, hook-like to thin, long, slightly curved anterolateral seta;
– male protarsomere 5 long and narrow, sometimes slightly concave ventrally;
– median lobe of aedeagus with continuous outline in ventral and lateral view; almost straight or slightly curved in lateral view; in ventral view, almost parallel-sided, often narrowed distally before apex or towards it, or broadened subdistally; apex usually with thickened sides, slightly or distinctly enlarged (“swollen”, often ventrally of shape of a baby pacifier), rounded, truncate, or slightly concave in ventral view;
– ventral sclerite of median lobe more or less deeply divided apically;
– median lobe without setation, in some species with minuscule spines;
– paramere without dorsal notch and with long, dense, thin setae, situated along dorsal margin, subdistal setae usually denser and stronger than proximal ones.
Although the species of the group do not form a monophyletic complex with the distinguished autapomorphic morphological character (Fig.
Phylogenetically, the group is polyphyletic and includes five different clades, which are partially supported morphologically and contribute to two larger monophyletic complexes: 1) clades I and II plus the okbapensis-group and 2) clades III, IV, and V plus two monotypic groups (two undescribed species, which are very different morphologically from all the other species of the clades) (Fig.
Clade I includes E. simbaiensis sp. n., E. yoginofi sp. n. and, probably, E. okapa sp. n. (based on morphology). These species build a monophyletic complex with the species of the okbapensis- and aipo-groups. Interestingly, the two latter species demonstrate a distinct similarity with the species of the okbapensis-group in the shape of the median lobe and setation of paramere, though E. simbaiensis sp. n. does not.
Clade II is morphologically rather heterogeneous and is comprised of the largest (size) representatives of the group. Three of them, E. desii, E. simbaijimi sp. n. and, probably, E. heidiae (based on morphology), form a monophyletic complex and have broad, similar in shape median lobes. The remainder have median lobes distinctly narrower and more different in shape.
Clade III includes species without lateral pronotal bead, except for Exocelina piusi sp. n., which has narrow but distinct pronotal bead and seems to form a separate lineage. There are two monophyletic complexes in the clade: 1) E. casuarina, E. fume, and E. ibalimi sp. n. with a large, hook-like anterolateral seta of the male protarsomere 4 and 2) E. keki sp. n. and E. pseudofume sp. n. with a thin, long, slightly curved anterolateral seta of the male protarsomere 4, as well as E. messeri and E. sima sp. n., which also have a similar shape of this seta. The representatives of this clade best demonstrate a “swollen” apex of the median lobe.
Clade IV is the most homogeneous and includes the smallest in size species of the group. They are morphologically very similar, and three of them, E. cyclops sp. n., E. bewani sp. n., and E. adelbertensis sp. n., are a good example of recent allopatric speciation along the north coast of New Guinea (
Clade V includes two very different species. Exocelina menyamya sp. n. is the most uncharacteristic representative of the group because the apex of its median lobe is thin, flattened, and with ventral impression. The second species is E. pusilla sp. n., one of the smallest species of the group. Based on its size and coloration, this species could have been placed into the clade IV but the molecular analysis, as well as the shape of its median lobe, showed that it is a separate lineage of inland mountain Exocelina. Most likely E. pseudopusilla sp. n. belongs to this clade too. This species is very similar to E. pusilla sp. n., but larger and more elongate, with denser and coarser dorsal punctation and microreticulation and different shape of the median lobe (for more details on species delimitation, see the species descriptions). Exocelina pusilla sp. n. has wider distribution. Both species are known from the Mount Wilhelm, but from different altitudes: E. pusilla sp. n. only from 200 m (from other localities, it is known from up to 500 m) and E. pseudopusilla sp. n. only from 1200 m. If this species delimitation is correct, then this is the first distinct example in Exocelina of altitudinal peripatric speciation, which is also assumed for the Exocelina species of Weyland area (
Thus, this group, as defined now, is the subject of further study and may be divided into subgroups or even groups as and when additional species are discovered.
Exocelina
undescribed sp. MB1297:
Exocelina
adalbert
_New_Guinea_MB1297:
Papua New Guinea: Madang Province, Adelbert Mts, Keki to Sewan, 04°41.80'S, 145.25.46'E, 650 m a.s.l.
Holotype: male “Papua New Guinea: Madang, Adalbert [sic!] Mts., Keki to Sewan, 650m, 7.v.1994, 04.41.802S 145.25.460E, Balke (PNG 54)”, “M.Balke 1297” [green] (
Body size and form: Beetle small: TL-H 3.1 mm, TL 3.4 mm, MW 1.9 mm, with broader, oval habitus.
Coloration: Brownish, with head and pronotum paler. Head reddish brown, darker posterior to eyes. Pronotum reddish brown on sides, dark brown on disc. Elytra brown. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. As in E. sumokedi sp. n., except for more strongly impressed microreticulation.
Structures: Pronotum with lateral bead. Its lateral sides with longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 slightly truncate.
Male: Antennae simple (Fig.
Female: Unknown.
Exocelina adelbertensis sp. n. is very similar to E. sumokedi sp. n. and E. bewani sp. n. but it has slightly more strongly impressed microreticulation, therefore, dorsal surface is distinctly less shiny. Median lobe is more thickened, similar to that of E. sumokedi sp. n. but its apex is curved downwards and with stronger terminal angulation. The species is also similar to E. cyclops sp. n., E. pseudopusilla sp. n., and E. pusilla sp. n., see their “Affinities” and the “Key”.
Papua New Guinea: Madang Province. The species is known only from the type locality (Fig.
The species is named after Adelbert Mountains. The species name is an adjective in the nominative singular.
Exocelina
undescribed sp. MB1290:
Exocelina
ambuaensis
_New_Guinea_MB1290:
Papua New Guinea: Southern Highlands Province, Tari, Mt Ambua, 05°57.55'S, 143°04.99'E, 2,100 m a.s.l.
Holotype: male “Papua New Guinea: Southern Highlands, Tari, Mt Ambua, 2100m, 14.v.2006, 05.57.550S 143.04.993E, Balke (PNG 64)” (
Body size and form: Beetle medium-sized: TL-H 4.3–4.7 mm, TL 4.8–5.2 mm, MW 2.2–2.5 mm (holotype: TL-H 4.4 mm, TL 4.8 mm, MW 2.3 mm), with oblong habitus.
Coloration: Brown to piceous, with head and pronotum paler. Head reddish brown to piceous, with small darker areas posterior to eyes. Pronotum dark brown to piceous, paler on sides and darker on disc. Elytra dark brown to piceous, with vague narrow reddish to brownish sutural lines. Head appendages and legs proximally reddish brown, legs distally darker, brownish, especially metathoracic legs (Fig.
Surface sculpture: Matt dorsally. Head with dense, coarse punctation (no spaces between punctures or spaces 2 times size of punctures), finer and sparser anteriorly; diameter of punctures equal to diameter of cells of microreticulation. Pronotum and elytra with dense, coarse punctation, sparser and finer than on head. Pronotum and elytra with strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles, abdominal ventrites with distinct microreticulation and strioles. Metaventrite medially, metacoxal plates, and abdominal ventrites with fine, sparse punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, and smooth, with distinct lateral bead and few lateral setae. Abdominal ventrite 6 slightly truncate.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina ambua sp. n. is similar to E. mendiensis sp. n. but differs from it in smaller size, coarser and denser dorsal punctation and microreticulation, and shape of the median lobe.
Papua New Guinea: Southern Highlands Province. The species is known only from the type locality (Fig.
The species is named after Mt Ambua. The name is a noun in the nominative singular standing in apposition.
Exocelina
undescribed sp. MB1296:
Exocelina
bewani
_New_Guinea_MB1296:
Papua New Guinea: Sandaun Province, Bewani Mts, approximately 03°05.13'S, 141°10.23'E., 400 m a.s.l.
Holotype: male “Papua New Guinea: Sandaun, Bewani Stn., limestone creek@base of Bewani Mts., 400 m, 12.iv.2006, nr. 03.05.130S 141.10.227E, Balke & Sagata (PNG 39)”, “M.Balke 1296” [green] (
Body size and form: Beetle small: TL-H 3.05–3.25 mm, TL 3.35–3.55 mm, MW 1.8–1.9 mm (holotype: TL-H 3.05 mm, TL 3.35 mm, MW 1.8 mm), with broader, oval habitus.
Coloration: Brownish, with head and pronotum paler. Head reddish brown to brownish, sometimes paler anteriorly. Pronotum reddish brown on sides, brown to dark brown on disc. Elytra brown to dark brown, sometimes with narrow reddish sutural lines. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Shiny but with dense, distinct punctation dorsally. As in E. sumokedi sp. n.
Structures: Pronotum with lateral bead. Its lateral sides with shallow longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, narrowly rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 slightly truncate.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina bewani sp. n. is very similar to E. sumokedi sp. n. but is larger and has a less striated abdominal ventrite 6; also, its median lobe is not narrowed distally in ventral view and with apex broad and slightly concave ventrally and curved downwards in lateral view. The species is also similar to E. adelbertensis sp. n., E. cyclops sp. n., E. pseudopusilla sp. n., and E. pusilla sp. n., see their “Affinities” and the “Key”.
Papua New Guinea: Sandaun Province. The species is known only from the type locality (Fig.
The species is named after the Bewani Mountains. The name is a noun in the nominative singular standing in apposition.
Copelatus (Papuadytes) casuarinus
Balke & Hendrich, 1998 in
Papuadytes
casuarinus
(Balke & Hendrich, 1998):
Exocelina
casuarina
(Balke & Hendrich, 1998):
Papua: Nabire Regency, 62 km of road Nabire to Enarotali, ca 03°30.936'S, 135°42.945'E, 250 m a.s.l. Note: the road only goes up to Enarotali, Ilaga is much further in the mountains, therefore, people now refer to the road as Nabire-Enarotali.
Holotype: male “IR 23-W. New Guinea, track Nabire-Ilaga, KM 62, 250m, 24.vii.1991 Balke & Hendrich leg.”, “HOLOTYPUS” [red], “Copelatus casuarinus Balke des. 1997” [red] (
1 female “IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 65 29.8.1996, 250m leg. M. Balke (96 # 6)” (
For complete description, see
Exocelina casuarina is the only species of the casuarina-group in Nabire Regency. In this area, Exocelina is represented mainly by the species of the ekari-group, which are small in size and have no pronotal bead. From them, as well as from E. ransikiensis
Within the casuarina-group, the species is more similar to E. fume (Balke, 1998) and E. ibalimi sp. n., with which it shares not only absence of the pronotal bead, but also a large, strongly curved anterolateral hook-like seta of the male protarsomere 4 (see their “Affinities” and the “Key”).
Papua: Nabire Regency. The species is known only from the area close to the type locality (Fig.
Exocelina
undescribed sp. MB3330:
Exocelina
cyclops
New Guinea MB3330:
Papua: Jayapura Regency, Cyclops Mts, 02°32.03'S, 140°30.41'E, 710 m a.s.l.
Holotype: male “Indonesia: Papua, Cyclops Mts., 710 m, 02°32.031'S, 140°30.412'E, local collector ca. 1997” (
Body size and form: Beetle small: TL-H 3.0–3.25 mm, TL 3.25–3.55 mm, MW 1.65–1.8 mm (holotype: TL-H 3.1 mm, TL 3.4 mm, MW 1.7 mm), with oblong-oval habitus.
Coloration: Reddish. Dorsal surface almost uniformly yellowish red to reddish brown, with paler anterior part of head and pronotum laterally; head appendages and legs yellowish red (Fig.
Surface sculpture: Submatt dorsally. As in E. pseudopusilla sp. n. but microreticulation more weakly impressed, dorsal surface shinier.
Structures: Pronotum with lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 slightly truncate.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina cyclops sp. n. is similar to E. sumokedi sp. n., E. adelbertensis sp. n., and E. bewani sp. n., but has coarser dorsal punctation. In this character, the species is more similar to E. pusilla sp. n. and E. pseudopusilla sp. n. but it differs from them in much broader and differently shaped median lobe (not distinctly narrowed distally, with apex thicker in lateral and ventral views) and from the latter, also in smaller size and slightly shinier dorsal surface.
Papua: Jayapura Regency. The species is known only from the Cyclops Mountains (Fig.
The species is named after the Cyclops Mountains. The name is a noun in the nominative singular standing in apposition.
Copelatus (Papuadytes) desii
Balke, 1999: 274;
Papuadytes
desii
(Balke, 1999):
Exocelina
desii
(Balke, 1999):
Exocelina
desii
MB1399:
Papua New Guinea: East Sepik Province, Amboin Patrol Post, Karawari Lodge, ca 04°29'05.8"S, 143°26'37.5"E, < 100 m a.s.l.
Paratype: female “Papau [sic!] New Guinea East Sepik Province, Amboin Patrol Post, Karawari Lodge 14Jan.1983, A.C.Messer”, “Paratypus Copelatus desii M. Balke des. 1999” [red] (
Western Highlands: 3 females “Papua New Guinea: Western Highlands, Mt. Hagen town area, 1600m, 7.xii.1994 05.49.745S 144.22.357E Balke & Kinibel (PNG 131)” (
For complete description, see
In the area of its distribution, E. desii co-occurs with numerous species of the ekari-, ullrichi-, broschii-, larsoni-, and danae-groups. From them, the species differs in size, coloration, surface sculpture, simple male antennae, and the shape of the median lobe.
Within the casuarina-group, it is very similar in coloration and surface sculpture to the co-occurring E. pusilla sp. n. and E. pseudopusilla sp. n. but can be distinguished from them by larger size and evidently thicker median lobe.
Papua New Guinea: East Sepik, Simbu, Western Highlands, and Eastern Highlands Provinces (Fig.
Copelatus (Papuadytes) fume
Balke, 1998: 330;
Papuadytes
fume
(Balke, 1998):
Exocelina
fume
(Balke, 1998):
Papua: Pegunungan Bintang Regency, Borme, 04°24'S, 140°25'E, 1800 m a.s.l.
Holotype: male “IRIAN JAYA Zentralmassive 140°25'E 04°24'S, “Borme, 1800m 16.8.1992 leg. Balke (12, 12A)”, “HOLOTYPUS” [red], “Copelatus fume Balke des. 1997” [red] (
For complete description, see
In the area of its distribution, E. fume co-occurs with E. takime (Balke, 1998) and species of the ekari-, aipo-, okbapensis-, aipomek-, erteldi-, and danae-groups. From species of the ekari-group, the species differs in larger size, evidently stronger dorsal punctation and microreticulation, and the shape of the median lobe. In the latter two characters, E. fume differs also from the species of the remaining groups, as well as in absence of the pronotal bead and simple male antennae.
Within the casuarina-group, the species is more similar to E. casuarina and E. ibalimi sp. n., especially the latter one, from which can be distinguished by paler coloration and the shape of the median lobe (see their “Affinities” and the “Key”).
Papua: Pegunungan Bintang. The species is known only from the type locality (Fig.
Copelatus (Papuadytes) heidiae
Balke, 1998: 331;
Papuadytes
heidiae
(Balke, 1998):
Exocelina
heidiae
(Balke, 1998):
Papua New Guinea: Morobe Province, Herzog Range, Wagau (Vagau), ca 06°48'S, 146°48'E, ca 1300 m a.s.l.
Paratypes: 3 males “Stn. No. 150”, “New Guinea: Morobe Dist., Herzog Mts., Vagau, C.4,000ft. 4–17.i.1965”, “M. E. Bacchus. B. M. 1965–120”, “Paratypus Copelatus heidiae sp.n. Balke des. 1997” [red] (
For complete description, see
In the Herzog Range area, E. heidiae co-occurs with Exocelinajasminae (Balke, 1998), two species of the ekari-group, and four species of the danae-group. From all of them, the species differs in larger size and the shape of the median lobe. Additional characters for the species separations are presence of the pronotal bead, simple male antennae, and dorsal punctation and microreticulation.
Within the casuarina-group, the species is more similar to E. simbaijimi sp. n. (see its “Affinities” and the “Key”).
Papua New Guinea: Morobe Province. The species is known only from the type locality, Wagau in Herzog Range (Fig.
Exocelina
undescribed sp. MB0657:
Exocelina
ibalimi
_New_Guinea_MB0657:
Papua New Guinea: Sandaun Province, Mianmin area, ca 04°55.78'S, 141°38.18'E, 1080 m a.s.l.
Holotype: male “Papua New Guinea: Sandaun, Mianmin area, >600m, 13.i.2010, Ibalim & Pius (PNG235)” (
Body size and form: Beetle size variable but generally beetle medium-sized: TL-H 3.45–4.3 mm, TL 3.75–4.8 mm, MW 1.8–2.25 mm (holotype: TL-H 4.15 mm, TL 3.75 mm, MW 2 mm), with oblong-oval habitus, slightly more attenuated posteriorly.
Coloration: Brown to piceous, with head and pronotum paler. Head reddish brown to piceous, darker posteriorly. pronotum reddish brown to piceous, broadly paler on lateral sides and sometimes also narrowly anteriorly and posteriorly. Elytra uniformly brown to piceous. Head appendages and legs yellowish red to reddish brown, legs distally darker, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. Head with rather dense punctation (spaces between punctures 1–2 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures smaller than diameter of cells of microreticulation. Pronotum and elytra with fine but rather dense punctation, sparser and finer than on head. Pronotum and elytra with strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine sparse punctation.
Structures: Pronotum without lateral bead. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 broadly rounded or slightly truncate.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
The species has variability in size, coloration and shape of the median lobe. Beetles are small to medium-sized (see the measurements above) and with coloration: from reddish head and pronotum and dark brown elytra to uniformly piceous with reddish brown pronotal sides. Median lobe shows different shape of its apex: in lateral view, it is not curved or differently slightly curved downwards reminding that of E. fume but without distinct angle.
Exocelina ibalimi sp. n. is very similar to E. fume but differs from it in shape of the median lobe: its apex not curved or only slightly curved downwards, more or less rounded in lateral view, without distinct angle on the dorsal side. The species also has dorsal punctation distinctly finer and microreticulation less strongly impressed than in E. fume.
Papua New Guinea: Sandaun Province (Fig.
The species is named for Sentiko Ibalim, one of the great young PNG entomologists, who collected most of these beetles. The species name is a noun in the genitive case.
Exocelina
undescribed sp. MB1530:
Exocelina
pseudokeki
_New_Guinea_MB1530:
Papua New Guinea: Madang, Adelbert Mts, creek near Keki, 04°42.30'S, 145°25.09'E, 790 m a.s.l.
Holotype: male “Papua New Guinea: Madang, Keki, Adalbert [sic!] Mts., 500m, 29.xi.2006, nr 04.43.058S 145.24.437E, Balke & Kinibel (PNG 118)” (
Body size and form: Beetle small: TL-H 3.15–3.65 mm, TL 3.45–4.0 mm, MW 1.65–1.9 mm (holotype: TL-H 3.65 mm, TL 4 mm, MW 1.85 mm), with oblong habitus.
Coloration: Reddish to reddish brown, with head and pronotum paler. Head yellowish red to reddish brown, with small darker areas posterior to eyes. Pronotum yellowish red to reddish brown, with small brown to dark brown area on disc. Elytra reddish brown to brown, with narrow reddish sutural lines. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. Head with rather dense punctation (spaces between punctures 1–2 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures smaller than diameter of cells of microreticulation. Pronotum and elytra with dense, distinct but fine punctation, sparser and finer than on head. Pronotum and elytra with strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine sparse punctation.
Structures: Pronotum without lateral bead, in few specimens with its traces in posterior part. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 rounded.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Papua New Guinea: Madang and Eastern Highlands (Fig.
Exocelina keki sp. n. is very similar to Exocelina messeri (Balke, 1999) in body form and coloration, but has much more distinct dorsal punctation and stronger microreticulation, as well as median lobe more slender, with apex smaller and narrower in ventral view; the ventral setae of male protarsomere 5 are much less numerous and clearly divided into anterior band and posterior row.
species is named after Keki Village. The name is a noun in the nominative singular standing in apposition.
Exocelina
undescribed sp. MB1360:
Exocelina
hagenensis
_New_Guinea_MB1360:
Papua New Guinea: Enga Province, Kumul Lodge at foot of Mt Hagen, 05°47.55'S, 143°58.76'E, 2700 m a.s.l.
Holotype: male “M. Balke 1360” [green], “Papua New Guinea: Enga, Kumul Lodge @ foot of Mt. Hagen, 2700m, 5.xii.2006, 05.47.548S 143.58.761E, Balke & Kinibel (PNG 124)” (
Body size and form: Beetle large: TL-H 5.4 mm, TL 6.0 mm, MW 2.9 mm, with broader, oblong-oval habitus.
Coloration: Piceous, with paler pronotum. Head piceous, narrowly brownish anteriorly and with two vague brownish spots between eyes. Pronotum dark brown, piceous on disc. Elytra piceous, with vague narrow brownish sutural lines. Head appendages and legs proximally reddish brown, legs distally darker, brownish, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. Head with dense, coarse punctation (no spaces between punctures or spaces of equal size of punctures), finer and sparser anteriorly; diameter of punctures equal to diameter of cells of microreticulation. Pronotum with relatively dense but fine punctation, sparser and finer than on head. Elytra with finer punctation than on pronotum. Pronotum and elytra with strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles, abdominal ventrites with distinct microreticulation and strioles. Metaventrite medially, metacoxal plates, and abdominal ventrites with fine, sparse punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively short, broad, slightly convex and smooth in the middle, with distinct lateral bead and few lateral setae, lateral sides flattened. Abdominal ventrite 6 rounded.
Male: Antennae simple (Fig.
Female: Unknown.
Exocelina kumulensis sp. n. is similar to E. mendiensis sp. n. but differs from it by being larger, having coarser and denser dorsal punctation and by the shape of the median lobe.
Papua New Guinea: Enga Province. The species is known only from the type locality (Fig.
The species is named after Kumul Lodge. The name is an adjective in the nominative singular.
Exocelina
undescribed sp. MB1337:
Exocelina
mendiensis
_New_Guinea_MB1337:
Papua New Guinea: Southern Highlands Province, Sopulkul, 30–35 km NE Mendi, 06°02.94'S, 143°46.49'E, 2680 m a.s.l.
Holotype: male “M. Balke 1337”, “Papua New Guinea: Southern Highlands, Sopulkul, 30–35 km NE Mendi, 2680 m, 16.vi.2006, 06.02.944S 143.46.485E, John (PNG 79)” (
Body size and form: Beetle large: TL-H 4.8–5.5 mm, TL 5.3–5.9 mm, MW 2.6–2.75 mm (holotype: TL-H 4.8 mm, TL 5.3 mm, MW 2.6 mm), with broader, oblong-oval habitus.
Coloration: Piceous. Head piceous, narrowly brownish anteriorly and sometimes with two brownish spots between eyes. Pronotum piceous, brownish laterally and anteriorly. Elytra piceous, sometime with narrow brownish sutural lines. Head appendages and legs proximally reddish brown, legs distally darker, brownish, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. Head with relatively dense punctation (no spaces between punctures or spaces 2 times size of punctures), sparser anteriorly, denser and coarser between eyes; diameter of punctures smaller than or equal to diameter of cells of microreticulation. Pronotum with relatively dense but fine punctation, sparser and finer than on head. Elytra with very fine, sparse punctation. Pronotum and elytra with rather strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles, abdominal ventrites with distinct microreticulation and strioles. Metaventrite medially, metacoxal plates, and abdominal ventrites with very fine, sparse punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, and smooth, with distinct lateral bead and few lateral setae. Abdominal ventrite 6 slightly truncate.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina mendiensis sp. n. is similar to the larger species of the group, E. kumulensis sp. n. and E. ambua sp. n., but differs from them in its darker coloration, shinier dorsal surface and shape of the median lobe. Also, see under E. okapa sp. n.
Papua New Guinea: Southern Highlands Province. The species is known only from the type locality (Fig.
The species is named after Mendi Village. The name is an adjective in the nominative singular.
Exocelina
undescribed sp. MB1377:
Exocelina
menyamya
_New_Guinea_MB1377:
Papua New Guinea: Morobe Province, Menyamya, Mount Inji, 07°14.26'S, 146°01.40'E, 1500 m a.s.l.
Holotype: male “Papua New Guinea: Morobe, Menyamya, Mt Inji, deep well, 1500m, 14.xi.2006, 07.14.264S 146.01.400E, Balke & Kinibel (PNG 98)”, “M.Balke 1377” [green] (
Body size and form: Beetle medium-sized: TL-H 4.25 mm, TL 4.8 mm, MW 2.2 mm, with oblong-oval habitus.
Coloration: Brown, with reddish pronotum. Head brown, with slightly darker areas posterior to eyes. Pronotum broadly reddish laterally and dark brown medially from anterior to posterior margins. Elytra uniformly brown, in the middle with traces of narrow reddish sutural lines. Head appendages and legs proximally yellowish red, legs distally darker, reddish brown, especially metathoracic legs (Fig.
Surface sculpture: Matt dorsally. Head with rather dense, coarse punctation (spaces between punctures 1–2 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures smaller than or equal to diameter of cells of microreticulation. Pronotum and elytra with distinct punctation, sparser and finer than on head. Pronotum and elytra with strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine sparse punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively short, broad, slightly convex and smooth in the middle, with distinct lateral bead and few lateral setae, lateral sides slightly flattened. Abdominal ventrite 6 slightly truncate.
Male: Antennae simple (Fig.
Female: Unknown.
Exocelina menyamya sp. n. is similar to E. casuarina and E. fume in body size, shape, and coloration but can be distinguished from them by the completely different shape of the median lobe and presence of the pronotal bead.
Papua New Guinea: Morobe Province. The species is known only from the type locality (Fig.
The species is named after Menyamya Village. The name is a noun in the nominative singular standing in apposition.
Copelatus (Papuadytes) messeri
Balke, 1999: 274;
Papuadytes
messeri
(Balke, 1999):
Exocelina
messeri
(
Papua New Guinea: East Sepik Province, Amboin Patrol Post, Karawari Lodge.
Paratypes: 2 males “Papua New Guinea: East Sepik Province, Amboin Patrol Post, Karawari Lodge, 7 Feb.1983, A.C. Messer”, “Paratypus Copelatus messeri Balke des. 1999” [red] (
For complete description, see
See under E. keki sp. n.
Distribution. Papua New Guinea: East Sepik Province. The species is known only from the type locality (Fig.
Papua New Guinea: Eastern Highlands Province, Wapi Creek, Kimiagomo, Okapa, 06°25.41'S, 145°34.48'E, 1900 m a.s.l.
Holotype: male “Papua New Guinea: Eastern Highlands, Wapi Creek, Kimiagomo, Okapa, 1900m, 9.viii.2005, 6 25.407S 145 34.480E, K.Sagata (WB122)” (
3 females “Papua New Guinea: Eastern Highlands, Hano kotu, Kimiagomo, Okapa, 1661m, 11.viii.2006, 06 25.096S 145 34.556E, K.Sagata (WB129)” (
Body size and form: Beetle medium-sized: TL-H 3.95–4.7 mm, TL 4.3–5.05 mm, MW 2.05–2.5 mm (holotype: TL-H 4.3 mm, TL 4.7 mm, MW 2.3 mm), with oblong-oval habitus, slightly more attenuated posteriorly.
Coloration: Piceous, with reddish brown pronotum. Head reddish brown to piceous, paler anteriorly and darker posterior to eyes. Pronotum dark brown to piceous, with reddish to reddish brown sides narrowly or broadly. Elytra dark brown to piceous, sometime with narrow reddish sutural lines. Head appendages and legs proximally yellowish red, legs distally darker, reddish brown, especially metathoracic legs (Fig.
Surface sculpture: Shiny dorsally. Head mostly with fine, sparse punctation (spaces between punctures 2–3 times size of punctures) but punctation denser and coarser between eyes; diameter of punctures smaller than diameter of cells of microreticulation. Pronotum and elytra with very fine, sparse punctation, sometimes inconspicuous on elytra. Pronotum and elytra with weakly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles, abdominal ventrites with distinct microreticulation and strioles. Metaventrite medially, metacoxal plates, and abdominal ventrites with very fine, sparse, often inconspicuous punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, and smooth, with distinct lateral bead and few lateral setae. Abdominal ventrite 6 rounded.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina okapa sp. n. is similar to E. yoginofi sp. n. but differs from it in very weak dorsal punctation and microreticulation and more slender median lobe. The species is also similar to E. mendiensis sp. n. but differs from it in distinctly smaller size and differently shaped apex of the median lobe.
Papua New Guinea: Eastern Highlands Province (Fig.
The species is named after Okapa Station. The name is a noun in the nominative singular standing in apposition.
Exocelina
undescribed sp. MB4921:
Exocelina
piusi
_New_Guinea_MB4921:
Papua New Guinea: East Sepik Province, Lembena, 04°56.859'S, 143°59.375'E, 1,250 m a.s.l.
Holotype: male “Papua New Guinea: East Sepik, Lembena, 335m, 10.ix.2009, 04 56.859S 143 59.375E, Ibalim & Pius (PNG250)”, “M. Balke 4920” (
Body size and form: Beetle small: TL-H 3.5–3.6 mm, TL 3.9–4.0 mm, MW 1.95–2.0 mm (holotype: TL-H 3.6 mm, TL 4 mm, MW 1.95 mm), with oblong-oval habitus.
Coloration: Specimens teneral. Reddish brown, with pronotum slightly paler. Head reddish brown, with small darker areas posterior to eyes. Pronotum yellowish brown, darker on disc. Elytra reddish brown. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. Head with fine, sparse punctation (spaces between punctures 2–3 times size of punctures), only with some larger punctures between eyes; diameter of punctures smaller than diameter of cells of microreticulation. Pronotum and elytra with very fine, sparse punctation. Pronotum and elytra with rather strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine, sparse punctation.
Structures: Pronotum with narrow lateral bead. Its lateral sides with inconspicuous, shallow longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 rounded.
Male: Antennae simple (Fig.
Female: Unknown.
Exocelina piusi sp. n. is similar to E. messeri and, especially, to E. pseudofume sp. n. in body shape, coloration, and dorsal punctation and microreticulation, but differs from them in presence of narrow pronotal bead and shape of the median lobe.
Papua New Guinea: East Sepik Province (Fig.
The species is named for Pius, a local collector. The species name is a noun in the genitive case.
Exocelina
fume
_New_Guinea_MB 4169:
Papua New Guinea: Madang Province, Wannang, 05°15.458'S, 145°02.389'E, 270 m a.s.l.
Holotype: male “Papua New Guinea: Madang, Wannang, 270m 31.x.2008, 05.15.458S 145.02.389E, Posman, (PNG187)” (
Body size and form: Beetle medium-sized: TL-H 3.3–3.6 mm, TL 3.6–3.95 mm, MW 1.8–2.0 mm (holotype: TL-H 3.3 mm, TL 3.6 mm, MW 1.9 mm), with oblong-oval habitus.
Coloration: Reddish to reddish brown, with head and pronotum paler. Head yellowish red to reddish brown, with small darker areas posterior to eyes. Pronotum yellowish red to reddish brown, darker (to brown) on disc. Elytra reddish brown to brown, sometimes with narrow yellowish or reddish sutural lines. Head appendages and legs yellowish red, legs distally darker, especially metathoracic legs (Fig.
Surface sculpture: Shiny dorsally. Head with rather dense punctation (spaces between punctures 1–2 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures smaller than diameter of cells of microreticulation or equal to it. Pronotum and elytra with very distinct punctation, sparser and slightly finer than on head. Pronotum and elytra with weakly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine sparse punctation.
Structures: Pronotum without lateral bead. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 rounded.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina pseudofume sp. n. is similar to E. messeri and E. keki sp. n. but it has distinctly broader and more oval habitus, shinier dorsal surface due to weaker microreticulation, as well as median lobe of different shape: thicker, with apex broader and curved downwards, with visible angle on dorsal side in lateral view. The shape of median lobe is similar to that of E. fume.
Papua New Guinea: Madang (Fig.
The species is named “pseudofume” because shape of its median lobe remains that of E. fume. The name is a noun in the nominative singular standing in apposition.
Papua New Guinea: Simbu Province, Mount Wilhelm, 05°43'15.145"S, 145°16'10.0927"E, 1,200 m a.s.l.
Holotype: male “Ibisca Niugini, PNG 1–3.xi.2012 Mount Wilhelm 1200 m -5,720873833 145,2694702 MW1200 / P1611 Vial 16950” (
Body size and form: Beetle small: TL-H 3.25–3.55 mm, TL 3.65–3.95 mm, MW 1.8–1.85 mm (holotype: TL-H 3.5 mm, TL 3.85 mm, MW 2.0 mm), with oblong to oblong-oval habitus.
Coloration: Reddish brown to dark brown, with head and pronotum paler. Head reddish to reddish brown, with small darker areas posterior to eyes. Pronotum reddish to reddish brown, with dark brown disc. Elytra brown to dark brown, with narrow reddish sutural lines. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. Head with dense, coarse punctation (no spaces between punctures or spaces of equal size of punctures), evidently finer and sparser anteriorly; diameter of punctures equal to or larger than diameter of cells of microreticulation. Pronotum and elytra with dense and coarse punctation, sparser and finer than on head. Pronotum and elytra with rather strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and fine sparse punctation.
Structures: Pronotum with narrow lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 slightly truncate or very slightly concave.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina pseudopusilla sp. n. is similar to E. pusilla sp. n. but larger, more elongate, with denser and coarser dorsal punctation and microreticulation and differently shaped median lobe. See also under E. cyclops sp. n.
Distribution and note on taxonomy. Papua New Guinea: Simbu Province (Fig.
The species was mistaken for E. pusilla sp. n. due to their similarity. The name is a noun in the nominative singular standing in apposition.
Exocelina
undescribed sp. MB1364:
Exocelina
pusilla
_New_Guinea_MB1364:
Papua New Guinea: Madang Province, Akameku-Brahmin, Bismarck Range, 05°47.03'S, 145°24.13'E, 250–500 m a.s.l.
Holotype: male “Papua New Guinea: Madang, Akameku-Brahmin, Bismarck Range, 250–500m, 25.xi.2006, nr 05.47.026S 145.24.131E, Balke & Kinibel (PNG 115)”, “M.Balke 1364” [green] (
Body size and form: Beetle small: TL-H 2.95–3.25 mm, TL 3.2–3.6 mm, MW 1.65–1.85 mm (holotype: TL-H 2.95 mm, TL 3.25 mm, MW 1.65 mm), with oblong-oval habitus.
Coloration: Reddish to reddish brown, with head and pronotum paler. Head yellowish red to reddish, with small darker areas posterior to eyes. Pronotum yellowish red to reddish, with small brownish area on disc. Elytra reddish brown to brown, with narrow reddish sutural lines. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Shiny dorsally. Head with dense, coarse punctation (no spaces between punctures or spaces 2 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures equal to or larger than diameter of cells of microreticulation. Pronotum and elytra with dense and coarse punctation, sparser and finer than on head. Pronotum and elytra with weakly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and fine sparse punctation.
Structures: Pronotum with narrow lateral bead. Its lateral sides with longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 slightly truncate or very slightly concave.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina pusilla sp. n. is very similar to E. cyclops sp. n. in body shape, coloration, and surface sculpture but differs in having distinctly thinner and distally narrowed median lobe. It is also similar to E. adelbertensis sp. n., E. bewani sp. n., and E. sumokedi sp. n. but has coarser dorsal punctation and differently shaped median lobe. See also under E. pseudopusilla sp. n.
Papua New Guinea: Madang and Simbu Provinces (Fig.
The species name derives from the Latin “pusillus” (small, tiny) to express small size of these beetles. The species name is an adjective in the nominative singular.
Papua New Guinea: Simbu/Eastern Highlands Province, Crater Mountain, Sera – Herowana, Sima River, ca 06°06'57.5"S, 145°03'39.4"E, 1,250 m a.s.l.
Holotype: male “Papua New Guinea: Simbu / EHP, Crater Mountain, Sera – Herowana, Sima river, 1250m, 15IX2002, Balke & Sagata, (PNG 016)” (
Body size and form: Beetle small: TL-H 3.6 mm, TL 4.0 mm, MW 2.0 mm, with broader, oval habitus.
Coloration: Reddish brown head and pronotum and piceous elytra. Head reddish in its anterior half and dark brown in posterior one. Pronotum dark brown on disc and gradually paler to yellowish red laterally. Elytra dark brown, paler laterally and almost piceous on disc. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Shiny dorsally. Head with rather dense punctation (spaces between punctures 1–2 times size of punctures) but fine punctation; diameter of punctures smaller than diameter of cells of microreticulation. Pronotum and elytra with distinct punctation, sparser and finer punctation than on head. Pronotum and elytra with weakly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine sparse punctation.
Structures: Pronotum without lateral bead. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, elongate, relatively broad, slightly convex, with distinct lateral bead and few. Abdominal ventrite 6 rounded.
Male: Antennae simple (Fig.
Female: Unknown.
In absence of the pronotal bead and thin and not hook-like anterolateral seta of the male protarsomere 4, Exocelina sima sp. n. is similar to E. keki sp. n., E. messeri, and E. pseudofume sp. n. However, the species distinctly differs from them in more oval body form and more strongly expressed bicolor dorsal surface: reddish head and pronotum and piceous elytra, as well as in a characteristic shape of the median lobe and male abdominal ventrite 6 without lateral striae. The latter character is unique among New Guinea Exocelina.
Papua New Guinea: Simbu and Eastern Highlands Provinces, Crater Mountain. This species is known only from the type locality (Fig.
The species is named after Sima River. The name is a noun in the nominative singular standing in apposition.
Exocelina
undescribed sp. MB3315:
Exocelina
simbaiensis
_New_Guinea_MB3315:
Exocelina
inengensis
MB3309:
Papua New Guinea: Western Highlands Province, Simbai, Ineng River, 05°14.94'S, 144°32.82'E, 2,000 m a.s.l.
Holotype: male “Papua New Guinea: Western Highlands, Simbai, Ineng River, 2000m, 27.ii.2007, 05.14.943S 144.32.818E, Kinibel (PNG 135)” (
Body size and form: Beetle small to medium-sized: TL-H 3.3–4.15 mm, TL 3.65–4.5 mm, MW 1.8–2.15 mm (holotype: TL-H 3.9 mm, TL 4.25 mm, MW 2.0 mm), with rather oblong habitus.
Coloration: Dark brown to piceous, sometimes with reddish pronotum. Head dark brown to piceous, paler anteriorly. Pronotum dark brown to piceous, with reddish brown lateral sides and sometimes anteriorly and narrowly posteriorly. Elytra dark brown to piceous, sometimes with narrow reddish sutural lines. Head appendages and legs proximally yellowish red, legs distally darker, reddish (Fig.
Surface sculpture: Matt dorsally. Head with dense punctation (no spaces between punctures or spaces 2 times size of punctures), finer and sparser anteriorly; diameter of punctures equal to diameter of cells of microreticulation. Pronotum and elytra with slightly sparser and finer punctation than on head. Head, pronotum and elytra with strongly impressed microreticulation. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and fine, sparse but distinct punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 broadly rounded.
Male: Antennomere simple, slightly stout (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Variability. The specimens from Ineng River are larger: TL-H 3.5–4.15 mm; remaining specimens: TL-H 3.3–3.7 mm. In addition, the population from Ineng River shows variability in how strongly apex of the median lobe bent downwards in lateral view.
Exocelina simbaiensis sp. n. is similar to E. yoginofi sp. n. in body form, size, and coloration, but differs from it in distinctly stronger punctation and microreticulation and in thickened apex of the median lobe.
Papua New Guinea: Western Highlands Province, near Simbai (Fig.
The species is named after Simbai area. The name is an adjective in the nominative singular.
Exocelina
undescribed sp. MB3312:
Exocelina
simbaijimi
_New_Guinea_MB3312:
Papua New Guinea: Western Highlands Province, Simbai-Jimi, 05°16.07'S, 144°27.89'E, 1,500 m a.s.l.
Holotype: male “Papua New Guinea: Western Highlands, Simbai - Jimi, 1500m, 2.iii.2007, 05.16.074S 144.27.886E, Kinibel (PNG 140)” (
1 female “Papua New Guinea: Western Highlands, Simbai, 1800–2000m, 25.ii.2007, 05.16.330S 144.33.176E, Kinibel (PNG 133)” (
Body size and form: Beetle medium-sized: TL-H 4.05–5.0 mm, TL 4.4–5.4 mm, MW 2.1–2.55 mm (holotype: TL-H 5.0 mm, TL 5.4 mm, MW 2.5 mm), with oblong-oval habitus.
Coloration: Piceous, with head and pronotum paler. Head dark brown to piceous, reddish brown to brown anteriorly, with small darker areas posterior to eyes. Pronotum reddish brown to brown laterally and piceous on disc. Elytra brown to piceous, sometimes with narrow reddish sutural lines. Head appendages and legs proximally reddish, legs distally darker, brown, especially metathoracic legs (Fig.
Surface sculpture: Submatt dorsally. Head with rather dense, coarse punctation (spaces between punctures 1–2 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures smaller than or equal to diameter of cells of microreticulation. Pronotum with distinct punctation, sparser and finer than on head. Elytra with very fine and sparse punctation. Pronotum and elytra with strongly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and fine, sparse punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, and smooth, with distinct lateral bead and few lateral setae. Abdominal ventrite 6 slightly truncate or broadly rounded.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina simbaijimi sp. n. is similar to E. heidiae in body size and form but differs from it in darker coloration, more distinct dorsal punctation, broader median lobe, with more angulated apex in lateral view and more thickened margins in ventral view.
Papua New Guinea: Western Highlands Province (Fig.
The species is named after Simbai-Jimi area. The name is a noun in the nominative singular standing in apposition.
Papua: Puncak Regency, south from Iratoi, 03°16'48.6"S, 137°20'02.9"E, 150 m a.s.l.
Holotype: male “Indonesia: Papua, S Iratoi, hunting camp, 150m, 28.v.2006, -3,2801742386 137,334125172346, local collectors” (
Body size and form: Beetle small: TL-H 2.7–3.2 mm, TL 3.0–3.55 mm, MW 1.55–1.9 mm (holotype: TL-H 2.95 mm, TL 3.25 mm, MW 1.75 mm), with broader, oval habitus.
Coloration: Brownish, with head and pronotum paler. Head yellowish red to reddish brown in anterior half and brown to dark brown in posterior ones. Pronotum yellowish red to reddish brown on sides, brown to dark brown on disc. Elytra brown to dark brown, with narrow reddish sutural lines. Head appendages yellowish red, legs reddish, distally darker, especially metathoracic legs (Fig.
Surface sculpture: Shiny dorsally. As in E. pusilla sp. n. but punctation finer and sparser and microreticulation weakly impressed.
Structures: Pronotum with lateral bead. Its lateral sides with shallow longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 broadly rounded or slightly truncate.
Male: Antennae simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina sumokedi sp. n. is similar to E. pusilla sp. n. but is smaller, darker, more oval, shinier, with finer and sparser dorsal punctation and weaker microreticulation, with shallow longitudinal impressions on lateral sides of pronotum and different shape of the median lobe. The species is also similar to E. adelbertensis sp. n., E. bewani sp. n., E. cyclops sp. n., and E. pseudopusilla sp. n., see their “Affinities” and “Key”.
Papua: Puncak Regency. The species is known only from the Iratoi area (Fig.
The species is named for our friend Bob Sumoked (Tomohon, Sulawesi). The species name is a noun in the genitive case.
Exocelina
undescribed sp. MB1302:
Exocelina
yoginofi
_New_Guinea_MB1302:
Papua New Guinea: Eastern Highlands Province, Kainantu, Yoginofi, 06°21.80'S, 145°45.46'E, 1,900 m a.s.l.
Holotype: male “Papua New Guinea: Eastern Highlands, Kainantu, Yoginofi, 1900m, 9.v.1994, 06.21.799S 145.45.463E, Balke & Sagata (PNG 55)” (
Body size and form: Beetle medium-sized: TL-H 3.45–4.0 mm, TL 3.85–4.45 mm, MW 1.85–2.15 mm (holotype: TL-H 3.9 mm, TL 4.3 mm, MW 2.0 mm), with oblong-oval habitus.
Coloration: Dark brown to piceous, with paler pronotum. Head reddish to dark brown, paler anteriorly and posteriorly. Pronotum brown to dark brown, with reddish brown lateral sides and sometimes anteriorly and narrowly posteriorly, darker on disc, sometimes to piceous. Elytra brown to piceous, sometimes with narrow reddish sutural lines. Head appendages and legs proximally yellowish red, legs distally darker, reddish brown (Fig.
Surface sculpture: Submatt dorsally. Head with rather dense punctation (spaces between punctures 1–2 times size of punctures), finer and sparser anteriorly; diameter of punctures smaller than or equal to diameter of cells of microreticulation. Pronotum and elytra with sparser and finer punctation than on head. Head, pronotum and elytra with rather strongly impressed microreticulation. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and fine, sparse but distinct punctation.
Structures: Pronotum with distinct lateral bead. Its lateral sides with distinct longitudinal impressions. Base of prosternum and neck of prosternal process with distinct ridge, rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 rounded.
Male: Antennomere simple (Fig.
Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.
Exocelina yoginofi sp. n. is similar to E. simbaiensis sp. n. in body form, size, and coloration, but differs from it in distinctly finer punctation and microreticulation and in having the apex of the median lobe not thickened. Also, see under E. okapa sp. n.
Papua New Guinea: Eastern Highlands Province (Fig.
The species is named after Yoginofi Village. The name is a noun in the nominative singular standing in apposition.
The key is based mostly on the male characters. In many cases, females cannot be assigned to species due to similarity of their external and internal structures (for female genitalia see Figs
1 | Pronotum without lateral bead | 2 |
– | Pronotum with lateral bead | 8 |
2 | Male protarsomere 4 with anterolateral seta hook-like, large, strongly curved | 3 |
– | Male protarsomere 4 with anterolateral seta thin, long, equal or smaller than more laterally situated large setae, slightly curved | 5 |
3 | Median lobe not or slightly narrowed before truncate or slightly concave apex in ventral view (Fig. |
(4) casuarina |
– | Median lobe distinctly narrowed before truncate apex in ventral view (Figs |
4 |
4 | Apex of median lobe curved downwards, with visible angle on dorsal side in lateral view (Fig. |
(7) fume |
– | Apex of median lobe not or only slightly curved downwards in lateral view (Fig. |
(9) ibalimi |
5 | Beetle more oval, broader, with pronotum reddish brown and elytra piceous (Fig. |
(20) sima |
– | Beetle elongate, narrower, with reddish to reddish brown dorsal coloration (Figs |
6 |
6 | Dorsal punctation almost invisible on elytra (Fig. |
(14) messeri |
– | Dorsal punctation distinct on elytra (Figs |
7 |
7 | Dorsal microreticulation more strongly impressed (Fig. |
(10) keki |
– | Dorsal microreticulation less strongly impressed (Fig. |
(17) pseudofume |
8 | Beetle reddish brown, more oval. Usually smaller, TL-H < 3.6 mm | 9 |
– | Beetle reddish brown to piceous, elongate, oblong-oval. Usually larger, TL-H > 4.0 mm; if smaller, see below | 14 |
9 | Beetle larger, TL-H 3.5–3.6 mm, with finer and sparser dorsal punctation and weaker microreticulation. Median lobe as in Fig. |
(16) piusi |
– | Beetle smaller, TL-H 2.7–3.25 mm, usually with distinctly coarser dorsal punctation and sometimes, stronger microreticulation. Median lobe different (e.g., Fig. |
10 |
10 | Median lobe with thinner apex in lateral view, apex narrowed to tip in ventral view (Fig. |
(19) pusilla |
– | Median lobe with apex thickened in lateral view, apex not narrowed to tip, broad, differently truncate in ventral view (e.g., Fig. |
11 |
11 | Median lobe distinctly narrowed distally, with apex roundly truncate in ventral view (Fig. |
(23) sumokedi |
– | Median lobe not or very slightly narrowed distally, with apex distinctly truncate or slightly concave in ventral view (e.g., Fig. |
12 |
12 | Apex of median lobe not curved downwards in lateral view (Fig. |
(5) cyclops |
– | Apex of median lobe curved downwards in lateral view (Figs |
13 |
13 | Apex of median lobe narrower in lateral view and slightly concave in ventral view (Fig. |
(3) bewani |
– | Apex of median lobe broader in lateral view and truncate in ventral view (Fig. |
(1) adelbertensis |
14 | Apex of median lobe strait, flatted, and thin apex in lateral view and broadly elongated, lanceolate, impressed in ventral view (Fig. |
(13) menyamya |
– | Apex of median lobe of different shape, never so flatted and impressed ventrally, usually thickened in lateral view (e.g., Fig. |
15 |
15 | Median lobe evenly broad, with rounded, not curved downwards apex in lateral view (e.g., Fig. |
16 |
– | Median lobe narrowed towards apex, apex pointed or slightly rounded, usually curved downwards in lateral view (e.g., Fig. |
18 |
16 | Beetle smaller, TL-H 3.5–4.3 mm, reddish brown to brown, with distinctly stronger dorsal punctation. Median lobe smaller and thinner (Fig. |
(6) desii |
– | Beetle larger, TL-H 4.05–5.0 mm, dark brown to piceous, with dorsal punctation finer and sparser. Median lobe larger and more robust (Figs |
17 |
17 | Beetle dark brown, with elytral punctation finer. Median lobe thinner and narrower in lateral view (Fig. |
(8) heidiae |
– | Beetle dark brown to piceous, with elytral punctation more distinct. Median lobe thicker and broader in lateral view (Fig. |
(22) simbaijimi |
18 | Beetle more elongate, almost parallel-sided, smaller, TL-H 3.25–4.15 mm, with strong dorsal punctation and microreticulation | 19 |
– | Beetle more oval, larger, TL-H 3.45–5.5 mm, with dorsal punctation and microreticulation in some species much finer and sparser | 20 |
19 | Beetle smaller, TL-H 3.25–3.55 mm, reddish brown to dark brown (Fig. |
(18) pseudopusilla |
– | Beetle larger, TL-H 3.3–4.15 mm, dark brown to piceous (Fig. |
(21) simbaiensis |
20 | Beetle smaller, TL-H 3.45–4.7 mm | 21 |
– | Beetle larger, TL-H 4.8–5.5 mm | 23 |
21 | Apex of median lobe not bent downwards in lateral view, roundly truncate in ventral view (Fig. |
(2) ambua |
– | Apex of median lobe bent downwards in lateral view, rounded in ventral view (e.g., Fig. |
22 |
22 | Beetle smaller, TL-H 3.45–4.0 mm, submatt, with distinct dorsal punctation and microreticulation (Fig. |
(24) yoginofi |
– | Beetle larger, TL-H 3.95–4.7 mm, shiny, with extremely fine, inconspicuous dorsal punctation and weak microreticulation (Fig. |
(15) okapa |
23 | Dorsal punctation and microreticulation weaker (Fig. |
(12) mendiensis |
– | Dorsal punctation and microreticulation stronger (Fig. |
(11) kumulensis |
The studied species have the same habitat preferences as those described in
We are grateful Dr. H. Schillhammer (Vienna) for the habitus photos and Clive R. Turner (Plymouth) for a linguistic review of the manuscript.
Fieldwork was supported by the UK Darwin Initiative project “Training the next generation of PNG conservation biologists” to Aland Stewart, the Wildlife Conservation Society, PNG Program (now PNG Institute for Biological Research), Goroka, EHP, Papua New Guinea, as well as the PNG Binatang Research Center, Madang, Papua New Guinea. Thanks are especially due to Vojtech Novotny, Aloysius Posman, Bangan John, Andrew Kinibel, and Sentiko Ibalim, whose help is greatly appreciated.
The specimens from Mount Wilhelm, Papua New Guinea were collected during the “Our Planet Reviewed Papua-New-Guinea 2012–2013” project. Specimens were exported under the permit # 012297 issued by the Department of Environment and Conservation (DEC, Port Moresby). Sorting and processing of the material was supported by the European Research Council (ERC) grant 669609 to C. Wardhaugh.
Financial support for the study was provided by the FWF (Fonds zur Förderung der wissenschaftlichen Forschung – the Austrian Science Fund) through a project P 24312-B17 to Helena Shaverdo. Michael Balke was supported by the German Science Foundation (DFG BA2152/11-1, 11-2, 19-1, 19-2).