Altica aenea Olivier 1808, stat. rev.
Creators: name: Reid, C. A. M.
name: Beatson, M.
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Chrysomelidae
Altica
Altica aenea

description: Altica aenea (Olivier, 1808) stat. rev.
(Figs 1, 2, 8, 9, 15, 23, 32–34, 47–49, 62–64, 77)
Galeruca aenea Olivier 1808: 646, plate 4, fig. 56 (type locality: Java).
Haltica aenea: Heikertinger & Csiki 1939: 247 (as synonym of A. cyanea sensu auctt.).
Altica aenea: Gressitt & Kimoto 1963: 890 (as synonym of A. cyanea sensu auctt.).
Haltica australis Blackburn 1889: 1493 (type locality: Northern Territory); Weise 1923: 109 (synonym of A. cyanea sensu auctt.).
Altica australis: Gressitt & Kimoto 1963: 890 (as synonym of A. cyanea sensu auctt.); Scherer 1982: 480 (valid species).
Haltica ignea Blackburn 1889: 1494 (type locality: Northern Territory) syn. nov.
Haltica bicolora Jacoby 1904: 182 (type locality: southeast New Guinea) syn. nov.
Altica jussiaeae Gressitt 1955: 34 (type locality: Palau) syn. nov.
Altica caerulea sensu Weise 1923, nec Olivier 1791; Weise 1923: 109.
Altica cyanea sensu auctt. nec Weber, 1801; Maulik 1926: 422.
Altica corrusca sensu auctt. nec Erichson 1842; Bryant & Gressitt 1957.
Material examined (c. 850, * = specimen dissected). Types: Altica aenea (Olivier): Neotype (this designation, see Notes below): ♂/ Java Bogor 26.xii.1964 / J Stusak collector BISHOP/ (BMH); Altica australis (Blackburn): Lectotype (this designation): LH specimen of 2 on card/ N. Territory/ Haltica australis Blackb. cotype/ Haltica australis Bk N.T. cotype 18152/ (SAM); Paralectotypes (4): 1 same data as lectotype, RH specimen on card (SAM); 2[on shared pin]/ N. Territory J.P. Tepper/ Haltica australis Blackb. type / Haltica australis Bk N. Territory type I.3015/ (SAM); 1/ 2514 NT/ Haltica australis Blackb. cotype/ (SAM); Altica ignea (Blackburn): Lectotype (this designation): LH specimen of 2 on card/ TY/ N. Territory J.P. Tepper/ Haltica ignea Blackb. type / Haltica ignea Blackb. N. Territory type I.3017/ (SAM); Paralectotypes (3): 1 same data as lectotype, RH specimen on card (SAM); 2[on card]/ N. Territory/ 2515/ Qu 2515/ Haltica ignea Blackb. cotype/ Haltica ignea Blackb. N. Territory cotype 18153/ (SAM); Altica jussiaeae Gressitt: Paratypes (4): ♂/ Yap I., Yap Gr. Caroline viii.1952 NLH Krauss/ paratype A. jussiaeae / (BMH); ♀/ Yap I, Caroline Is, 28–30.iii.1954 / JW Beardsley collector/ paratype Altica jussiaeae L Gressitt (BMH); ♂*/ Bebelthuap, Ngaremeskang, 25m, 20.xii.1952 / Caroline Is Pac. Sci. Bd. JL Gressitt/ paratype Altica jussiaeae L Gressitt (BMH); ♂/ Peleliu I, north central Pelew Is, viii.1945 / collected by HS Ducoff/ at light/ paratype Altica jussiaeae L Gressitt (BMH).
Non-type material: Australia: Australian Capital Territory: Lake Burley Griffin, feeding on Ludwigia pepaliodes [sic] montevensis (ANIC); 2♂ */ Weston (ANIC); New South Wales: ♂*/ Allyn R, Chichester SF, 32°08S 151°27E (ANIC); Ashfield (AMS); Barrington Tops, i. 1925, SU Zool Exp. (ANIC); Berkshire Park, leaves Jacksonia scoparia (AMS); Bondi (AMS); 1k N Bruinswick Heads (ANIC); Caparra (ANIC); Chiswick, nr Armidale (ANIC); Congo, 35°58S 150°09E (ANIC); Dorrigo (AMS); 26mi NE Grafton (ANIC); Griffith (ANIC); Harrington (ANIC); Kurrajong (AMS); ♂*♀*/ Lansdowne, 31°45S 152°31E (AMS); Lightning Ridge (ANIC); ♂*/ Llandilo, 29.99912S 146.0346E (AMS); Macleay R (ANIC); Maroota, Ludwigia longifolia (ANIC); Moree (AMS, ANIC); Mt Annan Botanic Gardens (AMS); Mullimbimby (AMS); 28k S Narooma, infesting Haloragis exalata (AMS); Sydney (ANIC); Tea Tree Ck (ANIC); Tooloom Plateau, 28°29S 152°24E (ANIC); Tweed R (AMS, ANIC); Upper Kangaroo R nr Yeola, in rotten wood (ANIC); ♂*/ Williamtown, ex Alternanthera filoxeroides (ANIC); Windsor (AMS); Northern Territory: Berrimah (ANIC); ♂*/ 33k SW Borroloola, 16°16S 136°05E (ANIC); 1k NE Cahills Xing, 12°25S 132°58E (ANIC); Cutta Cutta (AMS); Daly R, 13°41S 130°33E, beaten off Mimosa (ANIC); Daly R Mission, 13°31S 138°41E and 13°45S 138°41E (ANIC); Douglas R, 13°45S 131°34E (ANIC); 2♂ */ E Alligator R, 12°26S 132°57E (AMS, ANIC); ♂*/ Ferguson R, 14°48S 131°03E & 19°14S 131°50E (ANIC); Gregory NP, 16°07S 130°26E (ANIC); Holms Jungle (ANIC); Jabiru, 12°41S 132°50E (ANIC); Kakadu NP, 13°35S 132°36E (ANIC); ♂*, Kakadu, S Alligator Resort, 12:40:34S 132:28:41E (AMS, DAD); Keep R NP, 15°45S 129°10E (ANIC); ♂*♀*/ Nourlangie Rock, defoliating Ludwigia (AMS); 18k E Oenpelli, 12°17S 133°13E (ANIC); Port Darwin (AMS); Sixty Mile (ANIC); Virginia, 12:31:19S 131:13:33E, ex Ludwigia (DAD); Yellow Waters, 12°54S 132°31E, Ludwigia (ANIC); Queensland: Archer R, 13°26S 142°29E (AMS, ANIC); 14mi NW Ayr (CAS); Babinda (ANIC, BMH); Bald Mtn via Emu Vale (UQIC); Ban Ban Ra. (ANIC); Banks Id (AMS); Batavia Downs HS, 12°40S 142°40E (ANIC); 23k NE Bauhinia Downs, 24°24S 149°23E (ANIC); Benaraby (ANIC); ♂*/ Bertie Ck Xing, 11°50S 142°30E (ANIC); Biggenden (ANIC); Brisbane (QMB); Broken R, 21°10S 148°30E (AMS); ♂*/ Brookfield (AMS); ♂*/ Bucasia (ANIC); Bundaberg (BMH); Bunya Mtns (QMB); Burnett R, 24°46S 152°25E (ANIC); Burnett R Gorge, Bundaberg (ANIC); Cairns (AMS, ANIC, BMH, QMB, UQIC); 2♂ */ Cardstone (AMS); ♂*/ Carnarvon Gorge NP, 25°3S 148°14E (AMS); Cathedral Fig (ANIC); 15k SW Charleville, 26°32S 146°12E (ANIC); ♀*, Cloncurry (AMS); Cockatoo Ck Xing, 11°39S 142°27E (ANIC); Condamine (AMS); 12mi WNW Cooktown (ANIC); 21k NW Cooktown, 15°25S 145°03E (ANIC); Coorumba (AMS); Crater Lakes NP, SW Biggenden (ANIC); Cunnamulla (AMS); Dallarnil (ANIC); Danbulla FR, 17°10S 145°39E (ANIC); Deeral (BMH); Dunk Id (ANIC); Eidsvold (ANIC); Eubenangee (ANIC); 6k E Kamma (ANIC); Edge Hill, nr Cairns (ANIC); Fanning R, 18°45S 146°27E (AMS); Finch Hatton Gorge, on Ludwigia peploides (ANIC); Garradunga (AMS); Gayndah (AMS); Goondi Hill Swamp (ANIC); Gordonvale (AMS, BMH); 6mi W Gordonvale (CAS); Green Hills (ANIC); Hambledon (BMH); Hann R, 15°14S 144°55E (ANIC); Hell Hole Gorge NP, 25°34S 144°11E (ANIC); 14k NW Hope Vale Mission, 15°16S 144°49E (ANIC); ♂*/ Ingham (ANIC); Innisfail (ANIC); Iron Ra NP, 12°43S 143°18E (AMS, ANIC, UQIC); Joalah NP, 27°56S 153°12E (ANIC); 3k NNE Julatten, 16°35S 145°22E (ANIC); Kowonyama, Mitchell R (ANIC); Kuranda (AMS, UQIC); ♂*/ 2m N Kuranda (ANIC); Lake Barrine, 17°15S 145°38E (ANIC); Lakefield NP, 14°44S 144°07E (ANIC); Langi Lagoon, 13°27S 142°42E (ANIC); Lockerbie, Cape York (UQIC); McIlwraith Ra (AMS); Mer Id (BMH); 21k SE Millaa Millaa (ANIC); Milman, 30k N Rockhampton (ANIC); 3♂ *♀*/ Mission Beach (AMS); Millaa Millaa (AMS); 9k NNW Moonie, 27°39S 150°19E (ANIC); Mt Crosby (AMS); Mt Glorious (ANIC); 10k N Mt Molloy, 16°39S 145°14E (ANIC); ♂*/ Mt Morgan (AMS); Mt Nebo (ANIC); 2k ENE Mt Tozer, 12°44S 143°43E (ANIC); 3k ENE Mt Tozer, 12°44S 143°44E (ANIC); 9k ENE Mt Tozer, 12°43S 143°17E (ANIC); Mourilyan (ANIC); Munduberra (AMS); Mungkan Kandju NP, 13°39S 142°41E (ANIC); Palmerston NP @ 1000’ on Tully Rd (ANIC, UQIC); 32k S Ravenshoe, 17°38S 145°29E (ANIC); Stonehenge, W Qld (UQIC); Tamborine (ANIC); 13k NW Taroom, 25°32S 149°45E (ANIC); Tinarro (ANIC); Tin Ck, Cook Hwy (ANIC); Toowoomba (ANIC); Townsville, reared on Ludwigia (AMS, ANIC); 10k NE Tully, 17°50S 145°59E (AMS); 12k S Tully, 18°02S 145°54E, on Psidium guineense (AMS); Ward R via Charleville (UQIC); ♂*/ West Claudie R (AMS); White Mtns NP, 20°27S 144°49E (ANIC); Yeppoon (ANIC); South Australia: ♂*/ no locality (AMS); Murray R (AMS); Victoria: 3♂ *, ♀*, Barmah NP, 35°53’24”S 145°02’24”E infesting Ludwigia peploides, (AMS), 2♂ */ ditto, aggregating on Eleocharis (AMS); Lake Hattah (ANIC); ♂*/ Shepparton (AMS); Western Australia: ♂*/ Carson Escarpment, 14°49S 126°49E (ANIC); Croosing Falls, Kununurra, defoliating Ludwigia perennis (DAB); Fitzroy R (ANIC); ♂*/ 12k S Kalumburu Mission, 14°25S 126°38E (ANIC; DAB); 14k SE Kalumburu Mission, 14°25S 126°40E (ANIC); 4k W King Cascade, 15°36S 126°15E (ANIC); Kings Sound (ANIC); Kununurra, ex Acacia (DAB); N end Lake Argyle (AMS); ♂*/ Mitchell Plateau, 14°52S 125°50E (ANIC); Wyndham (ANIC); Fiji: ♂*/ Kadavu (AMS); Koronivia, Viti Levu, one specimen labelled “in rice crop” (ANIC, BMH); ♂*/ Ovalau (BMH); Vambea, Ono (BMH); Tamavua, Suva (ANIC); India: ♂*/ Jhansi-Chatarpur (ANIC); Rishikesh (ANIC); Indonesia: Java: Bawean Is (BMH); Bogor (BMH); ♀*/ Buitenzorg (BMH); Kalimantan: Pontianak, Kalimantan Barat (BMH); Maluku: Ambon (BMH); Aru Ids (ANIC); Solea, Seram (AMS); Sulawesi: ♀*/ Palolo, Palu (AMS); Sumatra: ♂*/ Bengkulu (AMS); ♂*/ Kalianda, Ludwigia (AMS); Tanjung Morawa (BMH); Timor: Balical[unknown], Timor Barat (BMH); Naibonat, West Timor, 10°08’S 123°41E (AMS); West Papua: Baliem (BMH): Bokondini (BMH); Enarotadi (BMH); Eramboe (BMH); Guega, W Swart Vy (BMH); ♂*, Kebar Vy, W Manokwari (BMH); Kulima (BMH); Manokwari (BMH); Merauke (BMH); Moanemani, Kamo Vy (BMH); ♂*, Sarmi, W to Hollandia (BMH); ♂*, Sibil Sterrengeb (BMH); ♂*, Tigi Lake (BMH); Wamena (BMH); Malaysia: Bau distr., Sarawak (BMH); Frasers Hill (AMS); Kedah (BMH); ♂*/ Pahang (BMH); Tenompok, Sabah (BMH); 10k SW Tenom, Sabah (BMH); Nepal: ♂*/ Modi Khola R (ANIC); New Caledonia: Bourail (ANIC); La Foa R (AMS); Loyalty Ids, Fayaoue (BMH); Nossirah [Nassiran] (BMH); ♂*/ Yahoue (BMH); Papua New Guinea: Aiyura (BMH); ♂*/ Amboin (ANIC); Baiyer R (BMH); Banz (BMH); Bosavi (ANIC); Brown R (BMH); Bulolo (BMH); Bultemen [unknown], ex sweet potato (AMS); Cape Rodney (BMH); Daragi [Dorogari] (BMH); Daru Id (BMH); Deria, Amazon Bay (ANIC); ♂*, Eliptamin Vy (BMH); Feramin (BMH); Fly R (AMS); Finschafen (BMH); Garaina (BMH); Goroka (BMH); Hargen [unknown] (AMS); Huon Peninsula (BMH); Ihu (AMS); ♂*, Kainantu (BMH); Kerema (BMH); Kiunga, Fly R (BMH); Kokoda (BMH); 2♂ *, Komalabu, New Ireland (AMS); Koroba (BMH); Korgua (BMH); Lae (BMH); ♂*, 11k NW Lae (AMS); ♂*, 19k NE Lae (BMH); Lindenhafen, New Britain (BMH); Lufa (BMH); Madang (BMH); ♂*, 25k SSW Madang (ANIC); Maprik (BMH); Markham R (BMH); Milne Bay (BMH); Moorhead (BMH); Mt Hagen (ANIC); Mt Kaindi (BMH); Mt Kerowagi (BMH); Mt Lamington (AMS); Mt Missim (BMH); ♂*, Murua R (BMH); Musgrave R, Astrolabe (BMH); M’Waka [unknown] (ANIC); Niokamban [unknown], ex snake beans (DAB); ♂*, Nondugl, NE Highlands (BMH); Normanby Id (BMH); Okapa (BMH); Olsobip (BMH); ♂*, Omsis (AMS); Oriomo R (BMH); Oro Bay (BMH); Orokolo (ANIC); Palmer & Black R junction (BMH); Popondetta (BMH); Port Glasgow (BMH); Port Morseby (AMS, BMH); 40k N Port Morseby (AMS); Redscar Bay (BMH); ♂*, Rouku, Morehead R (ANIC); Star Mtns (BMH); Swart Vy (BMH); Telefomin (BMH); 2♂ *, May R, Upper Sepik Distr. (BMH); ♂*, Torricelli Mtns (BMH); ♂*/ Varirata NP (AMS); Wau (ANIC, BMH); Wharton Ra (AMS); Woitape (BMH); 2♂ *, Woodlark Id (BMH); Philippines: Tanay (AMS); Solomon Islands: ♂*/ Bougainville Is (ANIC); 3♂ */ Guadalcanal, Honiara, Ludwigia (AMS); ♂*/ Guadalcanal, Gold Ridge, Ludwigia (AMS); San Cristobal (BMH); Timor Leste: ♂*/ Ira Sequero (AMS); 2♂ */ Los Palos (AMS); Vanuatu: Aneilyum (BMH); Efate (BMH); Espiritu Santo (BMH); ♂*/ Santo (BMH); Vietnam: ♂*/ Bach Ma NP (ROM); ♂*/ 2k S Ngoc Linh (ROM); Sa Pa (ROM).
Description. Length: male 4.6–5.8 mm, female 4.5–6.4 mm.
Colour: dorsum black, usually with dark blue reflection (especially Indomalaya) but east of Timor and in Australia also commonly dark green, coppery-green, dark bronze, purple, or bicoloured (pronotum contrasting with elytra, or elytral suture and margins contrasting with disc), bicoloured form predominant in east New Guinea, Solomons, New Caledonia & Fiji, rarely non-metallic black; venter and legs black with duller reflection, one dissected male from Sepik River, New Guinea, with entirely red legs, one male from Sumatra with asymmetrically coloured red and black tarsi, teneral specimens often with reddish tibiae and tarsi; first antennomere with apical quarter red (dark brown in some NW Victorian specimens) to wholly red, often antennomeres 2–4 also reddishbrown, remainder of antennae black to brown.
15 16 17 18 Head: ratios (Tables 3 & 4): male: EG 3.30–7.00; IE 1.18–1.53; HG 9.00–15.33; HN 1.07–1.18; NE 2.00–2.50; female: EG 3.50–6.83; IE 1.20–1.49; HG 8.70–15.33; HN 1.06–1.19; NE 1.93–2.23; pubescence: a few small setae at inner edge of posterior of orbit, longitudinal row of long setae at sides of frontoclypeal ridge, 2–3 pairs of long setae behind clypeal anterior margin; transverse row of short setae between eye and buccal cavity; face impunctate except minute punctures at bases of setae; vertex with or without microreticulation; postantennal calli smooth, not microsculptured; eyes moderately large and laterally prominent, small-eyed individuals present but infrequent; postantennal calli slightly elongate to transverse, with acute triangular anterior angles and rounded to truncate bases, usually adjacent at base only; frontoclypeal ridge lanceolate, varying from broad and almost flat to narrow and convex, anteriorly terminating in a short keel before clypeal margin; anterior edge of clypeus generally smooth, weakly raised, sides of clypeus microreticulate, slightly rugose.
TABLE 3. Head ratios of male Altica species (1 = 10 specimens; 2 = 5 specimens).
TABLE 4. Head ratios of female Altica species (1 = 10 specimens; 2 = 5 specimens).
Thorax: pronotum evenly convex anteriorly or with pair of shallow depressions behind anterior margin; varying from entirely non-microsculptured to distinctly microreticulate at anterior and basal field and faintly so on disc; non-glandular puncturation variable, from present only as sparse small punctures at basal field, to anterior edge with sparse punctures, basal field with close strigose large punctures (separated by 2–3 diameters) and disc minutely and sparsely punctured (separated by 4–5 diameters at least); hypomeron anteriorly tranversely strigose, without microreticulation; prosternum smooth and shining; elytra shining, without microreticulation, usually strongly and closely but irregularly punctured, interspaces mostly 0.5– 2 x diameters, discal punctures often partly aligned in short rows, sometimes smaller and sparser; elytral laterally smooth behind humeri or weakly keeled to middle; scutellum triangular, microreticulate or shining and smooth; femora densely microsculptured and pubescent; outer face mid tibia with prominent keel for most of length, usually on a convex surface; male first protarsomere distinctly longer than broad, female 1.5–1.7x longer than broad.
Abdomen: abdominal ventrites densely microsculptured and pubescent; male: penis 1.65–1.95mm long; in dorsal view almost entirely parallel-sided to the rounded apex, which has a short projecting truncate lobe; almost straight in lateral view, with tip (truncate lobe) kinked, least so in some New Guinea specimens; shallowly transversely ridged on middle of dorsal surface (ridges effaced in two dissected males from New Ireland); venter without transverse or oblique ridges, two short apicoventral depressions present, 0.2–0.25x penis length, ovate, smooth surfaced and laterally smooth edged, separated by a broad flat ridge; female: tignum 0.85–0.95mm long; tignum with narrow acutely tipped base, narrower than base of apical part, long lateral arms, elongately triangular to threadlike, and broad triangular or spatulate apex; spermathecal collum of variable length and thickness and containing 1–3 twists.
Distribution and biology. Altica aenea is widespread in tropical Australia, but generally near-coastal, from north Western Australia (Derby) to the east coast, then south to Shepparton, Victoria, and as far west as the southern Murray River, South Australia. Outside Australia, A. aenea is found from India and Nepal east through southeast Asia to the west Pacific Islands of Palau, Fiji, New Caledonia and Vanuatu. In New Guinea and southeast Asia this species occurs from sea level to 2000 m.
Based on label data of the specimens examined, Altica aenea primarily feeds on Ludwigia species throughout its range. A short description of the biology of A. corrusca in north Queensland (Hawkeswood 1988), noting that it occurred widely on Ludwigia, is almost certainly based on A. aenea, but may also include A. caerulea. Published records of A. corrusca from the Pacific are misidentifications of A. aenea and all record it on Ludwigia (Bryant & Gressitt 1957; Samuelson 1973). The record of A. gravida on Ludwigia in Fiji (Veitch & Greenwood 1921), assigned to A. corrusca by Bryant & Gressitt (1957), must also be A. aenea, as only this species of Altica occurs on Fiji (Bryant & Gressitt 1957; BMH; pers. obs., CAMR). However, Vestjens’ (1979) study of the biology of A. ignea was a misidentification of A. gravida (q.v.). The description and illustration of immature stages of A. cyanea from Taiwan (Takizawa 1978; Lee & Cheng 2007) is based on a blue species of Altica feeding on Ludwigia, almost certainly A. aenea.
The most frequently recorded host species is Ludwigia peploides, a significant weed in the USA (Harms & Grodowitz 2012) as well as in Asian rice fields. Altica aenea (as A. cyanea) has been proposed as a biological control agent of Ludwigia species in ricefields (Dubey 1981; Nayek & Banerjee 1987; Xiao-Shui 1990). These authors note that larvae are predated by pentatomid bugs. The A. foveicollis proposed as a biocontrol agent of Ludwigia in Bangladesh and Thailand (Alam & Karim 1980; Napompeth 1991) is probably also a misidentification of A. aenea.
Rarely, A. aenea may feed on other hosts. Two specimens were collected on Citrus (Rutaceae) in Australia causing “medium damage to leaves” (Kakadu National Park, June 2007, coll. S Anderson). There are no other regional records of Altica species on citrus (Jolivet 1991) but two North American species of Altica are recorded from this host (Clark et al. 2004). There are also specimens of A. aenea from Fiji labelled “growing leaf tips of rice” (BPBM), however we suspect that the label refers to non-feeding specimens or is a mislabelled sweep of rice with Ludwigia present. Nayek & Banerjee (1987) tested A. aenea on rice and found that it failed to feed. Other plant associations from label data are singletons, probably representing casual, non-feeding, occurences or visits to non-host nectaries, or mislabelling: Alternanthera (Amaranthaceae) Jacksonia, Mimosa, Vigna (Fabaceae), Psidium (Myrtaceae).
In Australia Altica aenea has been collected in every month of the year, without a strong seasonal pattern. It is commonly collected at light.
Taxonomic notes. Altica aenea was feebly described and illustrated by Olivier (1808) based on material from Java: having size and shape of A. caerulea but distinguished by being bronze-green with brown first antennomere. Olivier described it in Galeruca Geoffroy, 1762, not Haltica or Altica (Gruev & Döberl 1997, 2005). In the last 100 years this species has been consistently treated as a junior synonym of A. cyanea, which was a misidentification (q.v.). Altica aenea becomes the oldest available name for the commonest and most widespread Altica species throughout the region, with A. australis (Blackburn, 1889) or A. ignea (Blackburn, 1889) as the next oldest names. No type material has been found in the two locations where it is likely to exist, MHNP & NMSE. The combination of absence of type material and poor original description makes use of the name A. aenea problematic. However, as A. aenea has consistently been treated as a junior synonym of A. cyanea s. auctt., we think it is worth keeping the name A. aenea for this species by fixing its identity with a neotype. The neotype chosen is from the type locality, Java, with the key feature, the reddish-brown first antennomere.
Gruev & Döberl (1997) listed A. aenea as one of eight synonyms of A. cyanea. Altica birmanensis is valid (q.v.). Altica janthina is correctly placed as a junior synonym of A. cyanea (q.v.). Altica brevicosta is a junior synonym of A. caerulea (q.v.). The remaining names are discussed below.
Altica australis (Blackburn, 1889), was described from the Northern Territory and compared only with a single European species. Weise (1923), followed by Heikertinger & Csiki (1939), placed it in synonymy with his concept of A. cyanea, which was misidentified as a senior synonym of A. aenea. However, Scherer (1982) seems to have considered A. australis a valid species. We have examined type material (in SAM) and concur with the synonymy of A. australis with A. aenea.
Altica ignea (Blackburn, 1889), was also described from the Northern Territory and was compared with A. australis, differing by presence of a lateral elytral ridge and coppery colour. However the type material (SAM) shows that this is also an example of A. aenea (syn. nov.), with the short lateral elytral ridge that occasionally occurs in this species.
Altica bicolora (Jacoby, 1904) comb. nov. was described from New Guinea as a possible colour variety of A. pagana (= A. corrusca, see above). Jacoby noted it was distinguished by the contrast between bluish pronotum and greenish elytra, impunctate pronotum and semiregular puncturation of the elytra. He described the penis as “long and slender, its apex rounded, with a small dent at the middle, the surface with the margins surrounding the orifice, thickened, the latter itself feebly ridged at the middle” (Jacoby 1904: 482). This is a reasonable description of how the penis of A. aenea differs from that of A. corrusca, and also distinguishes it from A. caerulea, the other bicoloured species in New Guinea The other features he noted are either within the range of variation of A. cyanea (colour, elytral sculpture) or misleadingly described (Jacoby overlooked the ‘punctures’, really glandular openings, present near the anterior margins of all Altica species). In collections available to us there are specimens of Altica from New Guinea and the Solomon Islands with the same colours and general morphology as described for A. bicolora. These specimens were collected on Ludwigia, the host of A. aenea. We have dissected male and female specimens from these samples and all belong to A. aenea as defined here. Altica aenea is therefore a subjective senior synonym of A. bicolora (syn. nov.).
The last synonym of A. aenea listed by Gruev & Döberl (1997), Altica nepalensis Chujo, 1966, was placed in synonymy with A. cyanea by Kimoto & Takizawa (1973), but their A. cyanea is evidently a composite of A. aenea, A. birmanensis and A. cyanea. Without type material we cannot determine the correct synonymy of this species name, but our studies of collections show that A. aenea certainly occurs in Nepal.
Altica jussiaeae was described as a distinct species from the west pacific islands of Palau and Micronesia (Gressitt 1955), less than 900 kilometres north of New Guinea. Morphologically it falls well within the range of A. aenea and it shares the same host plant (Ludwigia). The four type specimens of A. jussiaeae examined are unusually coloured for A. aenea, black with faint bronze metallic hue and with antennomeres 2–4 reddish, but this colour pattern is found in A. aenea specimens from elsewhere. The male and female genitalia are identical to those of A. aenea, which we therefore make a subjective senior synonym of A. jussiaeae (syn. nov.).
Altica foveicollis (Jacoby, 1889), described from northeastern India, was synonymised with A. aenea (as A. cyanea), as a colour variety, by Kimoto (2000; Döberl 2010a). However, photographs of a syntype in the Jacoby collection (Perkins et al. 2010) show that A. foveicollis is densely microsculptured, with costate and finely punctured elytra. Furthermore, if the male genitalia of A. foveicollis illustrated by Scherer (1969: 130) belong to correctly identified material, this appears to be a species distinct from A. aenea. Therefore we conclude that Altica foveicollis is unlikely to be a synonym of A. aenea. Naples & Kessler (2005) report different host species of Ludwigia for A. aenea (as A. cyanea) and A. foveicollis, which may be significant.
Another potential synonym of A. aenea is A. subaurichalcea (Weise, 1922b), described from specimens collected at light on the Mekong Delta, Vietnam, and therefore likely to be a common species in the region. Weise’s description is poor (1922b: 156), but he noted that the penis is almost identical (“täuschend ähnlich”) to that of ‘ A. cyanea ’ (probably referring to A. aenea). We have seen material of both A. aenea and A. cyanea from south Vietnam, plus specimens of a small golden-green species with similar penis to A. aenea (in ROM). Altica subaurichalcea was synonymised with A. birmanensis by Kimoto (2000; as A. subaurantica [sic]) and Döberl (2010a), synonymised with A. coerulea by Gruev & Döberl (2005), and ignored by Medvedev (2009) in his review of Vietnamese alticines. Based on the material we have examined and the original description, A. subaurichalcea is either a synonym of A. aenea or a valid species, but it is not a synonym of A. birmanensis or A. caerulea.
Two males from New Britain (Papua New Guinea) have the dorsal transverse ridges of the penis effaced, but otherwise show typical morphological features of A. aenea. Females associated with these specimens have genitalic characteristics typical of A. aenea. Rather than erect a new species for this population, we consider it to be a variant within the species A. aenea.
Specimens of Altica aenea, A. birmanensis, A. corrusca and A. cyanea are only reliably separated by careful examination of the genitalia but the host plants and ranges provide useful diagnostic information. In southeast Asia, A. corrusca is absent and the other three species appear to have different preferred hosts: A. aenea on Onagraceae (Ludwigia), A. cyanea on Melastomaceae (Melastoma) and A. birmanensis on Polygonaceae (Polygonum).
description: Published as part of Reid, C. A. M. & Beatson, M., 2015, Disentangling a taxonomic nightmare: a revision of the Australian, Indomalayan and Pacific species of Altica Geoffroy, 1762 (Coleoptera: Chrysomelidae: Galerucinae), pp. 503-551 in Zootaxa 3918 (4) on pages 513-524, DOI: 10.11646/zootaxa.3918.4.3, http://zenodo.org/record/245277