Meleagros Kirschenhofer, 1999

Fedorenko, D. N., 2020, New species of Meleagros and Tarsagonum (Coleoptera: Carabidae: Platynini) from the Oriental region, Russian Entomological Journal 29 (2), pp. 139-147 : 140-141

Meleagros Kirschenhofer, 1999

Kirschenhofer, 1999: 68; Morvan, 2004: 3; 2006: 97. — Colpodes : Andrewes, 1923: 683 (part.); Louwerens, 1953: 79 (part.).

Type species: M. coeruleus Kirschenhofer, 1999 .

DIAGNOSIS. Macropterous platynine carabids of medium size (BL ca. 10–14 mm); dorsum metallic, violaceous blue; body integuments microscopically setulose to nearly glabrous. Head with a deep neck constriction and one, posterior, supra-ocular seta before the level of posterior margin of eye; eyes small and protruding, genae long, coarsely cross-striated ventrally and laterally. Antennae pubescent from segment 4 onward, scape and pedicel unisetose; antennomere 3 with no setae other than verticellate ones. Right mandible with two large teeth in apical half. Submentum quadrisetose, mentum tooth largely bifid, setae distant. Prosternal process beaded or not, inclination x-shaped. Pronotal and elytral setation complete. Abdominal sternite VII with 1 (♂) or 2 (♀) setae on each side. Tarsi wide and flat, tri- or tetracarinate dorsally, with long and very dense yellow ventral vestitute; tarsomeres 1–4 with LAS, metatarsomere 4 lacking LAS, tarsomeres 1–3 with DAS, tarsomere 4 strongly bilobed, anterior lobe longer than posterior, more so in metatarsi; tarsomere 5 glabrous ventrally. Metacoxa bisetose (inner seta missing); setation of pro- and metafemur nearly groundplan for Platynini : profemur with one anterior seta, medioventral, and three posterior setae, basal, medioventral, and apical (medioventral setae ranging slightly in number between species as well as between specimens of one species); metafemur mostly with one or two anteroventral setae. Basal two protarsomeres biserially squamose on ventral side in male. Protibiae anteriorly more or less distinctly micropunctate. Female gonosubcoxite IX with a row of several setae along apical margin, gonocoxite IX with one dorsal seta and 4–5 ventral (lateral) ensiform setae. Aedeagus as for Platynini , internal sac unarmed.

Besides species described below, the genus includes the following four species: M. sikkimensis ( Andrewes, 1923) from the Himalayas; M. coeruleus Kirschenhofer, 1999 (Pahang, Malay Peninsula); M. burmanensis Morvan, 2004 ( Burma); and M. sinicola Morvan, 2006 (Yunnan, China).

GEOGRAPHIC DISTRIBUTION. Northeastern India, Nepal, Bhutan, Myanmar, Malay Peninsula, southern China, Vietnam.

HABITATS AND HABITS. There are no exact data published except that the adults of M. coeruleus have been collected at 1400–1800 m elevation [ Kirschenhofer, 1999]. All the adults of the species described below were taken in montane monsoon forests at 1200–2100 m altitudes. That of M. astericollis sp.n. was taken by pitfall trap and those of M. laticeps sp.n. also by pitfall traps near a fallen tree. The other specimens were hand collected, including a male specimen of M. pseudosinicola sp.n. taken sitting on a Zingiberacea plant leaf in the daytime. These data, combined with macropterous condition of the adults and such morphological adaptations as well-developed prominent eyes and a very dense ventral pubescence of the tarsi, argue in favor of phytophilous, most likely arboricolous, way of life.

COMMENTS. Within Oriental Platynini , Meleagros is distinctive chiefly in the combination of a plesiomorphic character, apically rather a wide, rounded to nearly bifid, mentum tooth, and a few surely apomorphic characters, including peculiar mandibles, one supra-ocular seta, and ventral pad spanning but two (vs. three, as usual in Platynini ) basal protarsomeres in male. The genus otherwise matches well the lineage formulated by Habu [1978] as the “ Loxocrepis subgenusgroup of the genus Agonum Bonelli, 1810 ” largely corresponding to the genus Loxocrepis Eschscholtz, 1829 sensu lato. Bousquet [2003] recognized also Hikosanoagonum Habu, 1954 as a separate genus, while treating the other members of the lineage as the subgenera of Agonum (sensu lato), among them Gyrochaetostilus Habu, 1978; Lissagonum Habu, 1978 ; Dicranoncoides Habu, 1978 ; Nymphagonum Habu, 1978 ; Celaenagonum Habu, 1978 , and Achaetoprothorax Habu, 1978 . Schmidt [2017] considered the taxa listed and Takasagoagonum Habu, 1977 as separate genera.

The lineage is defined chiefly by tarsal characters, metatarsomere 4 narrow or very narrow, with outer apical lobe considerably or much longer than inner one and at least outer (anterior) LAS missing. Other distinctive features are as follows: tarsi dorsally bisulcate and mostly carinate between the sulci; setation of the elytra and usually also of the head and pronotum complete (this pattern includes clypeal seta and two supra-ocular setae on each side; pronotum quadrisetose; elytron with parascutellar seta, three discal seta in interval 3, two preapical setae in interval 7, and apical sutural seta); antennae and abdomen without additional setae; abdominal sternite VII with one (♂) or two (♀) setae on each side; profemur mostly with 2–3 posterior medioventral setae; metacoxa mostly trisetose. Many representatives of the genus are macropterous, resulting in metaventrite fairly long, including metepisterna considerably longer than wide and often also elytra mucronate.

Provisionally, I consider those taxa of the lineage that share simple mentum tooth as subgenera or species groups of Loxocrepis , among them Celaenagonum , Takasagoagonum, Gyrochaetostilus , Lissagonum , Dicranoncoides , Nymphagonum , Achaetoprothorax , and Nesiocolpodes Jeannel, 1948 . Dicranoncus Chaudoir, 1850 appears to be another subgenus of Loxocrepis , too. These taxa are more or less well delimited when a local fauna is considered [ Habu, 1978], but on larger geographic scale the limits between them tend to become increasingly obscure as more species are brought into comparison. No significant character but conspicuously mucronate elytra differentiate Violagonum violaceum (Chaudoir, 1859) , the nominotypical species of the genus, from the members of Loxocrepis (s.str.), which invites new synonymy, Loxocrepis Eschscholtz, 1829 = Violagonum Darlington, 1956 , syn.n.

Within the lineage, a more or less bifid mentum tooth is observed in Hikosanoagonum and Meleagros only. The two genera share also a short ventral pubescence of the body and wide tarsi, which character combination may suggest closer relationships between them than between either and the other representatives of the lineage in question. Taken separately each or combined, some other features of Meleagros are found also in a few (sub)genera of Loxocrepis . Specifically, Dicranoncus, Gyrochaetostilus , Lissagonum , and Dicranoncoides share multiple (4–7) ventral ensiform setae in the female gonocoxite IX; at least some species of Dicranoncoides , Nymphagonum and Celaenagonum have developed small and prominent eyes and usually also long genae; and Nesiocolpodes has the tarsi quite similar in shape and setation.

Morvan [2004] revised Meleagros and keyed its four species, including an unnamed species from China, he described later [ Morvan, 2006] as M. sinicola . He also re-described M. coeruleus and M. sikkimensis ( Andrewes, 1923) and reported the latter from Katmandu, Nepal, in addition to previously known records of M. sikkimensis in India and Bhutan. Two earlier records of this species,´Pahang´ and´Burma´ [ Louwerens, 1953] are likely to refer to M. coeruleus and M. burmanensis Morvan, 2004 , respectively.Because the two species are very similar in body shape, including rather narrow pronota and larger (longer) eyes (HnW/OL ca. 1.9), they seem to be more related to each other than to the congeners.

In describing M. burmanensis, Morvan distinguished it from M. coeruleus by the proximal mandibular tooth absent from (vs. present on) the right mandible, combined with the body more narrow and the pronotum larger, or broader, as indicated in the key. This disagrees with his Figures 2–3 and 13–14 [ Morvan, 2004] showing the elytra shorter and the pronotum slenderer in M. burmanensis than in M. coeruleus, EL /EW 1.52 vs. 1.62 and PW/PL 1.07 vs. 1.20, respectively. These inconsistency and the fact that I have not seen these species, makes me key them below based on their descriptions and re-descriptions, including illustrations, compared.

Figures

Figs 1–3. Dorsal habitus of holotypes: 1 — Meleagros laticeps sp.n.; 2 — M. pseudosinicola sp.n.; 3 –– M. setulosus sp.n. Рис. 1–3. Габитус голотипов, дорЗально: 1 — Meleagros laticeps sp.n.; 2 — M. pseudosinicola sp.n.; 3 –– M. setulosus sp.n.

Figs 7–16. Median lobe of aedeagus in holotypes: 7, 9 — Meleagros laticeps sp.n.; 8, 10 — M. pseudosinicola sp.n.; 11–13 — Tarsagonum (Louwerensium) breve sp.n.; 14–16 — T. (L.) indicum sp.n.; 7, 8, 11, 15 — left aspect; 9–10, 13–14 — ventral aspect; 12, 16 — right aspect. Scale bars: 0.5 mm. Рис. 7–16. СреднЯЯ долЯ Эдеагуса голотипов: 7, 9 — Meleagros laticeps sp.n.; 8, 10 — M. pseudosinicola sp.n.; 11–13 — Tarsagonum (Louwerensium) breve sp.n.; 14–16 — T. (L.) indicum sp.n.; 7, 8, 11, 15 — слева; 9–10, 13–14 — вентрально; 12, 16 — справа. Масштаб: 0,5 mm.