Palaechthina Brinck, 1948, 2013

Morrone, Juan J., 2013, The subtribes and genera of the tribe Listroderini (Coleoptera, Curculionidae, Cyclominae): Phylogenetic analysis with systematic and biogeographical accounts, ZooKeys 273, pp. 15-71 : 26

publication ID

https://dx.doi.org/10.3897/zookeys.273.4116

persistent identifier

https://treatment.plazi.org/id/52A95056-8738-93A5-BC46-DA4AEE8D14C0

treatment provided by

ZooKeys by Pensoft

scientific name

Palaechthina Brinck, 1948
status

stat. n.

Subtribe Palaechthina Brinck, 1948 stat. n.

Palaechtini Brinck, 1948:

43; Bouchard et al. 2011: 603 (incorrect original stem formation, not in prevailing usage).

Type genus.

Palaechthus C. O. Waterhouse, 1884 (by original designation, as Palaechtus , incorrect subsequent spelling).

Diagnosis.

Rostrum slender, as long as or longer than pronotum (except for some species of Listronotus where the rostrum is shorter than pronotum); scrobes long, deep, sharply bordered, reaching eyes; scape usually short (not reaching anterior margin of eye when resting in scrobe); pronotum usually subclyndrical or subcircular; elytra oblong-oval to elongate-oval.

Biology.

Most of the species of Palaechthina are associated to aquatic or semiaquatic plants, being found in wet or damp conditions ( May 1970; O’Brien 1977, 1981; Marvaldi 1994; Morrone and O’Brien 2000). In contrast with the remaining Listroderini , larvae usually lead a more endophytic way of life inside the stems of several aquatic plants (Oberprieler, in press).

Included taxa.

This subtribe includes the genera Anorthorhinus , Gunodes , Haversiella , Inaccodes , Listronotus , Neopachytychius , Palaechthus , Palaechtodes , Steriphus and Tristanodes . Anorthorhinus and Steriphus are Australian; Gunodes , Inaccodes , Palaechthus , Palaechtodes and Tristanodes are distributed in the Tristan da Cunha-Gough islands; and the remaining three genera are found in the Americas: Haversiella and Neopachytychius in South America and Listronotus has a disjunct distribution in South and North America.

Key to the genera of Palaechthina

1 Funicular segment 1 subequal to or shorter than 2 2
- Funicular segment 1 longer than 2 6
2 Elytra with intervals convex; North and South America Listronotus ( Fig. 21 View Figures 18–26 )
- Elytra with intervals flat; Tristan da Cunha-Gough islands 3
3 Small to very small (3.7-6.5 mm) Tristanodes
- Medium-sized to large (7.0-12.0 mm) 4
4 Vestiture of subcircular scales and setae; pronotum subcircular; elytra oblong-oval Gunodes
- Vestiture of seta-like scales and setae; pronotum subtrapezoidal or subclyndrical; elytra elongate-oval 5
5 Large (11.0-12.0 mm); rostral dorsal carinae absent; pronotum subtrapezoidal Palaechthus
- Medium-sized (7.0-7.5 mm); rostral dorsal carinae present; pronotum subclyndrical Palaechtodes
6 Scape long (surpassing posterior margin of eye when resting in scrobe); elytra with anteapical tubercle Steriphus
- Scape short (not reaching anterior margin of eye when resting in scrobe); elytra lacking anteapical tubercle 7
7 Vestiture of seta-like scales and setae; Australia and Tristan da Cunha-Gough islands 8
- Vestiture of subcircular scales ans setae; South America 9
8 Funicular segments 3-6 elongate; club fusiform; pronotum subclyndrical; elytra with intervals convex; Australia Anorthorhinus
- Funicular segments 3-6 globose; club inflated; pronotum subcircular; elytra with intervals flat; Tristan da Cunha-Gough islands Inaccodes
9 Vestiture of subcircular scales and setae; rostral dorsal carinae present; mandibles long and narrow; antennal insertion distal; postocular lobes slightly developed; elytra oblong-oval; tibiae with spurs Neopachytychius ( Fig. 22 View Figures 18–26 )
- Vestiture of subcircular scales only; rostral dorsal carinae absent; mandibles robust; antennal insertion at the middle of the rostrum; postocular lobes absent; elytra elongate-oval; tibiae lacking spurs Haversiella ( Fig. 20 View Figures 18–26 )

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Curculionidae