Leiodytes surianiae, Hendrich & Wang & Balke, 2021

Hendrich, Lars, Wang, Liang-Jong & Balke, Michael, 2021, Taxonomic revision of Australasian diving beetles in the genus Leiodytes Guignot 1936 (Coleoptera: Dytiscidae, Bidessini), Zootaxa 4990 (1), pp. 23-44 : 29-33

Leiodytes surianiae sp. nov.

( Figs 1C , 2B , 3B , 6 , 9A , 10 , 12B )

Type locality. Northern Queensland, Port Douglas .

Type material. Holotype, male. “ AUSTRALIA Qld Port Douglas Jan 8, 1991 D. Larson ”, “ Holotype, Leiodytes surianiae sp. nov. Hendrich, Wang & Balke des. 2021” [red printed label] ( ANIC).

Paratypes (20 specimens). 2 exs., “N QLD, Cape Tribulation Road S of ferry station, forest swamp, 12m, 15.IX.2006, 16.17.469S 145.19.122 E, L. & E. Hendrich leg. (QLD 35)” ( ZSM) ; 3 exs., “ AUSTRALIA Qld Port Douglas Jan 8, 1991 D. Larson ” ( ANIC) ; 8 exs., “ AUSTRALIA Qld 15 km N Cairns Jan 11, 1991 D. J. Larson ” ( ANIC, CLH, ZSM) ; 7 exs., “ Papua New Guinea , Central, Moreguina [10° 0’S, 148°28’E], 18.viii 2008, Posman ( PNG 184)”, “ M. Balke 3795” [green printed label] ( ZSM) . All paratypes are provided with our red printed paratype labels .

Description of male. Externally characterized by a slightly elongated body, dense elytral punctation and almost testaceous to pale ferruginous body without darker markings on elytra. Dorsoventrally more flattened. Cervical line present.

Measurements. Holotype: TL = 1.9 mm, TL-H = 1.7 mm; breadth = 0.95 mm. Paratypes: TL = 1.75–1.9 mm, TL-H = 1.55–1.7 mm; breadth 0.9–0.95 mm.

Head. Ferruginous, rather shiny, with scattered small punctures. Microreticulation clearly visible. Punctures weakly anteriorly and strongly posteriorly between eyes. Cervical line indistinct and fine but present ( Fig. 3B ). Antennae ferruginous, antennomeres 2–10 almost as wide as long.

Pronotum. Ferruginous, posterior margin with narrow darker marking, broadest at posterior corners. Punctation of varying size, widely and evenly distributed, shiny and microsculpture absent. Sides of pronotum margined and almost evenly rounded. Basal pronotal plicae present. Striae well defined, almost 1/2 length of pronotum, strongly incurved.

Elytra. Ferruginous, without any markings ( Fig. 1C ). Coarsely and densely punctate, shiny, microsculpture absent. Striae strongly impressed, same length as basal pronotal striae but straighter. Elytron simple, without a well-marked ridge.

Ventral surface. Ferruginous. Metacoxae and metaventrite covered with numerous quite strong punctures, surface shiny, without microreticulation. Abdominal ventrites 1 and 3 with few shallow punctures, shiny, microreticulation absent. Metacoxal lines raised, subparallel, well separated. Epipleuron testaceous, with few coarse punctures, shiny, lacking microsculpture, and without transverse epipleural carina at humeral angle ( Fig. 2B ). Legs completely ferruginous.

Male. Median lobe of aedeagus as in Figs 6A, B . In ventral view asymmetrical, very broad and rounded at apex ( Fig. 6A ). Paramere bi-segmented as in Fig. 6C .

Etymology. Dedicated to Suriani Surbakti (Cenderawasih University UNCEN, Waena, Papua), who organized a field trip for an UNCEN team to southern New Guinea (Wasur Reserve), where part of the material treated here in this paper was collected. This work is part of a bilateral training and education project between UNCEN and ZSM (see Surbakti et al. 2021). The specific epithet is a substantive in the genitive case.

Differential diagnosis. The species is near to P. wattsi sp. nov. but can be distinguished by the head having a fine and indistinct cervical line, the elytra without any markings, the smaller size ( Fig. 1C ), and by the shape of the median lobe of aedeagus ( Figs 6A, B ) and paramere ( Fig. 6C ).

Collecting notes. In Queensland (Loc. 35) the species has been collected in small, shallow puddles, rich in decaying leaves, in a half-shaded palm tree swamp not far from the coast ( Fig. 12B ). At this locality L. surianiae sp. nov. was syntopic with L. wattsi sp. nov. and L. migrator .

Distribution. South-eastern part of Papua New Guinea and north-eastern Queensland ( Fig. 9A ).

Figures

FIGURE 1. Body outline and colour pattern of: (A) L. migrator from North Queensland, near Cardwell; (B) L. migrator from Ubirr Rock, Kakadu NP, Northern Territory; (C) L. surianiae sp. nov.; (D) L. wattsi sp. nov. (Scale bar = 1 mm)

FIGURE 2. Ventral surface of: (A) L. migrator; (B) L. surianiae sp. nov.; (C) L. wattsi sp. nov. (Scale bar = 1 mm)

FIGURE 3. Dorsal surface of head of: (A) L. migrator; (B) L. surianiae sp. nov.; (C) L. wattsi sp. nov. (Scale bar = 0.5 mm)

FIGURE 6. Leiodytes surianiae sp. nov.: Median lobe of aedeagus: (A) ventral view, (B) lateral view; right paramere (inner surface): (C) lateral view. (Scale bar = 0.15 mm)

FIGURE 9. Distribution of L. surianiae sp. nov. (A) and L. wattsi sp. nov. (B).

FIGURE 10. Maximum likelihood tree for Australasian Leiodytes. Neighbour joining tree (p-distances) calculated with Geneious (11.0.4.) software. The stars mark those specimens distributed over two divergent clades of L. migrator, which, however, occur syntopically.

FIGURE 12. (A) Creek at Manton Dam, Northern Territory (NT 1), habitat of L. wattsi sp. nov. and L. migrator; (B) Queensland, Forest swamp near Cape Tribulation Road, south of Daintree ferry station (QLD 35), habitat of L. surianiae sp. nov., L. wattsi sp. nov. and L. migrator (B).