Three new species of the extant genus Eucinetus from mid-Cretaceous amber of northern Myanmar (Coleoptera: Eucinetidae)
Author
Li, Yan-Da
0000-0002-9439-202X
State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China & Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol BS 8 1 TQ, UK
ydli@pku.edu.cn
Author
Engel, Michael S.
0000-0003-3067-077X
Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024 - 5192, USA & Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Lima 15081, Perú & Departamento de Entomología, Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima 15072, Perú
mengel@amnh.org
Author
Huang, Di-Ying
0000-0002-5637-4867
State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China
dyhuang@nigpas.ac.cn
Author
Cai, Chen-Yang
0000-0002-9283-8323
State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China
cycai@nigpas.ac.cn
text
Zootaxa
2024
2024-08-05
5492
2
214
230
http://zoobank.org/880aec67-7542-4e96-98cd-86a2c2a31da3
journal article
10.11646/zootaxa.5492.2.4
1175-5326
13219234
880AEC67-7542-4E96-98CD-86A2C2A31DA3
Eucinetus panghongae
Li & Cai
sp. nov.
(
Figs 5–8
)
Material.
Holotype
,
NIGP203940
, male.
Etymology.
The species is named after the coleopterist Dr. Hong Pang.
Locality and horizon.
Amber mine located near Noije Bum Village, Tanai Township, Myitkyina District,
Kachin State
,
Myanmar
; unnamed horizon, mid-Cretaceous, Upper Albian to Lower Cenomanian.
Diagnosis.
Labrum emarginate (
Fig. 7A
). Apical maxillary palpomere asymmetrical, apically with aciculate tip (
Fig. 7A
). Antennomere 3 about 0.85 times as long as 4 (
Fig. 7A
); antennomere 11 about 2.5 times as long as wide (
Fig. 7B
). Scutellar shield rounded at apex (
Fig. 7F
). Elytra about 1.8 times as long as combined width. Hind wings present. Metanepisternum at least twice as long as wide. Meso- and metatibiae at most with only one or two spines along outer edge (
Figs 6B
,
7E
). Mesotibial spurs large; both distinctly stouter than spines along apical fringe of mesotibia (
Fig. 7D
). Metatibial spurs equal (
Fig. 7F
).
FIGURE 5.
General habitus of
Eucinetus panghongae
Li & Cai
sp. nov.
, holotype, NIGP203940, under incident light.
A
, Dorsal view.
B
, Ventral view. Scale bars: 500 μm.
FIGURE 6.
General habitus of
Eucinetus panghongae
Li & Cai
sp. nov.
, holotype, NIGP203940, under confocal microscopy.
A
, Dorsal view.
B
, Ventral view. Scale bars: 500 μm.
Description.
Body fusiform and slender, about
1.6 mm
long,
0.7 mm
wide; surface with fine short setae.
Head deflexed against ventral side of prothorax; entirely concealed from above by pronotum. Compound eyes weakly emarginate anteriorly, with interfacetal setae. Antennae 11-segmented, filiform; antennomere 2 elongate; antennomeres 3–10 moderately longer than wide; antennomere 3 about 0.85 times as long as 4; antennomere 11 about 2.5 times as long as wide. Frontoclypeal suture straight anteriorly and with distinct anterolateral angles. Labrum weakly narrowed toward apex, apically emarginate. Mouthparts non-suctorial. Apical maxillary palpomere asymmetrical, apically with aciculate tip.
Prothorax widest at base. Lateral pronotal carinae complete, simple. Pronotal disc simple. Procoxae obliquely oriented, well-projecting, narrowly separated. Scutellar shield rounded at apex. Elytra about 1.8 times as long as combined width; transversely strigulate; sutural stria present; epipleuron narrow, incomplete. Hind wings present. Metaventral posterior process with distinct median discrimen. Metanepisternum at least twice as long as wide. Metacoxae contiguous; metacoxal plates well-developed and greatly enlarged.
FIGURE 7.
Details of
Eucinetus panghongae
Li & Cai
sp. nov.
, holotype, NIGP203940, under confocal microscopy.
A
, Head, dorsal view.
B
, Antennae.
C
, Mid leg.
D
, Fore and mid legs.
E
, Mid leg.
F
, Abdominal apex, ventral view.
G
, Hind leg.
H
, Scutellar shield, dorsal view.
I
, Abdominal apex, dorsal view.Abbreviations: a2–11, antennomeres 2–11; cl, clypeus; lb, labrum; mstb, mesotibia; mttb, metatibia; mtts, metatarsus; mtv, metaventrite; mxp, maxillary palp; pts, protarsus; sc, scutellar shield; v5–6, ventrites 5–6. Scale bars: 100 μm.
Mid and hind legs with fringe of spines at apices of tibiae and tarsomeres; fore legs without apical fringes of spines. Meso- and metatibiae at most with only one or two spines along outer edge. Mesotibial spurs large; both distinctly stouter than spines along apical fringe of mesotibia. Metatibial spurs equal. Tarsi 5-5-5, simple. Meso- and metapretarsal claws with accessory lobes (
Fig. 7G
).
Abdomen with six ventrites. Posterior margin of ventrite 5 subtruncate, not emarginate.
Remarks.
The sternite VIII of NIGP203940 (and also NIGP203939) is densely covered with setae like the preceding ventrites (
Fig. 7F
). It should be normally exposed when alive, representing the sixth ventrite. In some recent comprehensive coleopteran compendia, the abdomen is described as having only five ventrites for the whole
Eucinetidae
(
Lawrence & Ślipiński 2013
;
Leschen 2016
). However, the sternite VIII is actually commonly exposed in many extant members of
Eucinetus
(
Vit 1977a
)
.