Key to Myrmecina of China

This key to workers of Myrmecina from China is based on Zhou et al. (2008) and the key to Southeast Asian species by Okido et al. (2020) as modified by Liu et al. (2022).

1

Antennae with 11 segments. China (Hunan) => Myrmecina pauca

Antennae with 12 segments => 2

2

Lateral portions of clypeus raised into a sharp ridge or shield wall in front of the antennal insertions (Figure 1A, B) => 3
Lateral portions of clypeus not raised into a sharp ridge or shield wall in front of the antennal insertions (Figure 1C, D) => 4

Fig. 1. Head in full-face view. (A) Myrmecina guangxiensis (CASENT0070290), (B) M. wilsoni (MCZENT00763515), (C) M. pierceae (MCZ-ENT00759962), (D) M. gaoligongensis (MCZ-ENT00759990). (Liu et al. 2022, Fig. 1)

3

return to couplet #2

Postpetiole expanded laterally, more than 2 times broader than petiole => Myrmecina eowilsoni

Fig. 3. M. eowilsoni (MCZ-ENT00763515). (A) Body in profile view. (B) Body in dorsal view. (C) Head in fullface view. (D) Distribution map in SE Asia. (Liu et al. 2022, Fig. 3)

Postpetiole not expanded laterally, slightly broader than petiole => Myrmecina guangxiensis

4

return to couplet #2

Propodeal spines not straight in dorsal view (Figure 2B, C) => 5
Propodeal spines straight, not curved outwards at the apex in dorsal view (Figure 2A) => 6

5

return to couplet #4

Propodeal spines distinctly curved outwards at the apex in dorsal view (Figure 2B) => Myrmecina curvispina

Propodeal spines with small hooks at their apex (Figure 2C) => Myrmecina hamula

Fig. 2. Propodeal spines in dorsal view. (A) M. pierceae (MCZ-ENT00759962), (B) M. curvispina (MCZENT00863515), (C) M. hamula (MCZ-ENT00863516). (Liu et al. 2022, Fig. 2)

6

return to couplet #4

First gastral tergum with dense punctation => Myrmecina raviwonghei

Myrmecina raviwonghei (CASENT0713298). (A) Body in profile view. (B) Body in dorsal view. (C) Head in full-face view. (D) Distribution map. (Liu et al. 2022, Fig. 6)

First gastral tergum smooth and shiny => 7

7

return to couplet #6

Ventrolateral portion of head with punctures, without longitudinal rugae => 8
Ventrolateral portion of head with only longitudinal rugae, or smooth and shiny => 9

8

return to couplet #7

Head in full-face view with dense punctation, and clearly visible longitudinal rugae medially. Anterior margin of clypeus weakly concave to almost straight => Myrmecina gaoligongensis

Fig. 4. M. gaoligongensis (MCZ-ENT00759990). (A) Body in profile view. (B) Body in dorsal view. (C) Head in full-face view. (D) Distribution map in SE Asia. (Liu et al. 2022, Fig. 4)

Head in full-face view with dense punctation, without longitudinal rugae medially, but with weak irregular rugae laterally. Anterior margin of clypeus strongly concave with three distinct processes => Myrmecina asthena

9

return to couplet #7

Anterior clypeal margin without median process => 10
Anterior clypeal margin with median process => 12

10

return to couplet #9

Eye small, comprising less than 10 ommatidia (7-8); body yellowish orange or yellow => Myrmecina taiwana

Eye moderately large, with more than 10 ommatidia, body dark brown or black => 11

11

return to couplet #10

Ventrolateral portion of head sculptured with longitudinally rugose => Myrmecina sinensis

Ventrolateral portion of head smooth and shiny => Myrmecina sauteri

12

return to couplet #9

Eye large and oval, comprising more than 20 ommatidia => Myrmecina striata

Eye small and circle, comprising 10 ommatidia or less => 13

13

return to couplet #12

Head in full-face view sculptured with longitudinal rugae posteriorly curving towards occipital corners, ventrolateral portion of head smooth and shiny => Myrmecina pierceae

Fig. 5. M. pierceae (MCZ-ENT00759962). (A) Body in profile view. (B) Body in dorsal view. (C) Head in fullface view. (D) Distribution map in SE Asia. (Liu et al. 2022, Fig. 5)

Head in full-face view with straight to weakly oblique longitudinal rugae not curving towards the occipital corners, ventrolateral portion of head with longitudinal rugae => Myrmecina asiatica

References