Lacunipotamon, Dai, Song, He, Cao, Xu & Zhong, 1975

Ng, Peter K. L., Tan, Zhi Wan & Ngo, Van Tri, 2023, Fig. 20 in Lanternflies (Hemiptera: Fulgoridae) of Taiwan., Zoological Studies 62 (20), pp. 1-58 : 55-56

Key to species of Lacunipotamon

1a. Epistomal median lobe low, not projecting far beyond level of lateral margins ............................................................................ 2

1b. Epistomal median lobe triangular, produced, projecting well beyond level of lateral margins .................................................. 4

2a. Carapace relatively more rounded; groove between male thoracic sternites 3 and 4 shallow, just visible; G1 terminal segment with distal part strongly recurved; fingers of adult male major chela not gaping ( China) ......................................................................... ............. L. albusorbitum Dai, Song, He, Cao, Xu & Zhong, 1975

2b. Carapace proportionately wider, ovate; groove between male thoracic sternites 3 and 4 distinct; G1 terminal segment with distal part short, gently curved, tip blunt; fingers of adult male major chela gaping ..................................................................... 3

3a. Postorbital crista well developed at lateral edges, with small epibranchial tooth in both sexes; G1 terminal segment with distal part slender, not dilated; in life, carapace white with dark purple ambulatory legs ( Vietnam) ................................... L. panda n. sp.

3b. Postorbital crista not pronounced, without a trace of epibranchial tooth in both sexes; G1 terminal segment with distal part appearing truncate, gently dilating to tip; in life, carapace blue with dirty pale yellow ambulatory legs ( Vietnam) ........................ ........................................................................... L. mimicum n. sp.

4a. Anterolateral margin appears entire, without trace of epibranchial tooth in both sexes; postorbital crista may form raised, rounded angle with lateral margin but not dentiform or tuberculiform .... 5

4b. Anterolateral margin with small epibranchial tooth, may be tuberculiform or visible as sharp angle ...................................... 8

5a. Male anterior thoracic sternum inflated, strongly protruding, forming sharp angle with sternite 5; fingers of adult male major chela strongly gaping; in life, carapace and ambulatory legs greyish-white to white ( Vietnam) ........................ L. pectum n. sp.

5b. Male anterior thoracic sternum not inflated, not protruding, forming rounded surface with sternite 5; in life, colour of carapace and ambulatory legs otherwise .................................... 6 6a. Dorsal lobe of G1 terminal segment asymmetrical with proximal part higher; in life, carapace dirty green to orange ( Vietnam) ...... ......................................................................... L. thuanchau n. sp.

6b. Dorsal lobe of G1 terminal segment forming symmetrical arc; in life, colour of carapace blue to greyish-blue .............................. 7

7a. Suborbital and subhepatic regions with low rugae, pterygostomial regions distinctly rugose; G1 terminal segment with distal part almost straight, not appearing dilated; in life, carapace blue to greyish-blue with light olive-brown ambulatory legs ( China) ...... ..................................... L. cymatile Huang, Shih & Ahyong, 2020

7b. Suborbital, subhepatic and pterygostomial regions smooth; G1 terminal segment with distal part gently upcurved, appearing dilated; in life, carapace blue with brownish-purple to almost black ambulatory legs ( Vietnam) .................. L. sublividum n. sp.

8a. Carapace relatively more rounded; fingers of adult male major chela not gaping; G1 terminal segment with distal part prominently recurved ( Vietnam) .......................... L. globus n. sp.

8b. Carapace proportionately wider, ovate; fingers of adult male major chela gaping; G1 terminal segment with distal part gently curved to almost straight ............................................................ 9

9a. Distal part of G1 terminal segment short, gently upcurved, tip truncate; groove between male thoracic sternite 3 and 4 shallow; fingers of adult male major chela strongly gaping; in life, carapace white with dark purple ambulatory legs ( Vietnam) ........ ....................................................................... L. contrastum n. sp.

9b. Distal part of G1 terminal segment almost straight, conical; groove between male thoracic sternite 3 and 4 deep; fingers of adult male major chela gaping; in life, carapace red with pale orange ambulatory legs or purple with pale yellow ventral colouration ................................................................................ 10

10a. G1 terminal segment with large trapezoidal basal flap, without stumpy dorsal projection; external orbital tooth less strongly produced, broadly triangular; lateral margins of epistomal median lobe almost straight or weakly concave; groove between male thoracic sternite 3 and 4 distinctly anterior to sternopleonal cavity; in life, carapace and ambulatory legs purple ( Vietnam) .... ........................................................................ L. purpureum n. sp.

10b.G1 terminal segment with large round basal flap, with stumpy dorsal projection, directed obliquely anteriorly; external orbital tooth more strongly produced, acutely triangular; lateral margins of epistomal median lobe convex; groove between male thoracic sternite 3 and 4 almost confluent with edge of sternopleonal cavity; in life, carapace red with pale orange ambulatory legs ( China) ......................... L. yuanshi Huang, Shih & Ahyong, 2020