Lamelligomphus Fraser 1922

Wilson, Keith Duncan Peter & Xu, Zaifu, 2009, Gomphidae of Guangdong & Hong Kong, China (Odonata: Anisoptera) 2177, Zootaxa 2177, pp. 1-62 : 34-36

Key to Chinese Lamelligomphus Fraser 1922

Figs. 14 (a–f), 15(a–n), 16(a–t), 17(a–z)

Lamelligomphus parvulus Zhou and Li (2000) , described from Yunnan, is here considered a junior synonym of Lamelligomphus laetus Yang and Davies 1993 . Zhou & Li (2000), when describing L. parvulus , compared it only with Lamelligomphus formosanus and overlooked the existance of Lamelligomphus laetus , also described from Yunnan, which has the same colour pattern and structure of both caudal and secondary genitalia.

1 Labrum predominantly yellow, finely bordered with black ( Figs. 16g & 16j)............................................................. 2

- Labrum black with yellow or greenish oval spots at each side ( Fig. 14a)................................................................... 5

2 Yellow synthoracic dorsal stripe very broad, dominating the dorsum ( Fig. 16h); yellow transverse stripe across crest of frons complete; subgenital plate v-shaped (male unknown) ( Figs. 16g –i); Shaanxi .................................................. ............................................................................................................................ L. hanzhongensis Yang and Zhu 2001

- Yellow synthoracic dorsal stripe narrow....................................................................................................................... 3

3. Tranverse yellow crest on postfrons divided; female occiput black with yellow spot and pair of narrowly separated, short horns ( Figs. 16j–l) (note male unknown); Yunnan. ................................................................ L. chaoi Zhu 1999

- Transverse yellow crest stripe very broad, covering anterior three-quarters of postfrons and extending to cover upper half antefrons................................................................................................................................................................. 4

4. Anterior hamulus with posterior branch hooked and anterior branch wanting; tip of posterior hamulus pointed and slightly curved; female occiput with pair of slightly curved and divaricate horns, widely separated at base; subgenital plate v-shaped ( Figs. 17n–r). Note: female labrum and some male labra, including type, are predominantly yellow but according to Klots (1947) male labrum may also be black with large yellow quadrate spots (see also couplet 14); China (Fujian, Hebei, Jilin, Shanxi, Sichuan) & Korea...................................................... L. ringens ( Needham 1930)

- Semicircular prominences above lateral ocelli present; hamuli as in L. ringens above and not like L. choui s. str. which has markely hooked posterior hamulus (female L. choui tienfuensis unknown). Sichuan. ................................. ..................................................................................................................................... L. choui tienfuensis Chao 1995

5. Dorsal carina of synthorax broadly yellow and joined to yellow collar stripe; female occiput with short horns, narrowly separated at base ( Figs. 17k–m - male unknown); Jiangxi ............................................... L. trinus ( Navás 1936)

- Dorsal carina of synthorax black or narrowly yellow (when viewed dorsally) and usually not linked to collar stripe. ...................................................................................................................................................................................... 6

6. Basal half of male abdominal S8 with pair of very large hump-like, anteriorly-pointed tubercles; anterior hamulus with posterior branch long, hooked at apex and anterior branch short and thumb-like; posterior hamulus straight and pointed; female occiput with pair of divaricate horns narrowly separated at base; subgenital plate u-shaped ( Figs. 17f–j); Vietnam, China (Fujian, Guangdong, Guangxi, Hainan).......................................... L. camelus ( Martin 1904)

- Basal half of abdominal segment 8 without large prominences; female occipital horn and subgenital plate not as above ............................................................................................................................................................................. 7

7. Antehumeral stripe complete; posterior branch of anterior hamulus wanting and posterior hamulus distinctly hooked at tip; tip of superior appendage blunt and boat-shaped when viewed laterally; female unknown ( Figs. 14a–f); Anhui ................................................................................................................................. L. choui choui Chao and Liu 1989

- Male hamules and superior appendages not as above or if similar (as in L. tutulus ) antehumeral stripe present as superior spot and separate stripe; female without almost conjoined occipital horns as above or if these are present (as in L. formosanus ) occiput with marked depressions at sides and top of frons with deep central groove..................... 8

8. Metepisternum black with prominent and complete yellow stripe or yellow central stripe narrowly linked to superior yellow spot and extending to spiracle ( Fig. 16m). Anterior hamulus divaricate, with short posterior branch, acutely curved apically and short anterior branch parallel to tip of posterior branch; posteror hamulus curved at tip; female with short occipital horns, broad at base and not separated; v-shaped subgenital plate ( Figs 16m –t); Yunnan ............. .................................... L. laetus Yang and Davies 1993 …(= Lamelligomphus parvulus Zhou and Li 2000 syn. nov.)

- Metepisternum predominantly black with 2 nd yellow stripe reduced to small isolated superior spot (below wing base) or small superior spot in addition to isolated central stripe ( Fig. 16c); – note some specimens (e.g. L. formosanus ) may possess central stripe narrowly linked to superior spot but if this feature present then stripe does not usually extend to spiracle Fig. 15b)........................................................................................................................................... 9

9. Antehumeral stripe present ......................................................................................................................................... 10

- Antehumeral stripe absent or reduced to small superior spot ..................................................................................... 12

10. Anterior hamulus with posterior branch long, hooked at apex and anterior branch short and thumb-like; inner fold at tip of inferior appendage visible when viewed laterally; distal edge of S8 markedly raised above level of S9; male yellow crest stripe confined to postfrons; female occipital margin with pair of prominent horns, adjacent at base, and nearly parallel-sided but slightly divaricate distal halves; occiput with narrow central hump below horns with slight depression at sides; v-shaped subgenital plate ( Figs. 15a–n); Fujian, Guangdong, Guangxi, Guizhou & Taiwan........ ............................................... L. formosanus ( Matsumura 1926) . (= Lamelligomphus jiuquensis Liu 1993 syn. nov.)

- Anterior hamulus with posterior branch hooked and anterior branch wanting; female with occiput and occipital horns not as above....................................................................................................................................................... 11

11. Posterior hamulus hooked at tip; female occiput with pair of horns which are very wide at their basal half; u-shaped subgenital plate ( Figs. 17a–e); Guangxi, Guizhou ............................................... L. tutulus Liu & Chao in Chao 1990

- Posterior hamulus pointed and straight at tip; female occiput with pair of triangular-shaped horns, broad at base and narrowly divided; v-shaped subgenital plate ( L. hainanensis only occasionally with antehumeral stripe ( Figs. 16a–f & also couplet 13); Hainan, Hong Kong................................................................ L. hainanensis ( Chao 1954) in part

12. Male occiput with pronouced central tubercle; anterior hamule with posterior branch straight rather than hooked at tip; female occiput also with tubercle; subgenital plate u-shaped ( Figs. 17u–z); Xizang ... L. motuoensis ( Chao 1983)

- Male occiput without pronounced central tubercle; anterior hamule with posterior branch hooked at tip; female occiput also without tubercle ...................................................................................................................................... 13

13. Transverse yellow crest stripe across postfrons not as extensive as below and divided centrally; female occiput with pair of narrowly divided horns, broad at base; v-shaped subgenital plate ( Figs. 16a–f & also couplet 11); Hainan, Hong Kong.............................................................................................................. L. hainanensis ( Chao 1954) in part

- Transverse yellow crest stripe very broad, covering three quarters of the postfrons and extending to cover upper half of antfrons ................................................................................................................................................................... 14

14. Anterior hamulus with posterior branch hooked and anterior branch wanting; tip of posterior hamulus pointed and slightly curved; female with pair of slightly curved and divaricate horns, widely separated at base; subgenital plate v-shaped ( Figs. 17n–r and see also couplet 4); Korea, China (Fujian, Hebei, Jilin, Shanxi, Sichuan) .......................... ........................................................................................................................................... L. ringens ( Needham 1930) .

- Presence of semi-circular prominences above lateral ocelli; hamuli as ringens above and not like L. choui s. str. which has markely hooked posterior hamulus (female L. choui tienfuensis unknown); Sichuan .................................. ..................................................................................................................................... L. choui tienfuensis Chao 1995