Platyplectrus Ferrière

Zhu, C. D. & Huang, D. W., 2004, A study of Platyplectrus Ferrière (Hymenoptera: Eulophidae) in mainland China, Journal of Natural History 38 (17), pp. 2183-2209 : 2186-2192

Genus Platyplectrus Ferrière

Platyplectrus Ferrière, 1941: 20 . Type species: Platyplectrus natadae (Ferrière) .

Autoplectrus Gadd, 1945: 336 . Type species: Autoplectrus taprobanes Gadd ; by monotypy. Synonymized by Bouček, 1988: 634.

Diagnosis. Propodeum not areolate, with one strong median carina ( figures 5, 21, 32); scutellum with sublateral grooves straight, or curved inwards subbasally, or curved inwards to meet with each other posteriorly ( figures 5, 20, 31, 32, 42, 43, 60, 62, 64, 68); hind with two tibial spurs, with at least one longer than basitarsomere in most cases ( figure 10); notauli distinct, reaching scutoscutellar suture ( figures 5, 20, 31, 43).

Remarks. Bouček (1988) listed Trichoplectrus as another synonym of Platyplectrus , but for the reasons given above, we treat it as a synonym of Metaplectrus . Anelli present in all studied species of Platyplectrus from China, but it is absent in one Sri Lankan species ( Wijesekara and Schauff, 1994).

Study of Chinese Platyplectrus revealed several external morphological features useful for distinguishing between the species, genera of Euplectrini , and between the tribes Euplectrini and Elachertini. At the species level, the following differentiating features appear stable and easy to use: (1) occiput rounded off ( figures 3, 27, 50, 53, 56, 63) or distinctly margined with a transverse carina ( figures 55, 57, 59, 61, 65); (2) post-occipital carina present ( figures 3, 14) or absent ( figures 27, 39); (3) pronotum rounded off into neck ( figures 6, 20, 33, 44, 68) or with distinct transverse carina ( figures 6, 49, 54); (4) scutellum smooth ( figures 5, 31, 43) or sculptured ( figure 21); (5) scutellum with sublateral grooves straight till the posterior end ( figure 5) or posteriorly curved inwards to meet medially ( figures 20, 31, 32, 42, 43, 60, 62, 64, 68); (6) sublateral grooves on scutellum narrow ( figures 5, 31, 32, 43, 62, 64, 68) or broad ( figures 20, 21, 60); and (7) petiole elongate ( figures 8, 9, 47) or transverse

( figure 24), or even not apparent. There are also some other features that differ between species, but which require very careful examination with a high-quality light microscope or scanning electron microscope (SEM). For example, sublateral grooves on scutellum maybe smooth or sculptured at bottom ( figure 21). At the

generic level, differential features include: (1) lateral flaps present at mouth corners of Platyplectrus ( figures 2, 15, 26, 38), Aroplectrus and Euplectrus , but absent from studied Euplectromorpha (see Zhu and Huang, 2000: figure 9); (2) ventral plaque present at inner margins of antennal scape of some males of Platyplectrus ( figure 18) and many males of Euplectrus (see Gonzalez, 1984). Features from both the lateral and ventral parts of the mesosoma, especially the carinae on the ventral parts of propodeum ( figures 7, 23, 34, 35, 45, 46), support a closer relationship of Euplectrini with Elachertini than to Eulophini and Ophelimini ( Zhu and Huang, 2001). Besides, there are some other features which have proved to be useful in recent comparative morphological study (unpublished data), but these characters have to be observed from the posterior part of head ( figures 3, 4, 14, 27, 28, 39), lateral part of body ( figures 6, 33, 44) or ventral part of body ( figures 7, 8, 22, 23, 34, 35, 46). Thus, with sufficient materials, we pulled the head and the legs apart from the body and treated each part for SEM observations. As we did SEM observations on only parts of the studied species, we did not include these

morphological characters in the diagnosis or description of each species. However, we include them in the plates for future comparisons.

Recent examination of Platyplectrus from all over the world demonstrates considerable variation in structure of the sublateral grooves on scutellum. In some instances, when the scutellum is strongly rugose, rugulose or reticulate, there is no delimitation between the grooves and the area lateral to the grooves. However, the area between the paired scutellar setae always differs from the area lateral to the setae in Platyplectrus , unlike in Euplectrus . For this reason, we transfer Euplectrus bussyi to Platyplectrus .

Distribution. All except for Neotropical regions.