Dudgeodes Sartori, 2008

Sartori, Michel, Peters, Janice G. & Hubbard, Michael D., 2008, A revision of Oriental Teloganodidae (Insecta, Ephemeroptera, Ephemerelloidea), Zootaxa 1957 (1), pp. 1-51 : 25

Dudgeodes Sartori gen. nov

Type species: Dudgeodes pescadori Sartori sp. nov. by present designation

= Teloganodes sensu Ulmer and subsequent authors, nec Eaton, 1882

( hutanis + stephani + pescadori + celebensis + ulmeri )

Description. Adult: forewing long and slender, posterior margin regularly convex ( Figs. 9, 11 ). Pterostigmatic area with 7–10 crossveins reaching subcostal vein; vein MP 2 short and free or long and attached to CuA and MP 1, cubital field with 1– 4 intercalary veins. Hind wing small with costal process acute; 3 longitudinal veins well developed ( Figs. 10, 12 ). Claws of all legs dissimilar, one obtuse, the other hooked. In male foreleg, length of tibia ca. 1.8 length of tarsus. Styliger plate slightly concave medially. Male gonopods ( Fig. 13 ) threesegmented; first segment subequal in length to second and third combined; third much reduced. Penis lobes completely fused, except at apex, elongated but shorter than gonopods ( Fig. 13 ). Subanal plate of female slightly rounded. Gill socket vestiges visible on segments II–V. Terminal filament absent.

Nymph ( Figs. 132, 135 , 138, 141 , 144 ): Body flattened, eyes in dorsal position blackish or yellowish in male nymphs; head capsule with hair like setae on lateral margins ending in front of eyes. Labrum covered with numerous long and simple setae ( Fig. 22 ). Forefemora broad and dilated with a transverse row of setae on dorsal face (Figs. 65, 67, 69 71 73). Gills on abdominal segments II–V (Figs. 91–94); gills II–IV with ventral lobes, gill V without; gills III–V incised. Abdominal carina (median tubercles on terga) well or poorly developed. Posterolateral expansions poorly or well developed. Lateral margins of terga with long and thin setae. Terminal filament absent.

Egg: ovoid, chorion lacking attachment structures, one polar cap with epithema; a row of polygonal chorionic structures close to the epithema ( Figs. 103–114 ).

Etymology. The new genus is an arbitrary combination of letters to honour Prof. David Dudgeon ( Hong

Kong University) for his outstanding contributions to the ecology of Oriental aquatic macroinvertebrates,

especially mayflies; followed by the suffix – odes to remember its relationship with Teloganodes . The gen-

der is masculine.

Diagnosis. The genus Dudgeodes is easily distinguished from Teloganodes by the following characters: in the adult stage, outer margin of forewing regularly convex, hindwing smaller with acute costal process, tarsi of male foreleg shorter than in the previous genus, styliger plate not strongly convex; in the larval stage, by the absence of gill VI and last gill always incised (entire in Teloganodes ), by the shape of the incisor of the right mandible and by the single seta on the ventral face of the galea-lacinia (except multiple in D. ulmeri ).

Species included:

Dudgeodes hutanis Sartori sp. nov. (Borneo)

Dudgeodes lugens ( Navás, 1933) comb. nov. ( China)

Dudgeodes stephani Sartori sp. nov. (Borneo)

Dudgeodes ulmeri Sartori sp. nov. (Java, Sumatra)

Dudgeodes pescadori Sartori sp. nov. ( Philippines)

Dudgeodes celebensis Sartori sp. nov. (Sulawesi)

Distribution. From South China, throughout Southeast Asia up to Sulawesi (Australasian Realm) FIGURES 65–76. Forefemur (65, 67, 69, 71, 73, 75) and setae on the transverse row (66, 68, 70, 72, 74, 76) of Dudgeodes spp. and Derlethina eloisae . Insertion of the setae on the margins indicated by dots; only some setae drawn. Figs. 65–66: D. hutanis ; Figs. 67–68: D. stephani ; Figs. 69–70: D. ulmeri ; Figs. 71–72: D. pescadori ; Figs. 73–74: D. celebensis ; Figs. 75–76: D. eloisae . Femora at same scale; setae at same scale.

Figures

FIGURE 9–13. Dudgeodes spp. Fig. 9: Female subimago forewing of Dudgeodes hutanis; Fig. 10: Hindwing of D. hutanis; Fig. 11: Male imago forewing of Dudgeodes pescadori; Fig. 12: Hindwing of D. pescadori; Fig. 13: Genitalia in ventral view of D. pescadori.

FIGURES 132–137. Holotypes of Dudgeodes spp. in dorsal view (132, 135), abdomen in ventral view (133, 136) and in lateral view (134, 137). Figs. 132–134: D. hutanis; Figs. 135–137: D. pescadori

FIGURES 138–143. Holotypes of Dudgeodes spp. in dorsal view (138, 141), abdomen in ventral view (139, 142) and in lateral view (140, 143). Figs. 138–140: D. ulmeri; Figs. 141–143: D. stephani

FIGURES 144–149. Holotypes of Dudgeodes and Derlethina in dorsal view (144, 147), abdomen in ventral view (145, 148) and in lateral view (146, 149). Figs. 144–146: Dudgeodes celebensis; Figs. 147–149: Derlethina eloisae

FIGURES 16–25. Labrum (16, 18, 20, 22, 24), with details of the dorsal setae (17, 19, 21, 23, 25), of Oriental Teloganodidae. Insertion of the setae indicated by dots on the labrum. Figs. 16–17: Teloganodes tuberculatus; Figs. 18–19: T. hubbardi; Figs. 20–21: T. jacobusi; Figs. 22–23: Dudgeodes hutanis; Figs. 24–25: Derlethina eloisae. All labra at same scale and all setae at same scale, two times enlarged compared to the labra.

FIGURES 103–108. Egg structure of Dudgeodes hutanis (SEM pictures). Fig. 103: Shape of the egg; Fig. 104: Detail of the polar cap; Fig. 105: Detail of the lateral attachments with coiled threads; Fig. 106: Detail of the chorion; Fig. 107: Micropyle area; Fig. 108: Detail of the structure located opposite to the polar cap.

FIGURES 109–114. Egg structure of Dudgeodes pescadori (SEM pictures). Fig. 109: Shape of the egg; Fig. 110: Detail of the polar cap; Fig. 111: Detail of the collar with threads of the epithema; Fig. 112: Detail of the chorion; Fig. 113: Detail of the lateral attachments; Fig. 114: Micropyle area.