Derlethina eloisae 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 : 45-47

Derlethina eloisae Sartori sp. nov.

( Figs. 14, 15 , 24, 25 , 32 , 39 , 58 , 75, 76, 81, 95–97, 115–119, 147–149)

Material examined. Holotype: 1 male nymph, Indonesia, East Kalimantan, Malinau Basin, Seturan (old growth forest) – Seturan , 3°00'05''N, 116°30'48''E, 28.III.2001, P. Derleth & B. Feldmeyer (B1313) [ MZL] Paratypes: 12 nymphs, same data as holotype [5 in FAMU, remaining in MZL]; 92 nymphs, Seturan (2000- petak 43) - Temalat (Sungai Guang), trib. Seturan, 2°59'29''N, 116°33'29''E, 16.IV.2001, P. Derleth (B0813) [5 in each LIPI, ZMH, AMG, remaining in MZL]; 32 nymphs, same locality but 18.VI.2000, P. Derleth & J.L. Gattolliat (B0811) [of which 2 partially mounted on microscopic slide]; 11 nymphs, same locality but 14.VIII.2000, P. Derleth & R. Schlaepfer (B0812) [of which 2 partially mounted on microscopic slide]; 2 nymphs, Langap Sud (1995) - Ngayo, trib. Rian, 3°04'56''N, 116°30'58''E, 13.VII.2000, P. Derleth (B0431) [of which 1 partially mounted on microscopic slide]; 3 nymphs, same locality but 14.IV.2001, P. Derleth & M. Sartori (B0433); 5 nymphs, Seturan (2001-petak 57) - Tamalang, trib. Seturan, 2°59'22''N, 116°30'29''E, 18.VII.2000, P. Derleth & F. Béboux (B0511); 9 nymphs, same locality but 10.IV.2001, P. Derleth (B0513); 6 nymphs, Seturan (2001-petak 57) - Tamalang, trib. Seturan, 2°59'22''N, 116°30'46''E, 08.VIII.2000, P. Derleth (B0531); 9 nymphs, same locality but 11.IV.2001, P. Derleth & B. Feldmeyer (B0533); 1 female imago, Seturan (2000-petak 44-45) - Wok (Sungai Guang), trib. Seturan, 2°59'12''N, 116°33'11''E, 05.IV.2001, P. Derleth & B. Feldmeyer (B0713); 23 nymphs, Seturan (2000-petak 43) - Temalat (Sungai Guang), trib. Seturan, 2°59'29''N, 116°33'29''E, 16.IV.2001, P. Derleth & M. Sartori (B0833); 1 nymph, Seturan (unlogged forest) – Seturan, 2°58'54''N, 116°33'29''E, 24.IV.2001, P. Derleth & M. Sartori (B1413); 6 nymphs, Seturan (unlogged forest) – Seturan, 2°58'58''N, 116°33'30''E, 26.IV.2001, P. Derleth (B1423) [ MZL] .

Other material: 1 nymph, Indonesia - East Kalimantan - Malinau - Langap Sud (1997-petak 6) - Belakau, trib. Rian, 3°04'04''N, 116°30'26''E, 20.IV.2001, P. Derleth & M. Sartori (B0113); 3 nymphs, same locality but 05.VII.2000, P. Derleth (B0111); 1 nymph, same locality but 13.VI.2000, P. Derleth (B0110); 2 nymphs, Langap Sud (1997-petak 6) - Belakau, trib. Rian, 3°04'04''N, 116°30'26''E, 18.IV.2001, P. Derleth & M. Sartori (B0123); 3 nymphs, same locality but 07.VII.2000, P. Derleth (B0121); 2 nymphs, Seturan (1999-petak 39- 40) - Temalat (Sungai Guang), trib. Seturan, 3°00'10''N, 116°32'24''E, 27.III.2001, P. Derleth (B0213); 3 nymphs, Langap Sud (1995) - Ngayo, trib. Rian, 3°04'41''N, 116°31'11''E, 14.VI.2000, P. Derleth (B0410); 4 nymphs, same locality but 08.VII.2000, P. Derleth (B0411); 1 nymph, Seturan (2001-petak 57) - Tamalang, trib. Seturan, 2°59'22''N, 116°30'29''E, 10.IV.2001, P. Derleth (B0513); 5 nymphs, Seturan (2001-petak 57) - Tamalang, trib. Seturan, 2°59'50''N, 116°30'29''E, 19.VII.2000, P. Derleth & F. Béboux (B0521); 8 nymphs, Seturan (2001-petak 57) - Tamalang, trib. Seturan, 2°59'22''N, 116°30'46''E, 18.VIII.2000, P. Derleth & R. Schlaepfer (B0541); 3 nymphs, Seturan (2000-petak 45) - Wok (Sungai Guang), trib. Seturan, 2°59'11''N, 116°33'30''E, 29.VI.2000, P. Derleth (B0631); 8 nymphs, Seturan (2000-petak 44-45) - Wok (Sungai Guang), trib. Seturan, 2°59'12''N, 116°33'11''E, 05.IV.2001, P. Derleth & B. Feldmeyer (B0713); 8 nymphs, Seturan (2000-petak 43) - Temalat (Sungai Guang), trib. Seturan, 2°59'29''N, 116°33'29''E, 04.IV.2001, P. Derleth (B0823); 1 nymph, same locality but 21.VI.2000, P. Derleth & J.L. Gattolliat (B0821); 1 nymph, Seturan (1998-petak 32-33) – Rian, 3°00'57''N, 116°32'16''E, 30.III.2001, P. Derleth (B1013); 1 nymph, Langap Sud (1999-petak 24) – Rian, 3°01'40''N, 116°31'05''E, 11.VII.2000, P. Derleth (B1211); 1 nymph, Seturan (unlogged forest) – Seturan, 2°59'49''N, 116°31'22''E, 27.IV.2001, P. Derleth & M. Sartori (B1513)[all MZL]. 1 female imago, Indonesia, East Kalimantan, Kelian River, tributary of Mahakan River, 250 km West of Samarinda, 13.IX.1992, C. Yule; 12 nymphs; same locality but 7.IX.1990; 1 nymph, Malaysia, Sabah, Liwagu river , north of Kundassan , 915 m., 16–17.VIII.1972, W.L. & J.G. Peters; 1 nymph ibid, but W.M. Beck; 2 nymphs, Malaysia, Sabah, Silau stream, north of Kinabalu National Park headquarters, 1585 m., 11– 16.VIII.1972, W.M. Beck; 1 nymph Malaysia, Sabah, Mantukungam River , Poring Hot Springs , 365 m, 12.VIII.72, W.L. & J.G. Peters [all FAMU] .

Description. Nymph

Body length up to 3.5–4.0 mm and 4.5–5.0 mm in male and female respectively, cerci slightly longer than body length.

General colouration greyish black dorsally; scape and flagellum of the antennae whitish, pedicel blackish; legs yellowish, femora darker, with 4 dark brown maculae on dorsal face, maculae sometimes merging; apex of tibiae brownish ( Fig. 147 ).

Outer margin of head fringed with a row of setae from behind eyes to labrum insertion. Antennae 0.9–1.0 times head width, flagellum with 15–16 articles. Dorsal part of male eyes blackish ( Fig. 147 ). Labrum ( Fig. 24 ) with a wide anteromedian emargination; anterior margin covered by thin setae; dorsal face with a row of long and simple setae ( Fig. 25 ). Mandibles slender with one thin seta in middle of outer margin; right mandible ( Fig. 32 ) with outer incisor composed of one tooth, slightly indented medially; inner incisor with 2 teeth; prostheca reduced, constituted by a group of thin setae; a row of 3–4 long, thin setae below mola and some short setae above mola; outer incisor of left mandible ( Fig. 39 ) composed of one tooth indented basally, inner incisor with 2 teeth inserted transversally, one small and pointed, the other large and rounded, prostheca reduced with one well developed seta; no setae below mola. Maxillae moderately slender, with a well developed canine, 2 dentisetae and 3 long setae on inner apical part and a bunch of long, simple setae at crown; inner margin at base of lacinia with one feathered and long seta dorsally and 2 short feathered setae ventrally ( Fig. 46 ); maxillary palp reduced to a simple seta. Hypopharynx with lingua broad, superlinguae quadrangular, outer margin almost straight, a row of simple and long setae at apex. Labial palp three-segmented, articulation between segments 1 and 2 not visible; segment 3 ca. 2.0 times as long as wide at base ( Fig. 58 ).

Prothorax and mesothorax without tubercles on dorsal face. Forefemur (Fig. 75) dilated, ca. 1.5–1.6 times longer than wide; outer margin covered by stout and long setae, and dorsal face with a transverse row of stout and blunt setae (Fig. 76) almost reaching inner margin; inner margin with a row of long and thin setae almost reaching apex of femur. Foretibia with one visible row of long and thin setae on inner margin, and another on outer margin. Middle femur more slender, ca. 1.9–2.0 times longer than wide; dorsal and inner margins with a row of long and stout setae. Tibia with a row of long and stout setae on inner margin, and a row of long, thin setae on outer margin. Hind leg similar, except femur even more slender, ca. 2.5 longer than wide, outer margin very characteristic and concave. Tarsal claw hooked, with medial 3–4 pointed teeth, and 2 pointed teeth subapically, the inner tooth reduced; apex of claw with two rows of 3–4 thin setae laterally ( Fig. 81 ).

Abdominal terga without median tubercle on segments I–IV, poorly developed on segments V–IX, and none on segment X ( Fig. 149 ). No posterolateral projections on segments II–IV, well developed on segments V–IX ( Fig. 148 ). Gills (Figs. 95–97) on abdominal segments II–IV, gills II with dorsal lamella operculate, oval and with entire margin; gills III with dorsal lamella incised medially; gills IV with dorsal lamella little reduced and entire; ventral lobe flabellate, well developed and purple on gills II–III.

Cerci with stout setae longer than length of corresponding segment.

Female imago. Body length (without cerci): 3.5 mm; Forewing length: 4.0 mm; hindwing length: 0.27 mm

General colouration as in the nymph, especially pedicel blackish, and with the same patterns on femur and tibia. Cerci yellowish, without banding.

Outer margin of hind femora concave. Wings completely hyaline; forewing ( Fig. 14 ) with Sc and R 1 veins dark brown, other longitudinal veins light brown. In addition to character states given in the generic diagnosis, crossveins hardly visible, CuP vein with a short stem. Hindwing almost invisible (less than 0.3 mm length), with a very characteristic shape ( Fig. 15 ).

Egg. Rounded ( Fig. 115 ), ca. 125 µm by 105 µm; chorion without attachment structures and finely pitted which grades to a smooth surface near the polar cap ( Fig. 119 ). Micropyle close to polar cap, and directed transversely to egg axis ( Figs. 118–119 ). Polar cap constituted by two kinds of epithema: a cluster of coiled threads, and small coiled threads arranged in circle around polar cap ( Figs. 116–117 ).

Etymology. This species is dedicated to the youngest daughter of the first author, Miss Eloise Sartori.

Figures

FIGURES 14–15. Derlethina eloisae. Fig. 14: Forewing; Fig. 15: Hindwing.

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 26–32. Right mandible of Oriental Teloganodidae. Fig. 26: Teloganodes tuberculatus; Fig. 27: T. jacobusi; Fig. 28: Dudgeodes hutanis; Fig. 29: D. pescadori (shape of the new mandible in dotted line); Fig. 30: D. celebensis; Fig. 31: D. ulmeri; Fig. 32: Derlethina eloisae. All same scale.

FIGURES 33–39. Left mandible of Oriental Teloganodidae. Fig. 33: Teloganodes tuberculatus; Fig. 34: T. jacobusi; Fig. 35: Dudgeodes hutanis; Fig. 36: D. pescadori (shape of the new mandible in dotted line); Fig. 37: D. celebensis; Fig. 38: D. ulmeri; Fig. 39: Derlethina eloisae. All same scale.

FIGURES 47–58. Hypopharynx (47–49), labium (50) and labial palp (51–58) of Oriental Teloganodidae. Fig. 47: Teloganodes jacobusi (setae on the left superlingua not drawn); Fig. 48: T. hubbardi (half right); Fig. 49: Dudgeodes hutanis (half left); Fig. 50: T. jacobusi; Fig. 51: T. tuberculatus; Fig. 52: T. hubbardi; Fig. 53: D. hutanis; Fig. 54: D. stephani; Fig. 55: D. celebensis; Fig. 56: D. ulmeri; Fig. 57: D. pescadori; Fig. 58; Derlethina eloisae. Hypopharynx at same scale; labium and labial palps at same scale.

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 40–46. Maxillae (40, 41) and detail of the setae on the apico-ventral part (42–46) of Oriental Teloganodidae. Fig. 40: Teloganodes tuberculatus; Fig. 41: Dudgeodes hutanis; Fig. 42: T. jacobusi; Fig. 43: T. kodai; Fig. 44: D. pescadori; Fig. 45: D. ulmeri; Fig. 46: Derlethina eloisae.

FIGURES 77–81. Tarsal claw of Oriental Teloganodidae. Fig. 77: Teloganodes hubbardi; Fig. 78: Dudgeodes hutanis; Fig. 79: D. stephani; Fig. 80: D. celebensis; Fig. 81: Derlethina eloisae. All claws same scale.

FIGURES 115–119. Egg structure of Derlethina eloisae (SEM pictures). Fig. 115: Shape of the egg; Fig. 116: Detail of the polar cap; Fig. 117: Detail of the coiled threads of the epithema; Fig. 118: Detail of the different chorionic structures; Fig. 119: Micropyle area.