26 STUTTGARTER BEITRAGE ZUR NATURKUNDE Ser. A, Nr. 622 
species but externally very similar to not yet described Microtrichalus was collected 
together with D. striatus. Both species are easily distinguishable under microscope 
by the structure of elytral costae and shape of pronotum. 
Description: 6. Body small, slender, parallel-sided, dark brown to black, prono- 
tum brown, space between costae 1 and 4 at humeri and costae 2 and 4 in further two 
thirds of elytral length light brown. Head small, with rather small eyes, interocular 
distance 1.16 times longer than maximum eye diameter, head shining, covered with 
dense pubescence. Maxillary palpi stout, antennae slender, serrate. Pronotum small, 
transverse, 1.34-1.43 times wider than long at midline, disc shining, with dense brown 
pubescence. Elytra very slender, vestiges of secondary costae throughout whole in- 
terspace between suture and primary costa 2 missing in the rest of the elytra. Phallus 
slender, sclerotized part of internal sac very broad (Fig. 28). 2: unknown. 
Measurements: Length of body 6.0-6.2 mm, width at humeri 1.22-1.25 mm, 
length of pronotum 0.67-0.73 mm, width of pronotum 0.96-0.98 mm. ¢: interocu- 
lar distance 0.44 mm, maximum diameter of eyes 0.28 mm. 
Distribution: New Guinea, known from the type locality only. 
3.25. Diatrichalus tenimberensis (Pic, 1930) (Figs 8, 12-13, 16, 44) 
Mimotrichalus tenimberensis Pic, 1930 (Pic, 1930: 92) 
Diatrichalus tenimberensis (Pic, 1930); BocAx (1998: 193) 
Type material: Holotype d, “Tenimber Is, Coll. by W. DoHErty” (MNHP). 
Other material examined: d, New Guinea, SE, Oni Oni, Port Glasgow, 2. II. 1965, 
leg. R. StRAATMAN, Bishop; — 6 dd, New Guinea, NE, Lae, Singuawa R., 10m, 1.-16. IV. 
1966, O. R. WıLkes, light trap; -— 8, NE, Lae, VII. 1944; — 8, Lae, sea level, 26. VII. 1955, J. L. 
GressitT; — 6, Lae Bubia Agr. Stn., 15 m, 6. VII. 1957, D. ELmo Harpy; - 6, Tapini, 1000 m, 
9.-12. VII. 1968, leg. Mena; - d, NE, Bulolo R., 680 m, 23. IV. 1969, J. SEDLACER; — d, NE, 
Ambunti, Sepik R., 150 m, 4. V. 1963; - 4 & d, Wau, Morobe Distr., 1200 m, different data, J. 
SEDLACEK;— 3 6 6, NW, Nabire, Gelwink Bay, 0-50 m, 2. VII.-4. IX. 1962, J. SEDLACER; - 6, 
Neth. New Guinea, Hollandia area, W. Sentani, Cyclops Mts., 150-250 mm, 19. VI. 1959, T. 
C. Maa; - 2 SG, Biak I, 1. VII. 1962, J. L. Gresstrr; - ¢, New Britain, Linga P, W of 
Willaumez Pen., 11. IV. 1956, J. L. Gressrrr; - d 2 New Guinea, Papua, Normanby I., 
Wakaiuna, Sewa Bay, 1.-10. XII. 1956, W. W. Branpt (BPBM, LMBC); -3 8 4, Papua New 
Guinea Madang env., VI. 1979, W. G. ULLrıicH (MHNG). 
Differential diagnosis: D. tenimberensis differs from other known dark 
coloured Diatrichalus species known from New Guinea in relatively large eyes and 
the shape of male genitalia (Figs 12, 13, 16). 
Redescription: d. Body small to medium sized, dark brown to black. Head 
small, antennal tubercles prominent, followed by deep, broad despression, surface 
shining, eyes very large, hemispherically prominent, maximum eye diameter 
1.01-1.17 times bigger than their interocular distance, antennae quite broad, serrate, 
maxillary palpı with several papillae at outer margin of apical segment. Pronotum 
broad, nearly parallel-sided in basal half, surface shining, densely pubescent, prono- 
tum widest at base, 1.63 times wider than long at midline. Elytra parallel-sided to 
slightly widened posteriorly, primary costae stout, secondary ones very weak, part- 
ly unclear to missing, transverse costae irregular. Male genitalia relatively slender, 
with apparent ventral process and short tubular basal part of phallus (Figs 12-13). 
Measurements: Length of body 6.7 mm, width at humeri 1.66 mm, length of 
pronotum 0.80 mm, width of pronotum 1.31mm. d. interocular distance 0.45 mm, 
maximum diameter of eyes 0.53 mm. 
