Lasioglossum (Evylaeus) urumaense Murao

Murao, Ryuki, Tadauchi, Osamu, Goubara, Masashi & Maeta, Yasuo, 2010, Taxonomy of the carinaless group of Lasioglossum (Evylaeus) (Hymenoptera, Halictidae) from the Ryukyu Islands, Japan, with description of seven new species, Zootaxa 2669, pp. 1-33 : 19-23

Lasioglossum (Evylaeus) urumaense Murao sp. nov.

( Figs. 11 , 12 )

Description. Female. Body length 5.5–6.2 mm, wing length 4.9–5.7 mm (n= 5).

Color. Tegula brown or blackish brown translucent. Posterior margins of metasomal terga narrowly blackish or reddish brown translucent or entirely black.

Pilosity. T1 ( Fig. 12 C) medially with moderately dense simple and short hairs. Metasomal terga with neither basal hair bands nor apical fimbriae.

Structure. Head wider than long; head length/width ratio 0.89–0.96 (n= 10). Interocellar distance subequal to ocellocular distance. Frons and paraocular area dull, reticulate-punctate. Supraclypeal area ( Fig. 11 B) dull, with dense PP; IS with distinct tessellation. Clypeal length 1.2x distance between ventral rim of antennal socket and dorsal margin of clypeus, with moderately dense PP on upper half, and with larger shallow PP on lower half; IS smooth on the entire surface. Basal area of labrum 2.4x as wide as long; distal process with small lateral projections; keel of distal process moderately broad, apically pointed in frontal view. Scape length 0.7–0.8 mm (n= 5). Mesoscutum ( Fig. 11 C, D) dull, with dense PP and IS with distinct tessellation on the entire surface. Mesoscutellum ( Fig. 11 E) similar to mesoscutum in sculptures. Mesepisternum ( Fig. 11 F) shiny, with dense PP and IS smooth on upper area, and with coarse rugulae on lower area. Propodeal dorsum ( Fig. 11 N) 0.7x mesoscutellum, and 1.3x as long as metanotum, with longitudinal ridges on the entire surface; dorsomedial ridges long, attaining or sometimes not attaining to posterior margin; propodeal side weakly rugulose, with distinct tessellation; lateral slope with weak rugulae; shield with weak tessellation. Inner hind tibial spur ( Fig. 11 O) with 4–6 teeth (n= 30). T1 ( Fig. 12 C) medially with moderately dense obscure PP, and without lineolation on the entire surface. T2 basally and medially without lineolation, and apically with weak lineolation. T3–T4 similar lineolation with T2 on the entire surface.

Male. As in female except as follows. Body length 5.0– 5.4 mm, wing length 4.4–4.7 mm (n= 3).

Color. Mandible medially yellow; labrum yellowish brown; lower half of clypeus slightly dark yellow or entirely black.

Pilosity. S4–S5 posterolaterally with fine branched hairs, moderately dense and long (as in Fig. 6 B).

Structure. Head length/width ratio 0.93–0.97 (n= 3). Clypeal length 1.4x distance between lower rim of antennal socket and upper margin of clypeus. Basal area of labrum 3.3x as wide as long; distal process absent. Scape length 0.4–0.5 mm (n= 3), F2 1.3x F1. Mesoscutum shiny; IS anteriorly and medially with weak tessellation, posteriorly smooth. Mesoscutellal IS smooth. Mesepisternum ( Fig. 11 L) with moderately dense PP on the entire surface. Propodeal dorsum ( Fig. 11 Q) 0.9x mesoscutellum, and 1.3x as long as metanotum; dorsomedial area with ridges on basal half, and nearly smooth on apical half. Basitibial plate of hind legs without carina marginally. S7–S8 ( Fig. 12 H): S7 with moderately long, apically rounded median process; S8 without median process. Genitalia as in Fig. 12 E–G. Gonobasal ventral arm ring-shaped, and not connected to each other at apical ends; bottom nearly flat. Gonocoxite with distinct tessellation on apical inner area in dorsal view. Gonostylus truncate apically in lateral view, with sparse short hairs. Retrorse lobe ( Fig. 12 G) long, apically wider than basally, with moderately dense simple and short hairs.

Remarks. Within the sexstrigatum -group, this new species is closely similar to Lasioglossum (Evylaeus) japonicum (Dalla Torre) from Japan proper and L. (E.) canaliculatum sp. nov. from the central Ryukyus. But it is separated from the former by the following morphological characters: female postgena with distinct lineolation that attains to hypostomal carina apically, male F2 1.3x F1, male clypeus entirely black or slightly dark yellow on the lower half, and dorsal gonocoxite without longitudinal lineolation on lower area. In contrast, in L. (E.) japonicum , female postgena with weak lineolation that does not attain to hypostomal carina apically, male F2 nearly as long as F1, male clypeus with distinct yellow spot on lower half, and dorsal gonocoxite with weak longitudinal lineolation on lower half. For the differences between this species and the latter one see the key. So far as the first author surveyed in Amami-Ôshima, this species was found from lowland to mountain areas.

Etymology. The specific name of this new species, “uruma”, means the coral island.

Distribution. Japan (central Ryukyus: Amami-Ôshima, Okinawa-jima).

Flight records. Female: March to October. Male: July to October.

Flower records. The flowering plants visited by this species were five species in two families listed as follows. Asteraceae : Bidens pilosa var. minor ; Eupatorium variabile ; Vernonia cinerea ; Youngia japonica . Polygonaceae : Persicaria longiseta .

Type material. Holotype (Type No. ELKU 3304): female, Santarou-touge, Sumiyou-son, Amami- Ôshima, Kagoshima Pref., Ryukyus, Japan, 15. x. 2004 (R. Murao leg., RMPC). Paratypes: [Ryukyus: JAPAN] Amami-Ôshima, Kagoshima Pref.: 8 females and 1 male, Mt. Yuwan-dake, 31. vii. 1963 (J. L. Gressitt, ELKU), 26. iii. 2003 (R. Murao, RMPC), 14. x. 2004 (R. Murao, RMPC); 1 female, Santarou-touge, Gusuku-Nishinakama, 15. vii. 1933 (T. Esaki & K. Yasumatsu, ELKU); 4 females and 1 male, same locality as the holotype, 15. x. 2004 (R. Murao, RMPC), 21. ix. 2006 (R. Murao, RMPC); 3 females, Shinmura, 4–5. iv. 1956 (S. Miyamoto, ELKU); 1 female, Shinokawa, 15. v. 1953 (T. Shiraki, ELKU); 8 females and 1 male, Yuwan, 31. vii. 1963 (Y. Hirashima, ELKU); 1 female, Kinsakubaru, 31. v. 2004 (T. Mita, RMPC). Okinawajima, Okinawa Pref.: 1 female, Hedo, 5. iv. 1979 (K. Ohara, ELKU); 1 female, Kunigami-son, 21. v. 2003 (R. Murao, RMPC); 1 female, Mt. Katsuu-dake, 10. viii. 1987 (T. Murota, RMPC); 4 females, Mt. Nago-dake, 20–23. v. 2004 (T. Mita, RMPC), 23. v. 2004 (T. Mita, RMPC); 1 female, Mt. Yonaha-dake, 6. viii. 1987 (T. Murota, RMPC); 1 female, Oku, 13. viii. 1987 (C. Nozaka, RMPC); 119 females, Yona, 26. iv. 1965 (Y. Hirashima, ELKU), 19. iii. 1972 ( ELKU).

Type depository. The type series are deposited in ELKU.

Figures

FIGURE 6. Lasioglossum (Evylaeus) canaliculatum Murao, sp. nov. A, C: holotype, female. B, D, E – H: paratype, male. A: head in frontal view. B: metasomal sterna. C, D: first metasomal tergum (left half, sculpture; right half, hair pattern). E – G: male genitalia (E: left, ventral view; right, dorsal view. F: lateral view. G: retrorse lobe). H: seventh and eighth metasomal sterna. Scale bars: A, B, C, D, 1 mm; E, F, H, 0.2 mm; G, 0.1 mm.

FIGURE 11. Lasioglossum (Evylaeus) urumaense Murao, sp. nov. A – F: holotype, female. M – O: paratype, female. G – L, P, Q: male, paratype. A, G: lateral habitus. B, H: lower face. C, I: mesoscutum. D, J: sculpture on mesoscutum. E, K: mesoscutellum. F, L: mesepisternum. M, P: labrum. N, Q: propodeal dorsum. O: inner hind tibial spur. Scale bars: N, 0.5 mm; M, P, Q, 0.25 mm; O, 0.2 mm.

FIGURE 12. Lasioglossum (Evylaeus) urumaense Murao, sp. nov. A, C: holotype, female. B, D, E – H: paratype, male. A, B: head in frontal view. C, D: first metasomal tergum (left half, sculpture; right half, hair pattern). E – G: male genitalia (E: left, ventral view; right, dorsal view. F: lateral view. G: retrorse lobe). H: seventh and eighth metasomal sterna. Scale bars: A – D, 1 mm; E, F, H, 0.2 mm; G, 0.1 mm.