Melolontha daliensis Wang & Qiu, 2025

Wang, Fa-Lei, Wang, Zhen, Xiong, Zi-Chun & Qiu, Jian-Yue, 2025, Two new species and one new record of the genus Melolontha Fabricius, 1775 from China (Coleoptera: Scarabaeidae: Melolonthinae), Zootaxa 5618 (2), pp. 206-220 : 207-211

Melolontha daliensis Wang & Qiu , sp. nov.

( Figs 1–12 , 44 )

Type material. HOLOTYPE, male ( MYNU): CHINA: Yunnan, Dali / Yunlong County, Caojian town / alt. 2500m, 13–22. V. 2021 / Zhi-Wu Zuo leg. // HOLOTYPE / Melolontha daliensis / Wang & Qiu det. 2024 ; PARATYPES, 24 males ( MYNU): CHINA: Yunnan, Dali / Yunlong County, Caojian town / alt. 2500m, VI. 2023 / Zhi-Wu Zuo leg. // PARATYPE / Melolontha daliensis / Wang & Qiu det. 2024 ; 1 male ( MYNU): CHINA: Yunnan, Puer / Jingding County, Ailao Mount / Ailaoshan Subtropical Forest / Ecosystem Research Station / alt. 2400m, VI-VII. 2023 / Zi-Chun Xiong leg. // PARATYPE / Melolontha daliensis / Wang & Qiu det. 2024 .

Description of holotype, male. Habitus ( Figs 1–3 ). Length: 32.1 mm, width: 15.2 mm. Body elongate ovoid, distinctly convex in profile

Color. Head, antenna, pronotum, scutellum, ventral surface, and legs dark yellowish-brown; surface of pronotum with weak copper metallic lustre. Entire body with grayish-yellow to yellowish-brown setae, sides of abdominal sternites and propygidium with white patches, densely covered with white setae.

Head. Clypeus rectangular, lateral margin nearly parallel, anterior margin strongly reflexed and straight, apical angles broadly rounded; disc depressed; surface densely, finely punctate, covered with yellowish-brown setae. Frons densely, largely punctate, covered with long grayish-yellow setae, setae arranged concentrically around the middle; setae denser and longer posteriorly and laterally. The maximum transverse head width 1.86 times the interocular distance, ocular canthus setaceous, similar to those on frons.Antenna with 10 antennomeres, antennal club composed of 7 antennomeres, strongly curved in anterior 2/5, 3.1 times longer than antennomeres 1–3 combined ( Fig. 4 ).

Pronotum transverse, disc moderately depressed anteriorly, surface with dense punctures, covered with long grayish-yellow setae, lateral area with moderately short yellowish-brown setae; anterior margin with long hair-like setae, both sides of posterior margin with a triangular area bearing dense, long, grayish-yellow setae. Lateral margin with serration, convergent after middle, posterior 1/2 slightly flat. Anterior angles obtuse, posterior angles sub-right-angle, weakly extended.

Scutellum densely punctate, surface with similar setae to those on disc of pronotum.

Elytra with four costae (costa I as sutural costa), costa I gradually narrowed to the hind angles, costae II and III melted before basal area, fused together at apical protrusion; costa IV feebly developed, start from the inner side of humeral umbone. Elytra with four intervals (interval 4 as area between costa IV and epipleura), interval sparsely, largely punctate, densely with short grayish-yellow setae, outer half of interval IV, interval V, area around apical angles, and area around apical protrusion with denser, shorter, darker setae. Basal area of elytra (between humeral umbone and costa II) with two large semicircles depressed area which covered with dense setae. Basal margin raised.

Pygidium ( Fig. 8 ) triangular, apex rounded and not extended; surface covered with dense, even yellowish-brown setae, lateral margins with long setae.

Ventral surface. Hypomeron, metasternum, and metepistenum overall covered with long, yellowish-brown, hair-like setae, Mesometasternal process short, apex rounded and produced, not beyond mesocoxae ( Fig. 6 ). Surface of sternites densely punctate, covered with rather dense, short setae, also promiscuously with long hair-like setae ( Fig. 7 ); sides with large, triangular patches densely covered with white setae. Disc of propygidium with sparser setae than on sternites, each side with a distinct white band, densely covered with white setae, posterior margin with long yellowish-brown setae.

Legs. Protibia strongly bidentate, terminal tooth prolonged, proximal tooth acute, outer margin of protibia bordered. Mesotibia and metatibia cylindrical, apex widened, both with two unequal length spurs, outer side with a carina pubescent at apical 2/5; surface of mesotibia and metatibia with moderately dense short setae, apex glabrous; inner surface with a row of long setae.

Genitalia (see Figs 9–12 ).

Female unknown.

Variation. Male: body length 27.4–32.1 mm, width 13.6–15.2 mm. Whole body surface with yellowish brown setae, setae on elytra concolorous.

Diagnosis. Based on the long antennal club, elytra densely and evenly covered with setae, bidentate protibia, apical portion of pygidium not narrowed but more or less rounded, short mesometasternal process, plump lateral maculation of dense white setae on abdominal segments 1–5, and symmetrical parameres, this new species is similar to the three species in phupanensis species group from China, Indochina, and India ( Gupta et al. 2023; Li et al. 2010): M. phupanensis Keith, 2008 ( China: Yunnan; Laos, Vietnam); M. arunachalensis Gupta, Keith, Bhunia, Das, Ghosh & Chandra, 2023 ( India), and M. lachungensis Gupta, Keith, Bhunia, Das, Ghosh & Chandra, 2023 ( India). We can distinguish this new species from M. phupanensis by the shorter antennal club ( Fig. 4 ) (antennal club rather long in M. phupanensis , Fig. 25 ), posterior angles of pronotum sub-right-angle, less extended (posterior angles of pronotum acute, rather prolonged in M. phupanensis , Fig. 25 ), and parameres with narrower apical process (with rounded apical process in M. phupanensis , from fig. 16 in Keith 2008), from M. lachungensis by the protibia strongly bidentate (proximal tooth protibia rather weak in M. lachungensis , from fig. 39 in Gupta et al. 2023), scutellum densely and finely punctate (scutellum sparely punctate in M. lachungensis , from fig. 36 in Gupta et al. 2023), lateral patches of abdominal segments ( Fig. 7 ) white, propygidium with elongated white band laterally (lateral patches of abdominal segments yellow, propygidium without white band laterally in M. lachungensis , from fig. 40 in Gupta et al. 2023), and apical process ( Fig. 9 ) of right parameres larger (apical process same sized in M. lachungensis , from fig. 44 in Gupta et al. 2023). Melolontha daliensis new species is rather similar to M. arunachalensis in external characteristics, but the elytra 1.47–1.50 times as long as wide in dorsal view and sides more parallel (1.28 times as long as wide in M. arunachalensis , from fig. 3 in Gupta et al. 2023), proximal tooth ( Fig. 5 ) of protibia acute and slightly prolonged (proximal tooth of protibia sub-right-angle, not prolonged in M. arunachalensis , from fig. 29 in Gupta et al. 2023), lateral patches of abdominal segment 4 larger and more plump (lateral patches of abdominal segment 4 weak in M. arunachalensis , from fig. 32 in Gupta et al. 2023), and dorsal process of parameres different in size, outer side of each parameres strongly ridged (parameres symmetric, outer side of each paramere weakly and rounded bulged in M. arunachalensis , from figs 43, 55 in Gupta et al. 2023).

Chinese name. 大AEDẆDZaek

Etymology. The specific epithet refers to its type locality Dali, Yunnan.

Distribution. Known so far only from the type locality Yunlong county and Jingdong county, Yunnan, China ( Fig. 44 ).

Figures

FIGURE 44. Distribution map of four Melolontha species in this study.

FIGURES 1–3. Habitus of Melolontha daliensis Wang & Qiu sp. nov., holotype. 1, dorsal view; 2, ventral view; 3, lateral view from left. Scale bar: 10.0 mm.

FIGURES 4–12. Diagnostic characters of Melolontha daliensis Wang & Qiu sp. nov.. 4, antenna; 5, protibia; 6, mesometasternal process; 7, lateral view of elytra; 8, pygidium; 9, dorsal view of male genitalia; 10, ventral view of male genitalia; 11, lateral view of male genitalia from left; 12, caudal view of male genitalia. Scale bars: 5.0 mm in A: fig. 4; 5.0 mm in B: fig. 5; 3.0 mm in C: fig. 6; 5.0 mm in D: fig. 7; 5.0 mm in E: fig. 8; 3.0 mm in F: figs 9–12.

FIGURES 25–30. Habitus of Melolontha species. 25, 26, Melolontha phupanensis Keith, 2008, male; 27, 28, Melolontha phupanensis Keith, 2008, female; 29, 30, Melolontha reichenbachi Keith, 2008, male. 25, 27, 29, dorsal view; 26, 28, 30, ventral view. Scale bars: 10.0 mm in A: figs 25–28; 10.0 mm in B: figs 29, 30.