Hyphalus shiyuensis, Liu & Xie & Jia, 2020

Liu, Zhen-Hua, Xie, Qiang & Jia, Feng-Long, 2020, Hyphalus shiyuensis sp. nov. from Xisha Islands, China (Coleoptera, Limnichidae, Hyphalinae), ZooKeys 941, pp. 91-99 : 91

Hyphalus shiyuensis sp. nov. Figures 1-9 , 10-13 , 14

Material examined.

Holotype: male, China, Hainan Province, Xisha, Shiyu Reef, in a small salty pool (中国, 海南, 西沙, 石屿), 16°32'42"N, 111°44'53"E, alt. 0 m, 30.viii.2018, Qiang Xie leg. (SYSU). Paratypes: same data as holotype (2 males, SYSU).

Additional material examined.

Hyphalus insularis Britton, 1971. Holotype: Herron I. Gt. Barrier Reef, Q. 24.xi.1968, beneath rocks below high-water mark. E. Britton, S. Misko (ANIC). Paratypes: same data as holotype (75 specimens, ANIC).

Hyphalus wisei Britton, 1973. Paratype: New Zealand Cape Rodney, North I. exposed rock platform opposite Goat I., N. of Leigh 5.xii.68, K.A.J. Wise (dissected for SEM photograph, ANIC). None types: Leigh, NZ G. Kuschel/ Hyphalus wisei Britton ♂ (1 male, ANIC).

Hyphalus kuscheli Britton, 1977. Paratypes: In rock crevice at H. W. M. Napier Bay 6. III. 1945 J. M. GURR/ Bay of Islands Co. North I. ANIC); In rock crevice at H. W. M. below recent spring H. W. M. Napier Bay 6. III. 1948 J. M. GURR/ Bay of Islands Co. North I. (ANIC).

Hyphalus prolixus Britton, 1977. Paratypes: In rock crevice below H. W. M. Otupoho Bay, Moturua, I. 26. III. 1945 J. M. GURR/ Bay of Islands Co. North I. (4 specimens, ANIC).

Diagnosis.

The new species can be separated from the New Zealand species by the broadly ovate body shape. Additionally, the median lobe of aedeagus of H. shiyuensis sp. nov. is the same length as the parameres (Fig. 9 ), thus differing from Seychellois H. crowsoni and H. madli . It can also be distinguished from the Australian H. insularis and Japanese H. taekoae by the curved basal projection of the phallobase, which is similar to H. madli ( Hernando and Ribera 2004: fig. 1).

Description.

Length 1.10-1.22 mm, width 0.62-0.69 mm. Body compact and nearly ovate (Fig. 1 ), dorsum black, venter brown to brownish red, slightly convex both dorsally and ventrally. Vestiture of short and dense silver setae (Fig. 2 ).

Head sub-rectangular, partly retracted in prothorax, not constricted behind eyes; lateral margins slightly curved, posterior margin slightly emarginated; vertex line and occipital incisions absent. Eyes small and very slightly protruding laterally, finely facetted. Antennae closely inserted in front of eyes; insertions concealed by small frontal expansions laterally. Antennae (Fig. 4 ) 11-segmented with a 3-segmented antennal club, scape elongate and slightly enlarged apically, pedicel smaller and cylindrical, basal two antennomeres of antennal club with small angulate projection at outer apical corner, terminal segment dilated and fusiform; antennomeres with sparse alveolate sensorium on the surfaces (Fig. 11 ). Frontoclypeal suture present and straight; clypeus rectangular with apical margin very slightly emarginate; labrum (Fig. 8 ) large and sub-trapezoid, exposed from dorsal side and freely articulated with clypeus. Mandibles (Fig. 5 ) sub-triangular with broad base and narrow apex, lateral margins curved with three apical teeth, dorsal surface with a lateral tubercle at base; prostheca sclerotized and elongated with several apical setae; mola present. Maxillae (Figs 7 , 13 ) with 4-segmented palps, first palpomere shortest, second palpomere elongate and slightly enlarged apically, third palpomere transverse and short, terminal palpomere enlarged and ovate with pointed apex; galea not narrower than lacinia, apex acute; lacinia with dense long setae along the inner edge. Labium (Fig. 6 ) small, labial palps 3-segmented, ligula present and broad. Ventral side of head without sub-antennal suture; gular suture widely separated and diverging posteriorly, gula area short. Cervical sclerites present and large.

Pronotum transverse, ca 0.6 times as long as wide, widest just before posterior angles, lateral margins slightly curved, posterior margin bisinuate, anterior angles acute and extending forwardly, posterior angles acute and extending posteriorly; disc convex, with dense and fine punctations; lateral carinae complete, pronotal epipleuron wide. Prosternum with area before procoxae longer than prosternal process, anterior margin broadly curved; prosternal process broad and parallel sided, apex narrowed with truncate apical margin, extending into the cavities on mesoventrite (Fig. 10 ). Notosternal suture complete. Procoxae slightly transverse with exposed trochantins (Fig. 10 ), widely separated; procoxal cavities sub-rectangular, externally and internally open.

Scutellum small and triangular. Elytra relatively broad, ca 1.1 times as long as wide, widest at about anterior third, lateral margins crenulate, apex with quadrangular projection that fits into incision of last ventrite. Dorsal surface weakly convex with fine punctations; epipleuron broad at base, extending to the apical projection. Hind wings absent. Mesoventrite short with pair of lateral depressions anteriorly and a large central concavity to receive the prosternal process, mesoventral process broad with posterior margin truncate; metaventrite short and nearly flattened, metanepisternum broad, meso-metaventral junction simple, of straight line; metendosternite with short and very broad strut, lateral arms slender, laminae and anterior tendons absent. Mesocoxae ovate and widely separated, trochantins exposed; mesocoxal cavities laterally open to mesepimeron, distance between cavities larger than width of cavities. Metacoxae ovate and widely separated, only a little wider than length. Legs all with brown enlarged femora, trochanters triangular and yellowish; tibiae flattened and expanded; tarsal formula 4-4-4, first three tarsomeres short and yellowish, last tarsomere elongate and enlarged apically with a pair of falciform claws, all with sparse long hairs underneath.

Abdomen (Figs 3 , 12 ) with five ventrites, gradually narrowed posteriorly, covered with dense short depressed setae which are longer on apex; each segment with pair of small posterolateral projections protruding posteriorly, first three ventrites fused and almost equal in length; intercoxal process of first ventrite broad with anterior margin truncate, fourth ventrite shortest, last ventrite sub-trapezoid with pair of small incisions besides posterolateral projections.

Male genitalia with aedeagus trilobate (Fig. 9 ), phallobase long and sub-cylindrical with a small basal projection, parameres slender with rounded apex, median lobe bowling-shaped with apex slight enlarged, nearly the same length as parameres.

Female unknown.

Habitat.

Living in a small pool filled with sea water on a reef.

Etymology.

The new species is named after Shiyu Reef, the type locality. The species name is an adjective.

Distribution.

Only known from the type locality (Fig. 14 ).

Figures

Figure 14. Distribution of Hyphalus shiyuensis sp. nov.

Figures 1 - 9. Hyphalus shiyuensis sp. nov. 1 habitus, dorsum 2 habitus, venter 3 abdomen, venter 4 antenna 5 Mandibles 6 labium 7 maxilla 8 labrum 9 aedeagus. Scale bars: 0.5 mm for (1 - 3); 0.1 mm for (4 - 9).

Figures 10 - 13. Hyphalus shiyuensis sp. nov. SEM images 10 head, prothorax and mesothorax, venter 11 terminal antennomeres 12 pterothorax and abdomen, venter 13 mouthparts.