Liotesba wittmeri Coiffait, 1977

Zhou, Yu-Lingzi & Zhou, Hong-Zhang, 2013, Taxonomy and phylogeny of the genus Liotesba Scheerpeltz (Coleoptera: Staphylinidae: Staphylininae: Xantholinini) with descriptions of four new species, Journal of Natural History 47 (45 - 46), pp. 2869-2904 : 2899-2900

Liotesba wittmeri Coiffait, 1977

Coiffait, 1977: 219 (type locality: Bhutan: Phuntsholing-Thimphu, 1680 m); Herman, 2001: 3692 (catalogue); Bordoni, 2002: 321 (characters); Smetana, 2004: 691 (catalogue).

Material examined. male, with labels as follows: “ Holotype ”/“ PhuntsholingThimphu , 87 1680 m ”/“Nat.–Hist. Museum Basel-Bhutan Expedition 1972”/ “ Liotesba wittmeri H.Coiffait Det. 1975 ”. ( NHMB) .

Description

Measurement. BL = 10.38 mm, FL = 5.88 mm, HL = 1.71 mm, HW = 1.47 mm, PL = 1.86 mm, PW = 1.35 mm, EL = 2.10 mm, EW = 1.56 mm.

Body nearly cylindrical, large-sized. Body dark brown, except elytra reddish. Legs and antennae reddish brown, except basal antennomere dark brown. Maxillary and labial palpi brown.

Head. Rectangular (HL to HW ratio 1.2), tempora straight, posterior angles angulate. Dorsal integument shiny, rather smooth, extensively bearing micropunctures, with few sparsely scattered punctures in large size at the lateral one-third and posterior onequarter surface of head, without any punctures on deflexed portion of tempora. Each side of cranium with anterolateral puncture near antennal insertion, midlateral puncture approximately the distance of three punctures’ diameter from dorsal margin of eye, temporal puncture at the posterior one-fifth, and occipital puncture at the lateral third. Frontal furrows relatively short, anteocular furrows absent. Eye small-sized, equal to one-third the length of tempora (eye: tempora = 0.32: 0.98 mm), not protruding laterad; one large and one small punctures next to dorsal margin of eye. Epistoma broad, subrectangular. Distance between antennal insertions 0.45 mm, being subequal to distance from antenna to eye (0.48 mm).

Antennae. Scape stout, thickened apically, slightly longer than three subsequent antennomeres combined, 0.56 mm; antennomere II slightly elongate or subglobular, 0.20 mm; III distinctly elongate, subequal to II, 0.21 mm; IV and V subequal in length, 0.12 mm; last antennomere short, 0.30 mm, distinctly shorter than two preceding antennomeres combined.

Mouthparts. Labrum transverse, with a pair of median teeth, and a lateral tooth at each side, which slightly protrude forwards. Mandibles falciform, right one with a sharp tooth on inner edge. Maxillary palpus elongate, second segment longest, last segment fusiform with subtruncated apex, as long as the penultimate. Labial palpus slender, each segment equal in length, last segment slightly dilated subapically.

Neck. Wide (0.68 mm), slightly narrower than half the width of head.

Pronotum. Subrectangular (PL to PW ratio 1.4), slightly longer than head, but narrower. Widened anteriad, lateral margins slightly sinuate, anterior angles well defined, posterior angles broadly rounded. Dorsal integument extensively covered with micropunctures, with two large punctures on each anterolateral corner, one large puncture on each posterolateral corner, also with additional irregular punctures near anterior and lateral margins of pronotum.

Mesoscutellum. Shiny, with five or six irregularly scattered punctures.

Elytra. Subrectangular, elongate (EL to EW ratio 1.3), distinctly longer, wider than pronotum. Humeri well developed, lateral margins divergent posteriorly, hind margin rounded. Integument shiny, flattened, without microsculpture; each elytron with a row of smaller punctures along median suture, one or two rows of medium-sized punctures along midwidth, also with three or four rows of punctures on deflexed portion.

Legs. First four segments of protarsi heart-shaped, dilated, but those of mesotarsi and metatarsi slender. Last segment of protarsi and mesotarsi shorter than the II–IV, respectively; last segment of metatarsi subequal to the length of II–IV.

Abdomen. Cylindrical, broadest at segment VI. Tergites III–VII shiny, each segment covered with distinct transverse microstriae, with densely distributed punctures in large size, distance between punctures about two to three punctures’ diameter. Each tergite with a basal impression near anterior margin, bearing transverse microstriae and larger punctures. All abdominal sternites shiny, with microstriae and punctures as those on tergites.

Distribution. Bhutan.

Remarks. Although this species is similar in shapes of antennae and pronotum to L. oculifera Bordoni, 2003 , it can be distinguished from it in the combination of rectangular head with angulate posterior angles, smaller eyes and different distributional pattern of punctures on the head.

Phylogeny and labrum and aedeagus morphological patterns

Phylogenetic analysis produced two most parsimonious cladograms with a length = 154 steps, consistency index = 0.47, and retention index = 0.40. One of them was selected as a reference tree and presented in Figure 6 . The phylogenetic analysis included only 10 Liotesba species ; the other six could not be included in this study because of difficulties in borrowing type specimens. The characters of labrum and aedeagus were mapped on the tree for each studied species to get a perspective view of the evolutionary trend.

As shown in Figure 7 , we could obtain a primary impression of labrum evolution, especially on median teeth. Liotesba fengyangshana sp. nov. of Clade A possesses protruding median teeth on anterior margin of labrum; L. subsimilis of Clade B bears distinctly protruding median teeth; L. expansipalpis sp. nov. has the most protruding median teeth; L. enthymema of Clade C with rather protruding median teeth; L. itoi also possesses protruding median teeth. These data help us suppose that the protruding median teeth of the labrum might have evolved more than once.

The morphological changes of parameres, inner sac and other aedeagus characters are illustrated in Figure 8 . Clade A possesses an unspinulate internal sac, without the obvious bottle-neck median lobe that always presented in other clades. Liotesba expansipalpis sp. nov. and Clade C have a wider, spinulate inner sac and more distinctly bottle-neck median lobe. In Clade B, L. subsimilis has spinulate and complex internal sac, and L. malaisei has unspinulate and simple inner sac. Due to lack the information on the aedeagus of the remaining species of Liotesba , our primary hypothesis that the character of unspinulate internal sac appears in advanced species requires more materials and a more thorough study before it can be fully proved.

Figures

Figure 6. A reference tree produced with 58 characters.

Figure 7. The character of labrum mapped to a reference tree.

Figure 8. The character of aedeagus mapped to a reference tree.