Ligulata, HANLEY & ASHE, 1998

Hanley, Rodney S., 2003, Generic revision of the staphylinid beetle tribe Hoplandriini (Insecta: Coleoptera: Staphylinidae: Aleocharinae), Zoological Journal of the Linnean Society 138 (1), pp. 83-140 : 119-122

GENUS LIGULATA HANLEY & ASHE, 1998 (FIGS 19,20)

Ligulata Hanley & Ashe, 1998:184 . Hanley, 2002a:301. Hanley, in press b.

Type species: Ligulata hansoni Hanley & Ashe (1998) by monotypy.

Diagnosis: This genus is distinguishable from the other genera of Platandriina by the following combination of characters: body average in size, 2.4–3.4 mm; eyes average in size, 0.4–0.6 times length of head; apex of galea densely covered with rows of very long hairs, giving appearance of flowing hairs; labial palps with three distinct articles; mesosternum without a medial carina; mesocoxal cavities widely separated, completely separated by meso- and metasternal processes; empodial bristle of hind legs distinctly longer than tarsal claws; apices of abdominal terga with typical macrosetae, not large, heavy, black setae; abdominal tergum IX with a distinct crescentshaped setal pattern; males without secondary sexual features.

Description: In agreement with Platandria description, except for the following characters. [1] Lengths of adults 2.4–3.4 mm. [2] Body ( Fig. 19A ) robust, elongate in dorsal outline, more or less tapering from broad base of pronotum and elytra towards apex of abdomen, [3] surface more or less glossy, evenly pubescent with [4] faintly reticulate microsculpturing.

Head: ( Fig. 19A ) [10] Distinctly broader than long. [11] Eyes moderate in size, 0.4–0.6 times length of head. [13] Infraorbital carina strongly developed and complete. Antenna with [15] articles 1–3 elongate, 2– 8 times longer than wide; [16] segment 4 slightly elongate, 1.2 times longer than wide; [17] articles 5–10 slightly elongate to quadrate; [18] coeloconical sensilla absent.

Mouthparts: Labrum ( Fig. 19B ) with epipharyngeal area with [21] numerous, moderately large pores present between longitudinal sensory field and lateral sclerotized areas ( Fig. 19C ). Mandible ( Fig. 19D,E ) [22] asymmetrical with right with a distinct median tooth, left without median tooth; [23] apex more or less acute and curved adorally; [24] condylar molar patch moderate in size, width less than 1/5 of basal mandibular width, [25] composed of very small denticles, [26] densely arranged in irregular transverse rows; [27] subcondylar molar patch moderate in size, width about 1/4 of basal mandibular width; dorsobasal ‘velvety patch’ [28] very large, width about 2/3 of width of mandibular base, [29] modified into 4 transverse rows of moderately large teeth. Maxilla ( Fig. 19F ) with [31] lacinia about as long as galea, [32] lacinia acute apically, [33] teeth on adoral margin short to relatively long, about 2–15 times longer than wide, with [36] numerous setae and 2 large spinose setae on dorsal surface; [37] galea broad, width subequal to lacinea at widest area, and obliquely truncate apically, [38] membranous in apical 1/2–1/3, [39] densely covered with rows of very long, fine hairs. Labium ( Fig. 19G ) with ligula [45] elongate, as long or longer than labial palpi 1 + 2, [46] broadened apically with [47] rounded apex, [48] with numerous long hairs irregularly arranged; [49] two long medial setae of prementum present, longer than ligula; [53] median pseudopore field narrow and linear, with numerous pseudopores; [55] hypoglossal lobes ( Fig. 19H ) very long, typically reaching to midpoint of ligula, [56] with long, about 3.0–5.5 times longer than width of lobe, comb-like internally curved setae, [57] along entire length of adoral surface. Labial palpi ( Fig. 19G ) [58] elongate, overall length 5.5–7.0 times longer than greatest width, [60] with distal pore field composed of two small, weakly defined pores; [61] segment 1 about 3.7 times longer than segment 2, [62] segment 3 about 2.9 times longer than segment 2. Mentum with [67] many sensory pores more or less uniformly distributed in middle 2/3, primarily near midline.

Thorax: Pronotum ( Fig. 19A ) [68] transverse, [69] about 1.7 times wider than long, [70] strongly convex, about as wide at base as base of elytra. Setae [72] directed primarily posteriorly. Elytra [74] moderately broad, slightly wider apically than basally; [75] apicolateral angles slightly sinuate; [76] elytra together about 1.9–2.2 times as wide as long; microsetae [78] uniformly distributed. Mesocoxal cavities ( Fig. 20A ) [81] widely separated by meso- and metasternal processes, by about 1/4 length of coxal cavities. Mesosternal process [82] longer than metasternal process, extended to basal 5/6 of coxal cavities; [83] meso- and metasternal processes in contact, isthmus absent; [84] mesosternal process slightly rounded to flattened. Metasternum [85] shorter than width of mesocoxae. Legs with [93] empodial bristle longer than tarsal claws; [94] segment 1 of hind tarsus about 1.3 times length of segment 2.

Abdomen: ( Fig. 19A,B ) [97] Narrowly fusiform, tapering apically to broadly pointed apex.

Secondary sexual characteristics: [102,103,104,105, 106,107,108,109] Absent.

Aedeagus: ( Fig. 20C ) Bulb of median lobe [110] more or less elongate, length slightly shorter to subequal to length of tube, [111] with very small ventral projection; [113] parameres ( Fig. 20D ) with apical lobe of paramerite relatively short and narrow, not extended beyond velum; [115] paramerite anterior margin flattened to slightly concave; condylite [117] generally shorter in length to apex of paramerite.

Spermatheca: ( Fig. 20E ) [118] L-shaped; neck, [120] bent at about 90∞ angle; and tube, [121] membranous, loosely curved.

Habitat: Unknown. All specimens of this genus were collected using Malaise traps at 1600 m elevation near Zurqui de Moravia, Costa Rica.

Comments: As mentioned in Hanley & Ashe (1998), specimens of Ligulata superficially resemble those of Platandria . However they differ from this latter genus in structure of the maxilla, the long setose ligula and the broadly separated mesocoxae (see Génier & Klimaszewski, 1986 for a discussion of characters of Platandria ). Ligulata is composed of one species, L. hansoni Hanley and Ashe.

Ligulata appears to be closely related to the genus Bessoglossa with which it shares the following possible synapomorphies: ligula long with numerous long setae at apex; and hypoglossal lobes long, comb-like with long, internally curved setae. Unfortunately, this hypothesis of relationship remains tenuous because I have not been able to study specimens of Bessoglossa . The genus was originally described by Pace (1986) from one specimen of the type species, Bessoglossa peruviana Pace. The specimen was noted in the original publication to have been deposited in the personal collection of Dr Herbert Franz. Unfortunately, repeated attempts to borrow this specimen ended in failure.

Figures

Figure 19. Ligulata hansoni Hanley & Ashe. (A) Habitus, dorsal view. (B) Labrum. (C) Epipharynx. (D) Mandible, dorsal view. (E) Mandible, ventral view. (F) Maxilla. (G) Labium. (H) Hypopharynx.

Figure 20. Ligulata hansoni Hanley & Ashe. (A) Meso- and metathorax. (B) Abdominal tergum IX. (C) Aedeagus, lateral view. (D) Paramere, lateral view. (E) Spermatheca.