Salcedia Fairmaire, 1899

Balkenohl, Michael, 2020, A genus in disguise. Revision of the genus Salcedia Fairmaire, 1899 with descriptions of nine new species (Coleoptera, Carabidae, Scaritinae, Salcediini), ZooKeys 901, pp. 1-81 : 1

Genus Salcedia Fairmaire, 1899

Salcedia Fairmaire, 1899: 512.

= Zelma Andrewes, 1920: 451.

Type species.

Salcedia perrieri Fairmaire, 1899, by original designation.

Recognition.

Small sized (2.4-4 mm); griseous to piceous species with long oval or elongated shape of the habitus; head semi-circular or campanulate; labrum short, seven-setose; clypeus fused with clypeal wings; frons of head posteriorly with four longitudinal carinae, the median ones more or less joining anteriorly into a keel or tubercle; without clypeal and supraorbital setae; eyes either not at all or to a small extent visible in dorsal view. Head and pronotum ventrally with channel for the reception of the antennae. Pronotum with two conspicuously raised longitudinal carinae at middle, laterally with one to four additional smaller carinae, laterally broadly bent upwards, wing-like, with five or six transverse lateral pits, lateral margin crenulate to varying degrees, without marginal setae. Elytron with carinate suture, with interneurs two, four, and six sharp; lateral interneur (sixth) more or less crenulated, forming outline of elytron, interneurs two and four conspicuously raised, interneur two with distinct tubercle at base, interneur five without carina, one and three in some species with slight to indistinct carina of different lengths. Intervals with one or two longitudinal series of pits. Lateral margin and channel not visible in dorsal view, channel with a series of umbilical setigerous punctures, accompanied by interneurs seven and eight. Elytron without discal setigerous punctures. Metepisternum with longitudinal groove medially for the reception of intermediate tarsomeres and the apical part of the intermediate tibia. At the margin of the last visible abdominal sternum with one setigerous puncture at each side. All tibiae carinate, front and intermediate tarsomeres broadened.

Different from the other genera of the tribe Salcediini , mainly by the antennal channel on the ventral surface of the pronotum, by the metepisternum with longitudinal groove for the reception of the apical part of the intermediate leg, the distinctly carinate tibiae, the less visible eyes in dorsal view, and by the antennomeres two and three which are of the same length.

Redescription.

Measurements: Body length 2.4-4 mm, width 0.9-1.5 mm.

Colour and surface: Anthracite grey to fuscous or piceous, more or less shiny; top of carinae, margins of pronotum and elytra and surface of supra-antennal and supraorbital plates usually opaque, griseous, covered with pale grey pili; mandibles, legs, antennae and palpi paler.

Head: Narrower than pronotum. Outline semi-circular, campanulate or reniform. Surface very sculptured, camouflaged by mud if not cleaned (Fig. 5 ). Clypeus wide, fused with clypeal wings, separated from supra-antennal plates by notches, frons with four carinae, the two median ones often joining anteriorly into a central tubercle or a longitudinal keel, with two small glossy teeth bilaterally below central tubercle, with two shorter carinae paralaterally towards base; frons and clypeus separated from supra-antennal and supraorbital plates by deep broad furrows, each furrow with moderately deep circular pit between supra-antennal plate and clypeus; margins of supraorbital plates distinctly raised. Eyes large, convex, or reduced and concave; convex eyes usually visible to small degree from above, with minute pili between ommatidia. Antenna not flattened, nearly reaching base of pronotum, densely pubescent with shorter and longer fine setae, scapus with short seta at apex, segments two to four scarcely pubescent, segment two and three of same length. Labrum short, covered for the most part by clypeus, seven-setose (example in Fig. 5 ). Mandible short, wide, scrobe asetose. Apical segment of maxillary palpomere securiform, terminal segment of labial palpomere short, bottle like, second segment bisetose. Glossa slender, distinctly arcuate and acute at apex. Paragena with tooth anteriorly. Mentum small, with three pairs of setae, the posterior ones pointing posteriorly, the other ones anteriorly (Fig. 6 ), epilobes wide, projecting and angular anteriorly, more or less margined, surface coriaciate-like, with small grooves or with flat impressions. Ligula broadened and apically truncated, with two setae close together. Head without other setae on dorsal surface.

Pronotum: Outline rectangular, more or less transverse. Anterior margin bilaterally excised, the central projection carinate, fits in and hangs over the posterior excision of the head. Lateral margin straight or convex, crenulated or tuberculated. Anterior and posterior angles distinctly marked. Disc flattened or convex in lateral view, with two distinctly raised paramedian carinae more or less parallel to median line, forming two wide tubercles at base pointing posteriorly, with one to four additional shorter carinae bilaterally of which the three lateral ones are present or not, with narrow median line. Margin laterally bent upwards, wing-like, with five or six large transverse pits. Scutellum small, embedded on peduncle, somewhat hidden. No setae on dorsal surface.

Elytron: Outline convex to parallel. Suture carinate. Interneurs two, four, and six sharp, distinctly to conspicuously raised (Fig. 7 ); lateral interneur (sixth) more or less crenulated, forming outline of elytron, forming pseudohumerus at base, interneur two with distinct tubercle at base, four at base shortened or not, interneurs one and three with or without slight carina, five without carina. If not indicated otherwise the interval on disc between suture and interneur one with two rows of pits towards base and one row of serial pits thereafter, between interneur two and three and three and four with two rows of serial pits, and between interneur four and five and five and six with two rows of serial pits, the latter ones often partly merging transversally. Pits are situated in some species on the declivity of the carinae and are not directly visible in dorsal view. No discal setae. Striole not present.

Hind wings: Fully developed or reduced.

Lower surface: Head with deep channel-like grooves under eyes and at lateral parts of neck for reception of antennae. Pronotum channel-like hollowed out from anterior margin nearly up to base (for reception of antenna, Fig. 6 ). Channel broadened towards base, surface of channel with reticulation. Elytron with lateral margin and channel not visible in dorsal view, channel narrow, accompanied by interneur seven and eight, usually more narrowed at middle, with series of umbilical setigerous punctures situated at small tubercles, interrupted at narrowed part at middle, with upright minute setae. Real humerus indistinct, obtuse-angled, situated latero-ventrally, composed of anterior end of lateral channel and obtuse carina. Pseudoepipleura (lateral interval of elytron, not visible in dorsal view) with one or two rows of pits, densely covered with pili. Lateral margin of elytron smooth or crenulated. Proepisternum carinate anteriorly, at middle and laterally. Metepisternum more or less elongate, with broad longitudinal groove (for reception of terminal part of the intermediate tibia and the intermediate tarsomeres), surface isodiametrically reticulated (Fig. 2 ). Metasternum and last five abdominal sternites with numerous pits, more regularly arranged at carinae and margins. Last four abdominal sternites laterally with traces of reticulation, sternite one and two densely covered with longitudinal reticulation. Sternum four to six sulcate. Last visible sternite bilaterally with one seta of medium size.

Legs: Short, stout. Profemora ventro-basally wing-like dilated, dorsal surface with reticulation. Protibia with three strong short setae on ventral surface, with terminal spine arcuate at apex, laterally dentate to varying degrees, dorsally and ventrally with two carinae. Movable spur small, slightly arcuate, acute, length nearly half as long as first tarsomere; meso- and metafemora slender, slightly dilated basally, mesofemora tooth-like dilated posteriorly at base. Meso- and metatibia nearly square in cross section, with four longitudinal carinae, furnished with robust setae of moderate length. First tarsomere distinctly elongated, not quite as long as tarsomere two to five combined, front legs with tarsomeres two to four distinctly broadened and flattened. Intermediate tarsomeres moderately broadened and flattened. Claws and seta between claws relatively long.

Male genitalia: Median lobe with outline moderately or slightly arcuate, in some species fractuate, apex in some species spatulate. Parameres non-pedunculate, in most of the species asetose, conspicuously asymmetrical with the ventral one very small. The median lobe is similar to the type found in the genus Trilophidius Jeannel, 1957.

Female genitalia: Slender, coxostylus (gonopod IX) one and two fused, distinctly broadened basally, without or with one or two subapical setose organs, usually with one larger often somewhat flattened nematiform seta at beginning of basal third and five to eight slender nematiform setae. Outline similar to that of the clivinine genus Ancus Putzeys, 1866.

Distribution.

Distributed over the whole tropical belt of Africa from the west coast to the east coast, and southward to the north of the Republic of South Africa and of Madagascar. Also known from four localities in the Oriental region (Tharrawaddy, Mandalay, Palon, Calcutta).

Figures

Figure 2. Salcedia baroensis sp. nov., latero-ventral view, basal half of elytron and metepisternum. White arrows: series of umbilical setae arising from tuberculate punctures. Blue arrow: real humerus, yellow arrow: longitudinal groove for the reception of the apical half of the intermediate tibia and the tarsomeres.

Figure 5. Specimen of Salcedia lukulua sp. nov., head, dorsal view a uncleaned b cleaned.

Figure 6. Salcedia species, head and pronotum, ventral view a S. elongata Alluaud b S. baroensis sp. nov.

Figure 7. Salcedia unifoveata sp. nov., habitus, frontal view, cleaned specimen. The space between the suture and interneurs two, four, and six is naturally filled with mud.