Tricosa uniseriata, a new species of xyleborine ambrosia beetle from Thailand (Coleoptera, Curculionidae, Scolytinae, Xyleborini) Author Sittichaya, Wisut https://orcid.org/0000-0001-6200-1285 Agricultural Innovation and Management Division, Faculty of Natural Resources, Prince of Songkla University, Had Yai, Songkhla, 90112, Thailand wisut.s@psu.ac.th Author Cognato, Anthony I. Department of Entomology, Michigan State University, 288 Farm Lane, 243 Natural Science Bldg., East Lansing, MI 48824, USA text ZooKeys 2023 2023-03-15 1153 97 103 http://dx.doi.org/10.3897/zookeys.1153.101985 journal article http://dx.doi.org/10.3897/zookeys.1153.101985 1313-2970-1153-97 600808336C7E423D91EEB48F9D96A7CB AEF57F075B5651C68617F6CB6020E022 Tricosa uniseriata Sittichaya & Cognato sp. nov. Fig. 1A-F Type material. Holotype , female, Thailand, Narathiwat Province, Hala-Bala Wildlife Sanctuary, 5°48'02.4"N , 101°49'58.2"E , lowland tropical rainforest, 140 m a.s.l., 12.x.2021, ex. small branch of Artocarpus integer (W. Sittichaya) (NHMW, Naturhistorisches Museum Wien, Wien). Similar species. T. hipparion Smith, Beaver & Cognato, 2022. Diagnosis. This species is distinguished by its stoutness: 2.35 mm long, 2.40 x as long as wide. The combination of the following characters is diagnostic: lateral margin of elytra feebly broadened apically; elytral disc convex; discal striae and interstriae uniseriate punctate; stria weakly impressed and interstriae elevated; anterior margin of pronotum with six moderate serrations. Description (female). 2.35 mm long, 2.40 x as long as wide. Body dark brown, except appendages yellowish brown. Body more robust, less elongate. Head : epistoma entire, transverse, lined with a row of short, hair-like setae. Frons flat from epistoma to middle level of eye, then slightly convex upward to vertex; lower portion of surface at medial line shagreened, subshining; sides of medial line glabrous, strongly shinning; upper portion shagreened, subshining; frons with widely separated, small granules, with each granule decorated with long, fine, hair-like setae. Eyes weakly emarginate above level of antennal insertion; upper portion of eyes slightly smaller than lower part. Submentum slightly impressed below genae, widely triangular at base. Antennal club type 3 ( Hulcr et al. 2007 ; Smith et al. 2020 ); scape regularly thick, as long as club. Antennal funicle four-segmented; first segment longest and other segments approximately equal in length. Pedicel shorter than funicle. Club flattened, approximately circular (type 3) ( Hulcr et al. 2007 ; Smith et al. 2020 ); segment 1 corneous, transverse on anterior face, occupying basal ~1/3; segment 2 slightly concave, corneous and corneous line very narrow; segments 1 and 2 present on posterior face. Figure 1. Tricosa uniseriata sp. nov. holotype female A dorsal view B ventro-lateral view C posterolateral view D front E declivity F antenna. Pronotum : 1.0 x as long as wide; elongate and parallel sided in dorsal view, type 7 ( Hulcr et al. 2007 ; Smith et al. 2020 ); sides parallel in basal 2/3, rounded anteriorly; anterior margin with a row of six serrations. In lateral view, elongate, disc longer than anterior slope, type 7, summit low, on apical 2/5. Surface alutaceous, anterior 1/2 asperate; asperities robust, close together, arranged in concentric arcs from midpoint of pronotum to anterior and anterolateral areas; disc evenly punctate, punctures moderate in size, round and deep, sparse and separated by glabrous, shinning areas 3-5 x the size of puncture, each puncture with short, erect, hair-like seta, some longer hair-like setae at margins. Lateral margins obliquely costate. Base transverse, posterior angles acutely rounded. Scutellum : small, narrow, linguiform, flush with elytra, shiny. Elytra : 1.36 x as long as wide, 1.44 x as long as pronotum. Base transverse, margins oblique; humeral angles rounded. Sides subparallel, slightly broader from base to apical 3/4, then attenuate at apical 1/4, apex attenuate, broadly rounded. Disc convex, surface smooth, shinning, striae and interstriae uniseriate. Striae feebly impressed, punctate, punctures round, broad, and shallow, separated by 1/2 the width of a puncture, each puncture with a short, fine, inconspicuous, hair-like seta. Interstriae feebly elevated, elevation more evident apically; interstriae minutely uniseriate punctate-granulate, widely spaced, near elytral base with fine punctures and small granules on apical 1/2, granules slightly increasing in size apically; each puncture or granule with a very long, hair-like seta. Declivity occupying ~1/3 of elytra, gradual, face feebly convex, subshining; striae feebly impressed, punctate, punctures similar in size with those on the disc, each with short, fine, hair-like seta; interstriae feebly elevated, with small granules, granule apices curved ventrad, each granule with very long hair-like seta; setae on declivity twice as long as those of disc. Posterolateral margins rounded and granulate. Legs : procoxae contiguous, prosternal posterocoxal piece conical, slightly inflated. Protibiae distinctly triangular, broadest at apical 1/3, posterior face flat, unarmed; outer margin armed with five large denticles at apical 1/3. Meso- and metatibiae obliquely triangular, flattened, posterior face unarmed; outer margin armed with 6 and 10 moderately socketed denticles. Male. Unknown. Etymology. L. uniseriata : uni - = one; series = row. Refers to the arrangement of strial and interstrial punctures in one line. A variable adjective. Distribution. Thailand (Narathiwat Province). Host plants. The holotype was collected from a small branch of Artocarpus integer (Thunb.) Merr. ( Moraceae ).