Psammoecus spinosus Grouvelle 1882
Creators: name: Karner, Michael
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Silvanidae
Psammoecus
Psammoecus spinosus

description: Psammoecus spinosus Grouvelle, 1882
(Fig. 12)
Material examined
1 spm ‘I.R.S.A.C.-MUS.CONGO | Kivu: Kavimvira (Uvira) | (à la lumière) I-1956 | G. Marlier’ (MRAC). 1 spm ‘I.R.S.A.C.-MUS.CONGO | Kivu: Kavimvira (Uvira) | (à la lumière) II/ III-1956 | G. Marlier’ (MRAC). 1 spm ‘COLL. MUS. CONGO | Tanganika: Moba, 780 m. | (à la lumière) XI-1953 | H. Bomans’ (MRAC). 1 spm ‘ Angola: Cazombo, | Alto Zambeze II-1955 | 4987.1 | E. Luna de Carvalho’ (MRAC). 1♂ ‘ Nigeria VdoFR | m State | IV 1975 | J. T. Nedler Coll.’ (MRAC). 1 spm ‘COLL. MUS. TERVUREN | Côte d’ivoire: Bingerville | II.1962 | J. Decelle’, ‘ Psammoecus sp. | D. G. H. Halstead | det. 1978’ (MKF). 1♂ ‘COLL. MUS. TERVUREN | Côte d’ivoire: Bingerville | I/12. III.1962 | J. Decelle’ (MRAC).
Differential diagnosis
Ps. spinosus differs by the very characteristic shape of the pronotum and the distinctly toothed elytral margins from all other African Psammoecus.
Redescription
BODY. Oval, total length 2.40-3.15 mm (Fig. 12A), reddish-brown, elytra with darkened basis and with dark lateral macula near their middle, connected to the darkened suture in posterior half which is connected to another lateral macula close to the apex; the maculae forming a roughly x-shaped pattern on posterior two thirds of elytra. Antennae reddish-brown, 7 th to 10 th antennomeres darker brown, 11 th antennomere bright yellowish, almost white.
HEAD. Wide, temples strongly narrowed immediately behind eyes; width 0.60-0.75 mm, length 0.38- 0.45 mm, 1.58-1.71 times as wide as long. Eyes very large and protuberant, length 0.18-0.23 mm, distance of inner margins 0.36-0.48 mm. Puncturation on vertex irregular, punctures comparatively small and sparse, pubescence composed of moderately long, semierect setae, microsculpture absent. Longitudinal impressions on vertex very distinct, deep, slightly curved, attaining slightly beyond the middle of eyes. Antennae as in Fig. 12B, long and slender, 1.23-1.30 mm long; antennomere proportions as follows: 2.8: 1.0: 1.3: 1.2: 1.3: 1.4: 1.3: 1.0: 1.0: 1.1: 2.2.
PRONOTUM. Transverse, posterior and lateral margins with distinct impressions, close to the middle of the anterior margin with shallow impression; width 0.65-0.83 mm, length 0.45-0.58 mm, 1.38-1.44 times as wide as long. Anterior angle with very distinct group or large teeth; lateral margin characteristic pattern of four teeth; tooth I large with wide basis, teeth II and III almost fused, forming a large forked tooth, tooth IV as large as tooth I; posterior angle with small group of teeth. Anterior margin with a small short tooth right between anterior group of teeth and middle of anterior margin. Puncturation on disc somewhat coarser as on vertex, pubescence as on vertex, microsculpture absent.
ELYTRA. Oval, length 1.55-2.08 mm, combined width 0.98-1.40 mm, 1.46-1.59 times as long as combined width. Rows of punctures on the disc about as wide as interstices; pubescence composed of long semierect setae, directed posteriorly; interstices of lateral rows of punctures with tubercles that are enlarged to form distinct teeth; towards the elytral disc, these teeth become successively smaller. Microsculpture absent.
PARAMERES. Simple, narrowed towards apex, without well-defined basal part. Inner portion of parameres with numerous small setae; apex with one large seta (Fig. 12C).
Remarks
It has not been possible to locate and study type material of Ps. spinosus. However, Grouvelle (1882) provides an illustration that leaves little doubt regarding the identity of this species, given its peculiar habitus.
description: Published as part of Karner, Michael, 2012, A revision of African Psammoecus (Coleoptera, Silvanidae) and descriptions of two new species from the collection of the Musée royal de l'Afrique centrale, pp. 1-31 in European Journal of Taxonomy 17 (17) on pages 26-28, DOI: 10.5852/ejt.2012.17, http://zenodo.org/record/3857844