taxonID	type	description	language	source
03828798D377646CFDAFF9CDAE27FC50.taxon	description	Figs 1 A, 3 A	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D377646CFDAFF9CDAE27FC50.taxon	description	Diagnostic characters Head frontally not margined. Slightly posterior to frontal edge with a shallow, transverse depression, which medially is vague but still clearly discernible. Pronotum on disc with fine to very fine and sparse punctures (no clearly impunctate area). Pronotal striae at base strongly impressed; striae sinuate (not angled). Basal elytral striae quite long (length of stria almost half the length of elytra). Sutural lines in part vague; frontally and especially, posteriorly the lines are transformed to rows of punctures. Moreover, posteriorly, sutural row fades away; mixed with ordinary elytra punctures. Punctures on each side of elytral striae unequal; between sutural line and elytral stria punctures quite coarse, dense but somewhat irregularly distributed; outside elytral stria punctures distinctly finer and somewhat sparser. Last ventrite of female with a distinct, medial depression which is delimited by distinct, narrow and longitudinal keels. Female elytra outline posteriorly with a small but distinct, lateral expansion (unique character in Bidessus of Madagascar). Penis in lateral view quite slender, curved but medially slightly straightened. Penis apex not distinctly extended (Fig. 3 A). Length of body 1.7 mm.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D377646CFDAFF9CDAE27FC50.taxon	materials_examined	Material examined Paratype MADAGASCAR • 1 ♀; “ envir. de Moramanga ” [around Moramanga]; “ (Q. 1000 c. a) ” [1000 m a. s. l.]; 21 Jul. 1970; N. Sanfilippo leg.; FMNH.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D377646CFDAFF9CDAE27FC50.taxon	distribution	Distribution Endemic species to Madagascar and only known from around Antsirabe and Moramanga (Fig. 4 D). Collecting circumstances poorly known. Sampled at mid (1000 m a. s. l.) and high (1600 m a. s. l.) elevations. Only two specimens are so far known.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D371646DFDE4FB95ACC5FCD5.taxon	description	Figs 1 B, 3 B	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D371646DFDE4FB95ACC5FCD5.taxon	description	Diagnostic characters Head frontally not margined. Slightly posterior to frontal edge with slight depression and anterior to it with three (sometimes four) transversely located, slight but clearly distinguishable tubercles. Pronotum on disc with a rather broad impunctate area. Pronotal striae distinct but not strongly impressed; striae angled and sinuate. Basal striae of elytra distinct but comparatively short. Sutural lines present but quite weakly developed; anteriorly they end clearly before reaching frontal edge of elytra; posteriorly they are transformed to a row of separate punctures slightly behind middle of elytra. Punctures on each side of elytral striae almost similar; fine, slightly irregularly distributed and somewhat sparse. Ventrite apically with distinct and quite dense punctures. Female with outline of elytra posteriorly smooth (minor process absent). Penis (lateral aspect) comparatively robust, evenly curved; (dorsal aspect), quite broad. Penis apex not distinctly extended (Fig. 3 B). Length of body 1.8 – 2.0 mm.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D371646DFDE4FB95ACC5FCD5.taxon	materials_examined	Material examined MADAGASCAR • 5 specs; “ envir. de Perinet riv. Farimbany ” [around Perinet, Farimbany river]; “ (Q 800) ” [800 m a. s. l.]; 18 Jul. 1970; N. Sanfilippo leg.; FMNH.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D371646DFDE4FB95ACC5FCD5.taxon	distribution	Distribution A species as tentatively defined here distributed in East Africa and Madagascar (see Biström 1985). In Madagascar only known from Moramanga and Analamazaotra NP in east central parts (Fig. 4 D). However, Pederzani & Rocchi (2009) identified seven specimens collected in southern Madagascar by Gerecke & Goldschmidt in 2001 as B. ceratus (specimens housed at BMNH and NMW). The series, which we have not studied, was collected north of Ranopiso (25.05 ° S, 46.67 ° E) near the southern part of Andohahela NP and ca 35 km west of Taolanaro.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D371646DFDE4FB95ACC5FCD5.taxon	description	Collecting circumstances According to label information sampled at 800 – 1000 m a. s. l. Taxonomic observation	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D371646DFDE4FB95ACC5FCD5.taxon	discussion	Bidessus ceratus is described from Uganda in eastern continental Africa. When the B. sharpi species group was revised (Bistr ̂ m 1985), specimens from Madagascar were considered to belong to this species. There are, however, features, which indicate the existence of a separate species in Madagascar. No fresh specimens in ethanol are at present available for DNA analyses and accordingly the earlier interpretation is retained.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D370646FFD94FC16AFC4FE23.taxon	description	Figs 2 C, 3 G	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D370646FFD94FC16AFC4FE23.taxon	description	Diagnostic characters Head frontally not margined but provided with a shallow, transverse depression slightly posterior to anterior edge of head (between eyes). Pronotum on disc with a broad impunctate area or with a few fine punctures, distinctly sparser than punctures at frontal and posterior edge. Pronotal striae at base deeply impressed. Pronotal striae with a distinct angle (not smoothly curved). Basal striae of elytra long. Sutural lines distinct; anteriorly and posteriorly lines fade away; transformed to row of punctures. Punctures on both side of basal striae of unequal size; distinctly coarser on inner side. Apical sternite with fine, slightly irregular punctures. Female with outline of elytra posteriorly smooth (minor extension absent). Penis in lateral view slender, curved but medially somewhat straightened. Penis apex not distinctly extended (Fig. 3 G). Length of body 1.6 – 1.8 mm.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D370646FFD94FC16AFC4FE23.taxon	materials_examined	Material examined 283 specimens (BMNH, NHRS, NMW, PBZT / MBC, DEUA) from provinces Antsiranana, Mahajanga, Toliara, Fianarantsoa and Toamasina (see Supplementary File 1).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D370646FFD94FC16AFC4FE23.taxon	distribution	Distribution Endemic species to Madagascar but widely distributed on the island in lowland areas below 800 m a. s. l. (Fig. 4 A).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D370646FFD94FC16AFC4FE23.taxon	description	Collecting circumstances An apt flier that can be collected at light. At low altitudes on both east and west coast, found in a variety of stagnant waters (rice fields, ponds, pools in riverbeds), and in slow-flowing parts of rivers and canals. Often occurs sympatrically with B. perexiguus.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3726460FDC3FE68AFD3F80A.taxon	description	urn: lsid: zoobank. org: act: C 6 F 11 BD 1 - C 6 DC- 41 B 6 - 8994 - 35 C 58 E 062999 Figs 1 C, 3 C	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3726460FDC3FE68AFD3F80A.taxon	diagnosis	Diagnostic characters Head slightly posterior to frontal edge with a shallow, transverse depression, which medially is vague. Pronotum discally with broad area with fine, sparse and irregular punctures. Pronotal striae at base strongly impressed; angled (not smoothly curved). Basal striae of elytra medium long, straight (close to base, strongly curved outwards); at base quite strongly impressed. Sutural lines close to frontal edge of elytra distinct; posteriorly lines gradually fade away. Female with outline of elytra posteriorly smooth (minor process absent). Penis in lateral view curved, medially slightly straightened. Penis apex with a long and slender extension (Fig. 3 C), a feature which separates B. anjozorobe from all other Bidessus species known from Madagascar. Considering morphology B. anjozorobe most resembles B. perrinae Bistr ̂ m, 1985 thus far known from Angola. The two species are separated as follows: elytra almost unicolored dark, black to dark piceous in B. anjozorobe while distinctly bicolored in B. perrinae, elytra being brownish to dark ferrugineous with distinct testaceous markings. Furthermore, body slightly larger and more robust in B. anjozorobe than in B. perrinae (length of body 1.6 mm). See original description in Bistr ̂ m (1985).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3726460FDC3FE68AFD3F80A.taxon	etymology	Etymology Named after the type locality Anjozorobe forest, part of the Anjozorobe-Angavo protected area. The epithet is a noun in apposition (ICZN 11.9.1.2).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3726460FDC3FE68AFD3F80A.taxon	materials_examined	Type material Holotype MADAGASCAR • 1 ♂; Antananarivo former province, Analamanga region, 10 km E of Anjozorobe, Anjozorobe-Angavo protected area, marsh next to the stream in Saha forest; 18.4128 ° S, 47.9439 ° E; 1320 m a. s. l.; 23 Nov. 2014; J. Bergsten, R. Bukontaite, S. Holmgren, J. H. Randriamihaja and T. Ranarilalatiana leg.; collecting event MAD 14 - 78; forest marsh; NHRS-JLKB 000025033. Paratypes MADAGASCAR • 1 spec.; same collecting data as for holotype; NHRS-JLKB 000025034 • 27 specs (preserved in ethanol); same collecting data as for holotype; NHRS-JLKB 000025027 • 5 specs; same collecting data as for holotype; FMNH • 5 specs; same collecting data as for holotype; BMNH • 5 specs; same collecting data as for holotype; PBZT / MBC • 5 specs; same collecting data as for holotype; DEUA • 1 ♂; Antananarivo former province, Analamanga region, 10 km E of Anjozorobe, Anjozorobe Angavo protected area, Antsahabe, circuit bamboo; 18.41266 ° S, 47.9438 ° E; 1341 m a. s. l.; 5 Apr. 2016; T. Ranarilalatiana leg.; collecting event MAD 16 - 40; marsh and stream pool; NHRS-JLKB 000065489 • 1 ♀; same collecting data as for preceding; NHRS-JLKB 000065490. Type locality Madagascar, Antananarivo, Analamanga, Anjozorobe-Angavo Protected Area, Saha forest (18.4128 ° S, 47.9439 ° E) (Fig. 5).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3726460FDC3FE68AFD3F80A.taxon	description	Description Male BODY. Length 1.7 – 1.8 mm. Dorsal aspect as in Fig. 1 C. Angle between pronotum and elytra indistinct. HEAD. Dark brown to dark piceous. Frontally between eyes not margined. Slightly posterior to frontal edge with a shallow, transverse depression, which medially is vague. Shiny although covered with fine, slightly indistinct reticulation; meshes when distinguished are isodiametric. Posterior to cervical line reticulation indistinct; surface is shagreened. With fine, sparse and somewhat irregular punctures. Posterior to cervical line impunctate. Antenna with basal segments 1 – 4 pale, testaceous; segments 5 – 11 darker; brown to piceous. PRONOTUM. Broadest at posterior corners. Sides posteriorly straight; anteriorly clearly curved inwards. Bright testaceous; anteriorly and between striae with narrow blackish to dark brown, transverse area. At posterior corners with vague, darker spots. Discally with broad area with fine, sparse and irregular punctures. At pronotal edges punctures coarser and denser. Shiny, not reticulated. ELYTRA. Black to dark piceous; apically with a vague, paler area. Basal striae medium long and straight (close to frontal edge strongly curved outwards for a short distance). Sutural lines close to frontal edge of elytra, distinct; posteriorly lines gradually fade away. Punctures fine to rather fine, somewhat sparse and with slightly irregular distribution. On each side of elytral stria, punctures of almost equal size and density. Towards apical region punctures become slightly finer. In frontal half of elytra with a lateral row of slightly irregular punctures. Row of punctures form a shallow but clearly discernible furrow which in posterior half disappears. Narrow area between furrow and epipleuron pale brownish and with finer and sparser punctures. Shiny, not reticulated. Epipleura pale brownish. VENTRAL ASPECT. Pronotum testaceous, with lateral edges narrowly blackish. Metathorax, metacoxal plates and abdomen blackish to dark piceous. Rather shiny, reticulation absent. Punctures distributed as follows: metathorax medially with two rows of fine punctures and at frontal and lateral edge with a single row. Metacoxal plates medially with a few scattered punctures and at inner margin of metacoxal lines with a row of punctures. Abdomen at base with irregular coarse punctures and ventrite in apical half with dense, quite coarse punctures. Otherwise ventral aspect almost impunctate. LEGS. Testaceous to brownish. Protarsi slightly enlarged; mesotarsi slender. MALE GENITALIA. Fig. 3 C. Female Similar to male but protarsi not enlarged, narrower than in male.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3726460FDC3FE68AFD3F80A.taxon	distribution	Distribution Endemic to Madagascar and only known from the type locality in Anjozorobe forest, Central Highlands (Fig. 4 C).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3726460FDC3FE68AFD3F80A.taxon	description	Collecting circumstances The type locality is a vegetation rich marsh in a forest glade at an elevation of 1320 m a. s. l. (Fig. 5). Small water pools were visible at the edges of the marsh during the visit at the end of November 2014 but mostly derived through stamping in the vegetation. Anjozorobe-Angavo forest corridor with its westerly location is a higher elevation forest and represents a transition type between typical eastern humid forest and sub-humid high plateau forest.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37F6464FD98FEB5A856FDBC.taxon	description	Figs 1 D, 3 D	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37F6464FD98FEB5A856FDBC.taxon	description	Diagnostic characters Head frontally not margined; provided with a slight depression slightly posterior to anterior edge of head (between eyes); frontal depression is medially broadly vague and indistinct. Pronotum on disc with a broad impunctate area. Pronotal striae at base not deeply impressed, distinctly angled and not smoothly curved. Basal striae of elytra medium long and distinct. Anteriorly sutural lines of elytra disappear abruptly a short distance before reaching frontal edge; posteriorly lines fade away long before reaching apex. Elytra with punctures on each side of basal striae of equal size and density (rather fine, sparse and slightly irregular). Apical ventrite with rather fine, slightly sparse punctuation. Female with outline of elytra posteriorly smooth (minor process absent). Penis in lateral view quite slender and evenly curved; apex distinct (also slightly curved). Penis apex not distinctly extended (Fig. 3 D). Length of body 1.5 – 1.9 mm.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37F6464FD98FEB5A856FDBC.taxon	materials_examined	Material examined MADAGASCAR • 1 ♂; Fianarantsoa former province, Amoron’i Mania region, 3 km south of Ambalamanakana next to RN 7, Ankazomivady forest; 20.7722 ° S, 47.1809 ° E; 1700 m a. s. l.; 1 Nov. 2014; J. Bergsten, T. Ranarilalatiana and S. Holmgren leg.; collecting event MAD 14 - 02; hygropetric rocks and marsh with vegetation; NHRS-JLKB 000025032 • 5 specs (preserved in ethanol); same collection data as for preceding; NHRS-JLKB 000025024 • 1 spec.; same collection data as for preceding; FMNH • 1 spec.; same collection data as for preceding; PBZT / MBC • 1 spec. (preserved in ethanol); Fianarantsoa former province, Matsiara Ambony region, Ranomafana NP, 500 m from the road at Vohiparara village; 21.2397 ° S, 47.3774 ° E; 1110 m a. s. l.; 3 Nov. 2014; J. Bergsten, T. Ranarilalatiana and S. Holmgren leg.; collecting event MAD 14 - 10; small forest lake with floating margins of vegetation; NHRSJLKB 000025025 • 1 spec.; Toamasina former province, Alaotra Mangoro region, 6 km W of Moramanga, Betsabora river by RN 2 near Antsampanana village; 18.9247 ° S, 48.1828 ° E; 900 m a. s. l.; 24 Nov. 2014; J. Bergsten, J. H. Randriamihaja and T. Ranarilalatiana leg.; collecting event MAD 14 - 81; river with side pools; NHRS-JLKB 000025026 • 2 specs; Fianarantsoa former province, ca 9 km SW Ivato, Bemanta (inselberg); 20 ° 40 ′ 00 ″ S, 47 ° 07 ′ 41.5 ″ E; 1531 m a. s. l.; 18 May 2016; Ramahandrison and Manuel leg.; wide and calm portion of small river; CMM • 16 specs; Fianarantsoa former province, along road N 7 between Ambositra and Fianarantsoa, ca 3.5 km S of Ambalamanakana; 20 ° 46 ′ 33 ″ S, 47 ° 10 ′ 53 ″ E; 1702 m a. s. l.; 19 May 2016; Ramahandrison and Manuel leg.; large pond with Nymphaeaceae and surrounding peat bog with Sphagnum and Drosera; CMM • 13 specs; Fianarantsoa former province, ca 8 km WNW of Ranomafana, ca 1 km SW of Vohiparara; 21 ° 14 ′ 51 ″ S, 47 ° 22 ′ 34.5 ″ E; 1134 m a. s. l.; 29 Dec. 2017; Ramahandrison and Manuel leg.; small marsh, very shallow, with small Poaceae and Cyperaceae, along slowly flowing stream; CMM.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37F6464FD98FEB5A856FDBC.taxon	distribution	Distribution First record from Madagascar and here recorded from Ranomafana NP, near Ambalamanakana and Ivato along RN 7 and near Moramanga (Fig. 4 C). As tentatively defined here, the species is distributed in central and east Africa and Madagascar (see Bistr ̂ m 1985; Nilsson & Hajek 2020).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37F6464FD98FEB5A856FDBC.taxon	description	Collecting circumstances On Madagascar found at elevations between 900 – 1700 m a. s. l. The localities are characterized by being vegetation-rich stagnant waters, a pool next to a river, a pond / marsh and small lake with floating vegetation edges. Semi-open to open landscapes. Taxonomic observation Further study on molecular level may reveal that B. cf. nero in Madagascar is in fact a separate species.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3796465FDE2FDF8A910F86A.taxon	description	Figs 2 A, 3 E	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3796465FDE2FDF8A910F86A.taxon	description	Diagnostic characters Head frontally not margined; somewhat posterior to frontal edge (between eyes) with a transverse depression which becomes indistinct medially. Pronotum on disc with a quite broad, almost impunctate area (fine scattered punctures discernible). Pronotal striae quite deeply impressed, distinctly angled (striae not smoothly curved). Basal striae of elytra moderately long, not deeply impressed. Sutural lines distinct; posteriorly they fade away a short distance before apex; anteriorly, distinguished almost up to posterior edge of pronotum. Size of punctures on each side of basal striae rather fine, almost of equal size. Apical ventrite with fine, quite sparse punctures. Female with posterior outline of elytra smooth (no minor extension). Penis, dorsal aspect comparatively broad and short; in lateral aspect curved. Apex of penis not distinctly extended (Fig. 3 E). Body length 1.6 – 1.7 mm. Shiny, dorsally not microsculptured (frontally on head fragments of reticulation distinguished). General color of body dark piceous to blackish. Pronotum discally on each side with a well-delimited, testaceous spot. Elytra with vague, slightly paler, longitudinal markings. Apex of elytra slightly paler. Base of antenna and legs in part slightly paler.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3796465FDE2FDF8A910F86A.taxon	materials_examined	Material examined Holotype MADAGASCAR • 1 ♂; Ankaratra, Tsiafajavona; 2500 m a. s. l.; Jun. 1947; J. Millot leg.; MNHN. [Note that Bistr ̂ m (1985) during his revision of the group, was unable to locate this holotype that we have since rediscovered.] Additional material MADAGASCAR • 1 spec.; Antananarivo former province, Vakinankaratra region, Manjakatompo Stn Forestière, Anosiarivo; 19.34489 ° S, 047.30414 ° E; 2073 m a. s. l.; 24 Jan. 2012; T. Ranarilalatiana and J. H. Randriamihaja leg.; collecting event MAD-MJK 12 - 13; lake near source; NHRS-JLKB 000025031 • 20 specs (preserved in ethanol); same collection data as for preceding; NHRS-JLKB 000024967 • 5 specs; same collection data as for preceding; FMNH • 5 specs; same collection data as for preceding; PBZT / MBC • 5 specs; same collection data as for preceding; BMNH • 5 specs; same collection data as for preceding; DEUA • 18 specs (preserved in ethanol); Fianarantsoa former province, Haute Matsiatra region, Andringitra NP, lake north east of camp 3; 22.17373 ° S, 46.9016 ° E; 2026 m a. s. l.; 2 Dec. 2013; J. H. Randriamihaja and T. Ranarilalatiana leg.; collecting event MAD 13 - 33; small lake in open area; NHRS-JLKB 000025023 • 5 specs; same collection data as for preceding; PBZT / MBC • 4 specs; Fianarantsoa former province, Ankaratra massif, ca 2.7 km WNW of Manjakatompo; 19 ° 21 ′ 57 ″ S, 47 ° 18 ′ 22.5 ″ E; 1814 m a. s. l.; 19 Dec. 2017; Ramahandrison and Manuel leg.; large grassy temporary pond, beneath slope with pine trees, with Conchostraca crustaceans; CMM.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3796465FDE2FDF8A910F86A.taxon	distribution	Distribution Endemic species to Madagascar and known from the Ankaratra and Andringitra mountain massifs in central Madagascar (Fig. 4 C).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D3796465FDE2FDF8A910F86A.taxon	description	Collecting circumstances This is a high-elevation alpine species on Madagascar, only known from above 1800 m altitude. The type material was collected at 2500 m altitude near the Ankaratra peak Tsiafajavona in 1947. TR and Jacquelin Herisahala Randriamihaja found it in an overflooded glade near a source in 2012 at a slightly lower elevation on Ankaratra (2073 m) (Fig. 6 A). Additionally, they discovered the species for the first time outside Ankaratra in a small lake with vegetation at 2026 m elevation in Andringitra NP further south in 2013 (Fig. 6 B). A few specimens were collected in a clearwater grassy pond as low as 1814 m in the Ankaratra mountain by A. T. Ramahandrison and M. Manuel in 2017.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37B6467FDFCFEB5A953FE2C.taxon	description	Figs 2 B, 3 F	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37B6467FDFCFEB5A953FE2C.taxon	description	Diagnostic characters Head frontally not margined but provided with a shallow, transverse depression which medially is indistinct. Pronotum discally with a broad area with fine and sparse punctures; distinctly sparser than punctures at frontal and posterior edge. Pronotal striae at base deeply impressed. Pronotal striae with a distinct angle (not smoothly curved). Basal striae of elytra rather short. Sutural lines distinct; anteriorly and posteriorly lines fade away; anteriorly lines transformed to a short row of a few punctures. Punctures on both side of basal striae fine, sparse and of equal size. Apical ventrite with a few fine, slightly irregular punctures. Female with outline of elytra posteriorly smooth (minor extension absent). Penis in lateral view slender, almost evenly curved. Penis apex slightly extended (Fig. 3 F). Length of body 1.4 – 1.5 mm.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37B6467FDFCFEB5A953FE2C.taxon	materials_examined	Material examined 478 specimens (NHRS, CAS, NMW, PBZT / MBC, BMNH, DEUA) from provinces Antsiranana, Mahajanga, Toliara and Fianarantsoa (see Supplementary File 1).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37B6467FDFCFEB5A953FE2C.taxon	distribution	Distribution Endemic species to Madagascar but as B. longistriga widely distributed on the island in lowland areas below 800 m a. s. l. (Fig. 4 B).	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
03828798D37B6467FDFCFEB5A953FE2C.taxon	description	Collecting circumstances An apt flier that can be collected at light. At low altitude it can occur in a variety of mainly stagnant habitats such as eutrophied ponds, pools in dried out riverbeds, even water-filled wheel tracks. Often occurs sympatrically with B. longistriga, at least in western parts of Madagascar.	en	Bergsten, Johannes, Ranarilalatiana, Tolotra, Biström, Olof (2020): A new species of Bidessus from Anjozorobe-Angavo and a review of Malagasy Bidessus (Coleoptera, Dytiscidae). European Journal of Taxonomy 720: 1-18, DOI: 10.5852/ejt.2020.720.1109
