Microvelia (Picaultia) gracillima Reuter, 1882

Kment, Petr & Carapezza, Attilio, 2022, Heteroptera (Hemiptera) of the Socotra Archipelago I: Introduction, Nepomorpha, Gerromorpha and Leptopodomorpha, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 62 (2), pp. 475-519 : 493-494

Microvelia (Picaultia) gracillima Reuter, 1882

( Figs 32–35 )

Microvelia gracillima Reuter, 1882: 38–39 (original description). Holotype: sex unknown, Ghana: Addah (MZHF). (See nomenclatorial note below.)

Microvelia (Picaultia) gracillima : ANDERSEN & WEIR (2003): 339 (subgeneric placement).

Microvelia azorica Lindberg, 1941: 18–20 , figs 1a–c (original description). Holotype: ♂, Azores: Flores Is., Mato, Ribeira dos Algares (MZHF). Synonymized by LINDBERG (1954: 3).

Material examined. SOCOTRA: Dixam plateau, Tudhen (12°32′42ʺN 53°59′54ʺE), helocrene with Juncus , suction sampler, 1135 m a.s.l., 1 ♂ 2 ♀♀ (ma), Socotra expedition 2012: J. Bezděk, J. Hájek, V. Hula, P. Kment, I. Malenovský, J. Niedobová & L. Purchart lgt. ( NMPC); Hagher Mts., Scand [= Skand] Mt. env. (12°34′36ʺN 54°01′30ʺE), open helocrene in montane evergreen forest, 1450 m a.s.l., 16.–18.vi.2012, 18 ♂♂ 15 ♀♀ (ap), Socotra expedition 2012: J. Bezděk, J. Hájek, V. Hula, P. Kment, I. Malenovský, J. Niedobová & L. Purchart lgt. ( ACPI, NMPC, MMBC, NHMW).

Identification. POISSON (1941b) (key, redescription, figures), HOBERLANDT (1951a) (redescription, figures); HOBERLANDT (1951b) (key); SCHMITZ (1976) (redescription, figures); LINNAVUORI (1986a): 38 (figures); SALEH AHMED & GADALLA (2005a): 221, 224 (key, diagnosis, figures).

Habitat. In Socotra collected twice at higher altitudes of Hagher Mts. (montane and high-montane zone), in a helocrene overgrown with grass and Juncus socotranus in pastures with sparse shrubs and small trees at Tudhen (1135 m a.s.l., collected by suction sampler; Fig. 52 ), and on miniature pools (10–20 × 10–20 cm) scattered among waterlogged grasses in an open helocrene surrounded by dense montane evergreen forest at Skand Mt. (1450 m a.s.l.; Fig. 51 ). Many copulating couples were observed at Skand locality.

In East Africa, HYNES (1955) collected this small species frequently and on very varied types of habitat. At high altitudes (over 1600 m a.s.l.) in Kenya and Ethiopia, both apterous and macropterous specimens were found on slow streams, ditches and lakes, where they occurred among vegetation. At lower altitudes, down almost to the sea level, only fully macropterous specimens were found. These occurred on both permanent and temporary rivers and pools, and the species appeared on temporary pools very far from permanent water soon after rain. It can travel distances of at least 80 km, even though they may be aided in their flight by turbulence under rain clouds.

According to LINNAVUORI (1971, 1981, 1994b), it lives among dense vegetation in rivers and pools; often collected at light. In Senegal, the species was collected in small pools in the steppe as well as in a garden ( JACZEWSKI 1926). In Zimbabwe, it was collected in small ephemeral pools without emergent vegetation situated in the open grassland ( WEIR 1966). In the Cape Verde Islands, it was collected mainly in running, more rarely in stagnant waters, such as still, vegetated water in meanders of brooks or in pools ( LINDBERG 1959). In the Azores, the type series of M. azorica was collected in a freshwater pool between rocks on the sea coast ( LINDBERG 1941).

Distribution. Afrotropical Region: Angola ( HOBERLANDT 1951a), Benin ( LINNAVUORI 1981), Burkina Faso (LINNAVUORI 1981), Cameroon ( POISSON 1948a, LINNAVUORI 1981), Cape Verde Islands ( LINDBERG 1959), Central African Republic ( LINNAVUORI 1981), Chad ( LINNAVUORI 1981), Comoros ( POISSON 1957d, 1959a), Democratic Republic of the Congo ( KIRKALDY 1900b; BERGROTH & SCHOUTEDEN 1905; POISSON 1942, 1954b, 1968a; LINNAVUORI 1973a), Eritrea ( MANCINI 1961), Ethiopia ( MANCINI 1954, 1961; HYNES 1955), Ghana ( REUTER 1882, LINNAVUORI 1981), Guinea ( POISSON 1960b, BERTRAND 1962), Ivory Coast ( POISSON 1968b; LINNAVUORI 1975, 1981; SCHMITZ 1976), Kenya ( HYNES 1955), Madagascar ( POISSON 1949b, 1951a), Mali ( POISSON 1960b), Namibia ( POISSON 1957a), Niger ( POISSON 1941b, 1950a), Nigeria ( LINNAVUORI 1981), Republic of the Congo ( BERTRAND 1962, POISSON 1967), St. Helena Island ( SCHMITZ 1976), Senegal ( JACZEWSKI 1926, POISSON 1941b), Somalia ( MANCINI 1949, 1954; HYNES 1955; LINNAVUORI 1986b), South Africa ( POISSON 1957a), South Sudan ( LINNAVUORI 1971), Sudan ( LINNAVUORI 1971), Tanzania ( POISSON 1960a), Togo ( LINNAVUORI 1981), Uganda ( POISSON 1941b), Zimbabwe ( WEIR 1966). Palaearctic Region: North Africa: Algeria ( POISSON 1953), Azores ( LINDBERG 1941, as M. azorica ; LINDBERG 1960, as M. gracillima f. azorica ), Canary Islands ( LINDBERG 1953, BAENA & BÁEZ 1990, ROCA- CUSACHS et al. 2020), Egypt (SALEH AHMED & GADALLA 2005b, no exact record; HEISS et al. 2022), Madeira ( LINDBERG 1960, as M. gracillima f. azorica ; LINDBERG 1961, as M. gracillima ; HOBERLANDT 1967, as M. g. azorica ). Near East: Egypt: Sinai ( SALEH AHMED & GADALLA 2005a,b), Iraq ( LINNAVUORI 1994b), Israel ( FURTH 1983), Saudi Arabia ( LINNAVUORI 1986a), Socotra (this paper). New species for the Socotra Archipelago.

Nomenclatorial note. SCHMITZ (1976: 329) failed to locate the type material of M. gracillima in MZHF and NHMW and designated a neotype: ‘ Côte d’Ivoire (J. Decelle, VII-VIII.1962, coll. Mus. Tervuren)’. However, in case of discovery of the original type material such neotype designation would be invalid. The status of the types of M. gracillima requires further investigations.

Figures

Figs 32–39. 32–35 – Microvelia gracillima Reuter, 1882: 32–33 – apterous morph from Skand Mt.: 32 – ♂ (body length 1.76 mm), 33 – ♀ (1.86 mm); 34–35 – macropterous morph from Tudhen: 34 – ♂ (1.76 mm), 35 – ♀ (1.96 mm). 36–37 – M. macani Brown, 1953, apterous morph from Homhil, Ain Tsahrin: 36 – ♂ (1.57 mm), 37 – ♀ (1.76 mm). 38–39 – M. popovi Brown, 1951, apterous morph from Firmihin: 37 – ♂ (1.37 mm), 38 – ♀ (1.96). (Orig. P. Kment).

Figs 49–53.49 –Arher,a spring near the sea coast (5 m a.s.l.), habitat of Ochterus papaceki Kment & Carapezza,2020,Anisops debilis socotrensis Brown, 1956, Mesovelia vittigera Horváth,1895,Hebrus kanyukovae sp.nov.,Microvelia macani Brown,1953,Rhagovelia infernalis socotrensis Brown,1956 and Micracanthia ornatula (Reuter,1881).50– Wadi Madar (1,170 ma.s.l.), habitat of Anisops d.socotrensis, A.varius Fieber,1851,Mesovelia vittigera, Microvelia macani, and Rhagovelia i. socotrensis. 51 –Skand Mt.,helocreneunder the top (1,450 ma.s.l.), habitatof Microvelia gracillima Reuter,1882 andSaldula niveolimbata (Reuter, 1900). 52 – Tudhen, helocrene (1,135 m a.s.l.), habitat of Mesovelia vittigera, Hebrus sp., and Microvelia gracillima Reuter, 1882. 53 –Wadi Zerig with a large pool (655 m a.s.l.), habitat of Micronecta eupompe Hutchinson, 1930, Sigara hoggarica Poisson,1929,Anisops d.socotrensis, A.varius, Hebrus kanyukovae sp.nov.,Limnogonus cereiventris (Signoret,1862), andMicracanthia ornatula. (Orig.P.Kment:Figs 49–52;J.Hájek:Fig.53).