Nebrioporus mascatensis (Régimbart, 1887)

Toledo, Mario, 2009, Revision in part of the genus Nebrioporus Régimbart, 1906, with emphasis on the N. laeviventris-group (Coleoptera: Dytiscidae), Zootaxa 2040, pp. 1-111 : 60-61

Nebrioporus mascatensis (Régimbart, 1887)

Figs 39, 64

Hydroporus mascatensis Régimbart(1887: 206) (orig. descr.); Régimbart (1899: 198).

Deronectes (Potamodytes) mascatensis (Régimbart) ; Zimmermann (1919: 189; 1920: 128).

Deronectes (Potamonectes) mascatensis (Régimbart) ; Zimmermann (1933: 178).

Potamonectes mascatensis (Régimbart) ; Guignot (1960: 320); Wewalka (1974: 109); Brancucci (1984: 235).

Nebrioporus (s.str.) mascatensis (Régimbart) ; Nilsson & Angus (1992: 287); Nilsson (2001: 171; 2003: 67); Hájek & Fery (2004: 38).

Deronectes insignis (Klug, 1833) ; sensu Peschet (1914: 227) (misidentified).

Deronectes (Potamodytes) insignis (Klug) ; Zimmermann (1920: 127 partim; 1921: 17).

Deronectes (Potamonectes) insignis (Klug) ; Zimmermann (1933: 178) (partim).

Potamonectes insignis (Klug) ; Zaitzev (1953: 217) (partim); Vazirani (1970: 120).

Type locality. Oman > Mascat [Muscat] .

Type material. Lectotype ♂ ( MNHN), designated by Wewalka (1974). A further syntype ♂ found in IRSNB with the following data: "Mascate [Régimbart hw. —glued on IRSNB label "Coll.R.I.Sc.N.B. Oman Muscat col. Maindron"] \ Hydroporus mascatensis Rég. Type [Régimbart hw. —glued on additional IRSNB label "det. Régimbart 1897 "] \ Cotype [red rectangular IRSNB label]". This latter must be considered paralectotype, accordingly with Recommendation F of Article 74 of the ICZN (1999).

Additional material examined. Afghanistan: Kouh-Bihkheh [?], 900 m, 19.IV.1958, Coll. R. Mouchamps (1 ex. IRSNB) ; O. Afghanistan, Prov. Nengrahar, D. Povolný et coll., Tor-Khama , 858–900 m, 3.IV.1967 (8 exs. MMBC) .

Iran: Bushehr Prov., 46 km W Kagan , 31.III.90, leg. K. Elmi (1 ex. HF) ; Fars, road Evaz to Lar , 56 km W Lar, pond m 960, 31.III.93 (2 exs. MTP) ; Bushehr, Kangan , 30.III.90 (2 exs. MTP) ; E Iran, Isin [Pa Tall–e Isin? Nr. Bandar –e Abbas], 11–15.V.1973, Loc. n. 143 exp. Nat. Mus. Praha (15 exs. NMPC) ; Kerman, nr. Mechran , 19.III.1901, N. Zarudni (1 ex. MIZIT) ; S. Iran, Jashak , 60 km SE Khormuj [Kerman Prov.], 20–21.IV.1977, Loc. n. 143 exp. Nat. Mus. Praha (1 ex. NMPC) ; SE Iran, 40 km SW Zaboli [Sistan va Baluchestan Prov.], 31.III.1973, Loc. n. 143 exp. Nat. Mus. Praha (1 ex. NMPC) ; In addition I have seen in CBSU specimens from a number of localities of the following provinces: Esfahan (2 exs.); Khuzestan (97exs. from 9 localities) ; Bushehr (36 exs. from 3 localities) ; Hormozgan (3 exs. from 3 localities) ; Kerman (1ex.) ; Sistan va Baluchestan (45 exs. from 6 localities) .

Oman: 50 km W Ar Rustaq , 1000 m, rest-pool of rivulet, 12.II.98, leg. Wewalka (5) (36 exs. GWW) .

Pakistan: Baluchistan, 90 km SSE Quetta, Kundlani , 20–23.II.1995, leg. Hauck et Cizek (31 exs. NMW) ; Baluchistan, Kuzdar Distr., Awaran , 8–19.IV.1993, leg. S. Becvar (8 exs. MTP, PMB) .

Description. TL 5.4–6.1 mm; MW 2.5–3.5 mm. Externally similar to the preceding species, but less convex and average size smaller.

Head reddish, with a very extended black area around the eyes and on the front, sometimes extended on the whole head surface. Mouthparts reddish, with last article of maxillary palpi dark; antennae reddish-yellow with last articles darkened apically.

Pronotum transverse, maximum width near the base. Sides almost straight, strongly bordered, posterior angles almost acute. Posterior border sinuate, angle between pronotum and elytra almost invisible. Surface covered by a close and fine punctuation, plus larger punctures, scattered mostly on the disc and on anterior and posterior borders.

Elytra oblong-oval, with maximum width near or just above the middle of the length, covered by a fine yellow pubescence. Longitudinal rows of punctures visible.

Dorsal colouration ( Fig. 39a–d): pronotum completely black, except for the lateral sides which are yellow, in some specimens a more or less developed reddish area on the disc is visible; elytron mostly dark with a more or less extended yellow humeral macula and smaller preapical spots.

Underside shiny, black. Prosternal process and distal portion of sternites reddish or pitch-brown. Surface covered by a dense and impressed punctuation. Reticulation hardly visible between the punctures. Sternites with a small apical comb of setae. Epipleuron reddish.

Legs reddish-brown, with pro and mesotarsi darkened. Metatarsal segments almost black. Metatibiae with a long row of setigerous punctures.

Male: Protarsi slightly dilated ( Fig. 39e). Anterior claws as in Fig. 39f: the inner is short and curved, acuminate, the outer is about twice longer, curved and apically flattened, spatula-shaped. Median lobe of aedeagus ( Fig. 39h): short and blunt, laterally sinuate in the apical third; parameres short ( Fig. 39g).

Female: Similar to male, often a bit duller. In some specimens (Baluchistan) lateral sides of pronotum are more rounded.

Variability. Quite variable in the development of dark pattern on elytra and pale colouration on lateral sides of pronotum. Different specimens studied from Oman (not types) share reduced yellow patterns on elytra, as illustrated in Fig. 39.

Distribution ( Fig. 52). Historical nomenclatural difficulties have complicated the interpretation of the distribution of this species. Its redefinition has been discussed by Wewalka (1974), giving characters for its diagnosis and extending its distribution to Iran. At present, the distribution of Nebrioporus mascatansis is certainly Oman (type locality), Southern Iran, Afghanistan and Pakistan (Baluchistan). The data for India (under the name of N. insignis ), considered doubtful by Zimmermann (1933), should be referred to what is now Pakistan, which would be the first records for this area.