Silpha lata Portevin, 1920

Silpha lata Portevin, 1920 View in CoL

( Figs. 4A–F View FIGURE 4 , 9F View FIGURE 9 , 10B View FIGURE 10 , 13B View FIGURE 13 , 15B View FIGURE 15 , 17F View FIGURE 17 , 18B View FIGURE 18 , 20F View FIGURE 20 , 21F View FIGURE 21 , 22–23)

Silpha lata Portevin, 1920: 396 View in CoL ( type locality: Ile de Nias (Malaisie) [probable misinterpretation of “Njasasee” or “ Lake Nyasa ”, recently Lake Malawi]).

Silpha capicola Pér. View in CoL : Portevin 1926: 72, 145 (misinterpretation of Silpha capicola Péringuey, 1888 View in CoL ).

Silpha capricola [sic] Péring.: Hatch 1928: 104 (partim, lapsus calami).

Type locality. Malaisie , Ile de Nias (probable misinterpretation of “Njasasee” or “ Lake Nyasa ”, recently Malawi, Lake Malawi) .

Type material ( 1 specimen). Tanzania: Holotype, ♂ ( MNHN) ( Fig. 4D View FIGURE 4 ), “ ILE DE NIAS | MALAISIE | COLL. LE MOULT [p] || TYPE [p, red label] || S. lata m. [hw, Portevin’s manuscript] || Muséum Paris [p] | coll. | Pic | Portevin [hw] [recent label added by curators] || Silpha | capicola | Pér. [hw] | R. Madge det. 197[p]0 [hw] || HOLOTYPE | Silpha lata Portevin, 1920 | D. Sommer & | J. Růžička des. 2023 [p, red label]”.

Additional material ( 8 specimens). Tanzania, Iringa Region , 1 ♂ ( NHMW) ( Figs. 4A–C View FIGURE 4 , 9F View FIGURE 9 , 20F View FIGURE 20 , 21F View FIGURE 21 ), Str. zw. Iringa u. Makumbaku [road between Iringa and Makambako], 1800 m, Changalawe — Mafinga, 29.xi.2009, A. Puchner lgt., ex coll. Barries. Njombe Region, 2 spec. ( HNHM) ( Figs. 4E–F View FIGURE 4 , 17F View FIGURE 17 , 18B View FIGURE 18 ), Dtsch. O. Af. [= German East Africa , SW Tanzania], Upangwa, [without date and collector’s name] ; 1 ♂ ( MNHN) ( Figs. 10B View FIGURE 10 , 13B View FIGURE 13 , 15B View FIGURE 15 ), same data, ex. coll. A. Grouvelle 1915; 1 ♂ 1 ♀ ( JSCC), Iringa — Njombe, 8.xii.1997, Werner & Lizler lgt .; 1 ♂ ( JSCC), near Njombe, 14.xii.1997, Werner & Lizler lgt . Revuma Region, 1 ♀ ( JSCC), Tanganyika-Terr., Matengo- Hochland, wsw. v. Songea, Litembo, 15[00]– 1700 m, 11.–28.ii.[19]36, Zerny lgt .

Ambiguous or poorly georeferrenced material ( 9 specimens). Tanzania, 3 spec. ( MNHN), Afr. or., Njassasee [= Malawi lake, without more details, but probably SW Tanzania], [without date and collector’s name], ex coll. A. Grouvelle 1915; 3 spec. ( HNHM), D. Ost-Africa [= German East Africa , without more details, but probably SW Tanzania], [without date and collector’s name] ; 3 spec. ( MNHN), same data, [coll.] Portevin, ex coll. M. Pic.

Redescription. Male ( ♂). Body ( Figs. 4A–D View FIGURE 4 ) oval, dorso-ventrally flattened. Elytra arched. Whole body surface and appendages dark brown to black.

Head ( Figs. 4A–D View FIGURE 4 ). Black, lustrous, surface with fine, very small, distinct, regular punctation. Covered with recumbent orange setation; dorsal surface without setation; lateral area posterior to clypeal suture covered with long, erect orange setation. Clypeus anteriorly widely notched. Anterior margin of clypeus with slightly irregular row of dense, long, orange setation. Eye kidney-shaped in lateral view. Frons with marked dorsal tentorial pits and a transverse, elevated crest posteriorly.

Antennae ( Figs. 4A–D View FIGURE 4 ). Medium-sized, with last four antennomeres forming a distinct club.

Pronotum ( Figs. 4A, C–D View FIGURE 4 ) moderately transverse, widest posteriorly. Margins rimmed anteriorly and laterally; anterior margin only slightly elevated and slightly sinuous; anterior margin slightly sinuous, without medial emargination; anterior angles weakly elevated. Posterior margin sinuous laterally. Surface dull, with fine punctation, punctures small, clearly separated, from disc to margin larger and more deeply impressed. Punctures without setae.

Scutellum ( Figs. 4A, D View FIGURE 4 ). Irregularly triangular, widely vaulted medially. Surface with fine, distinct, dense, homogenous punctation, from disc to margin smaller and slightly impressed; without setation. Posterior margin acute.

Elytra ( Figs. 4A, C–D View FIGURE 4 , 9F View FIGURE 9 ) subparallel, at the widest point (along 2/3 of its length) slightly wider than pronotum. Elytron with three elevated, rounded ridges; ridges nearly reaching apex of elytron; all ridges almost the same length. Elytral epipleura faintly elevated dorsally along almost the entire length, flattened at elytral apex. Apex of elytron widely rounded. Surface dull, without setation, with isodiametric microsculpture; covered with dense, distinct, regular punctation; punctures clearly separated by 2.0 or more of their diameter. Punctures posteriorly with small tubercle. Each tubercle bearing a small, short, black seta. Elytra with coarse, subrectangular punctures covering most of the surface in dorsal view. Elytral epipleura regularly, finely punctated to without punctation in ventral view.

Metathoracic wings. Apterous.

Ventrum ( Fig. 4B View FIGURE 4 ). Thorax finely punctate, covered rarely with short to medium-sized, recumbent, orange setae. Proventrite without punctation laterally; metaventrite rarely, roughly punctate, with dense, medium-sized setation. Mesocoxae closely separated. Abdominal ventrites with distinct impressions laterally in ventral view. Abdominal ventrites without punctation, covered with short, black setation, with expanded brick-wall pattern on intersegmental membranes.

Legs ( Figs. 4A–D View FIGURE 4 , 21F View FIGURE 21 ). Protarsus not expanded. Pro-, meso- and metatibia each with two apical spurs of different length. Metatibia almost straight, only very slightly curved in ventral view. Trochanters with bunch of medium-sized, orange setae.

Abdominal segments ( Figs. 13B View FIGURE 13 , 15B View FIGURE 15 ). Tergite VIII subquadrate, apically widely rounded, posteriorly rounded. Ventrite VIII apically and posteriorly widely rounded. Ventrite IX rectangular, apically almost straight, elongate and deeply medially desclerotized in ventral view. Spiculum gastrale robust, strongly elongate in ventral view; near the apex expanded.

Aedeagus ( Fig. 10B View FIGURE 10 ). Median lobe stout, robust, widely sinuous apex. Internal sac sclerotized. Parameres robust, curved downwards, shorter than median lobe, apex rounded. Basal portion oval, robust, as wide as median lobe.

Sexual dimorphism. Female ( ♀) ( Figs. 4E–F View FIGURE 4 , 17F View FIGURE 17 , 18B View FIGURE 18 ). Similar to male, except for the following structures. Protarsus not expanded. Apex of elytron rectangular (but rounded in the other species). Tergite VIII widely rounded. Ventrite VIII weakly rounded. Tergite IX elongate, rounded, in first half almost straight; tergite X widely rounded, almost pentagonal, apex with dense setation. Coxite robust, apex extremely elongated, acute; stylus extremely small, subquadrate, inserted laterally, shorter than apex of coxite.

Variability. Individuals vary in size and shape (see next paragraph). Elytra dark brown to black.

Measurements. TBL 15.6–17.5 mm in ♂ ( holotypus 15.6 mm) and 15.5–18.0 mm in ♀; MBW 10.0–11.0 mm in ♂ ( holotypus 10.5 mm) and 9.5–10.5 mm in ♀; RLWP 0.55–0.61 in ♂ ( holotypus 0.60), 0.55–0.63 in ♀; RLWE 0.96–1.10 in ♂ ( holotypus 0.96), 1.10–1.19 in ♀.

Differential diagnosis. Refer to species key and Table 3 below.

Distribution. An endemic species, known only from several localities in southern Tanzania (see map, Figs. 22–23 and Table 2).

Taxonomical remarks. Silpha lata Portevin, 1920 was described from “Ile de Nias [= Nias Island, Malaysia]”, based on a single male specimen ( Fig. 4D View FIGURE 4 ), erroneously listed as a female ( Portevin, 1920). It was compared with S. olivieri Bedel, 1887 , distributed in the Mediterranean subregion; also, a more comprehensive key to Silpha ( Portevin 1926) treated these two species as very similar, and placed them in a different part of the key from the Afrotropical species listed above. We have located the holotype in MHNH, and to our surprise, it is identical with the specimens from Tanzania identified as C. capicola by G. Portevin and also deposited in MHNH. The holotype was probably obtained from Eugène Henri Le Moult (1882–1965), a Paris insect trader ( Bousquet 2012: 733). Very probably, the German translation (“Njassasee”) of the Lake Nyassa (now Lake Malawi) was mistaken for Nias Island (“Ile de Nias” is clearly printed on the locality label). Consequently, the populations from Tanzania should be assigned to S. lata , and its distribution should be corrected to the Afrotropical Region.