Miradessus plaumanni (Gschwendtner, 1935) Miller & Benetti & Michat, 2023

Miller, Kelly B., Benetti, Cesar J. & Michat, Mariano C., 2023, Miradessus gen. nov. from South America described for two species previously in Amarodytes Regimbart, 1900 and two new species (Arthropoda, Insecta, Coleoptera, Adephaga, Dytiscidae, Hydroporinae, Bidessini), ZooKeys 1176, pp. 13-28 : 13

Miradessus plaumanni (Gschwendtner, 1935) comb. nov.

Figs 2 , 6 , 11 , 12 , 21-23 , 30

Amarodytes plaumanni Gschwendtner, 1935: 152; Young 1969: 2; Trémouilles 1995: 47; Nilsson and Hájek 2022: 101.

Bidessus plaumanni : Blackwelder 1944: 76.

Type locality.

Brazil, Santa Catarina State, Nova Teutônia.

Diagnosis.

This species differs considerably from the other known species in the genus. The anterior area of the dorsal surface of the head is testaceous in this species (Fig. 2 ), but pale yellow in the other species (Figs 1 , 3 , 4 ). The ventral portion of the male median lobe in M. plaumanni is broad and unilobate (Fig. 11 ) instead of strongly bilobate as in the other species (Figs 9 , 13 , 15 ). Other differences from other species in the group include: 1) lateral pronotal margins nearly straight posteriorly (Fig. 2 ) instead of broadly curved (Figs 1 , 3 , 4 ), 2) the pronotum and elytron different in color pattern (Fig. 2 ) from the other, more uniformly-patterned species (Figs 1 , 3 , 4 ), and 3) the lateral portions of the metaventrite and metacoxa more coarsely and densely punctate (Fig. 6 ) than in other species (Figs 5 , 7 , 8 ). The general shape and dorsal coloration of specimens are rather different as well (Figs 1-4 ).

Description.

Measurements. TL = 2.3 mm, GW = 1.2 mm, PW = 0.9 mm, HW = 0.7 mm, EW = 0.4 mm; TL/GW = 2.00, HW/EW = 1.7, FL/RL = 1.9.

Habitus. Body shape elongate-oval, lateral outline discontinuous between pronotum and elytron, posterior apex somewhat acuminate (Fig. 2 ).

Coloration (Fig. 2 ). Head brown with a narrow orange band along posterior margin. Pronotum yellow-orange with broad dark band along posterior margin and narrow band along lateral margins. Elytron maculate, yellow-orange and black, margins of maculae strongly demarcated; with transverse yellow-orange regions anteriorly, medially and apically, not extending to suture, with broad band of black along entire length of suture, margins of basal maculae posteriorly bilobed. Ventral surfaces mostly dark orange-brown; legs, epipleuron, and ventral areas of prothorax and head lighter orange-yellow, some sutural margins darker, infuscate, mesothoracic ventrites and prosternal process strongly infuscate.

Sculpture and structure. Head smooth, nearly impunctate, with small micropunctures sparsely distributed; eyes large (HW/EW = 1.7); antennae slender, unmodified. Pronotum with lateral margins moderately curved anteriorly, almost straight posteriorly; with narrow bead along entire margin; surface moderately punctate, punctures more concentrate along posterior margin; lateral pronotal plica strongly impressed, almost straight, extending more than 1/3 distance across pronotum. Elytron with lateral margin evenly and broadly rounded; surface finely and evenly punctate, with a slightly marked line of punctures with short setae extending medially from base to apex. Prosternum medially moderately broad, medially not protruberant, mediolateral surface somewhat granular; prosternal process moderately broad medially with slight tubercle, apical blade large, laterally with low rounded ridges along entire length, medially longitudinally shallowly sulcate, lateral margins almost straight to narrowly rounded apex (Fig. 6 ). Metaventer and metaventral wings smooth and shiny, covered with coarse, dense, and evenly impressed punctures. Metacoxa with medial portion moderately broad, metacoxal lines distinct, evenly divergent anteriorly to posterior margin of metaventer; lateral portion large, evenly covered with dense, coarse punctures; metatrochanter about 1/3 length of metafemur (Fig. 6 ). Abdominal ventrites finely punctured with fine setae.

Male genitalia. Median lobe in ventral aspect broad, with medial, dorsal elongate very slender, apically sharply pointed portion and ventral, broad, flattened, apically broadly rounded portion, dorsal portion slightly longer than ventral portion (Fig. 11 ); lateral lobe in lateral aspect robust, basal segment very broad, robust, apical segment short, robust, straight, apex broad, slightly bilobed (Fig. 12 ).

Sexual dimorphism and variation. Males have the pro- and mesotarsomeres I-III slightly but distinctly broader than in females.

Distribution.

This species is only known from the type locality, Brazil, Santa Catarina state, Nova Teutônia (Fig. 30 ).

Habitat.

Nothing is known of the habitat of this species.

Material examined.

Type specimens. Five syntype specimens are in OLML. One male specimen is labeled, " Brasilien S. Catharina 1934 [handwritten]/ Type Gschw [handwritten]/ Coll. Gschwendtner / Plaumanni Gsch. [handwritten] det. Gschwendtner / Type [red label]." This single specimen with the red type label is hereby designated as lectotype for the series (Figs 21-23 ). The other four specimens become paralectotypes and are mounted on two pins, two are labeled, " Brasilien, St Catharina 1934 [handwritten with black line border]/ Coll Gschwendtner/ Amarodytes plaumanni Gschw Det. Gschwendt. [first three words handwritten]/ Paratype Gschw [brown label with black line border]/ Paratype [handwritten, red label, lower right corner torn away]; other two labeled, " Brasilien, St Catharina 1934 [handwritten label with black line border]/ Amarodytes plaumanni Gschw Det. Gschwendt. [first three words handwritten]/ plaumanni Gschw. det. Gschwendtner [two of these labels]/ Coll. Gschwendnter [three of these labels]/ Paratype Gschw [brown label with black line border]/ Paratype [handwritten, red label]." No additional specimens were examined .

Figures

Figure 30. Miradessus species, distributions.

Figures 1 - 8. Miradessus species 1 - 4 dorsal habitus 1 M. beni 2 M. plaumanni 3 M. pulchellus 4 M. rikae 5 - 8 prosternal process left surfaces of metaventrite metacoxa metatrochanter and metafemur 5 Miradessus beni 6 M. plaumanni 7 M. pulchellus 8 M. rikae. Scale bars: 1.0 mm (1 - 4); 0.5 mm (5 - 8).

Figures 9 - 17. Miradessus species 9, 10 M. beni, male aedeagus 9 median lobe and left lateral lobe, dorsal aspect 10 right lateral lobe, right lateral aspect 11, 12 M. plaumanni, male aedeagus 11 median lobe and lateral lobes, dorsal aspect 12 right lateral lobe, right lateral aspect 13, 14 M. pulchellus, male aedeagus 13 median lobe and left lateral lobe, dorsal aspect 14 right lateral lobe, right lateral aspect 15, 16 M. rikae, male aedeagus 15 median lobe and lateral lobes, dorsal aspect 16 median lobe and right lateral lobe, right lateral aspect 17 M. pulchellus, female genitalia, ventral aspect. Scale bar: 0.25 mm.

Figures 18 - 29. Miradessus species, primary type specimens and labels 18 - 20 M. beni, holotype specimen 18 dorsal habitus 19 ventral habitus 20 specimen labels 21 - 23 M. plaumanni, lectotype specimen 21 dorsal habitus 22 ventral habitus 23 specimen labels 24 - 26 M. pulchellus, holotype specimen 24 dorsal habitus 25 ventral habitus 26 specimen labels 27 - 29 M. rikae, holotype specimen 27 dorsal habitus 28 ventral habitus 29 specimen labels. 21 - 23 courtesy of M. Schwarz (OLML) 24 - 26 courtesy of M. A. Balke (ZSMG).