Vatellus caissara, Braga, Rafael Benzi & Ferreira-Jr, Nelson, 2016

Braga, Rafael Benzi & Ferreira-Jr, Nelson, 2016, Vatellini Sharp (Coleoptera, Dytiscidae) from Brazil: two new species, new records, and a checklist, Zootaxa 4111 (1), pp. 77-91 : 78-82

Vatellus caissara sp. nov.

( Figs 1–17 )

Type locality. Brazil, São Paulo State, Ubatuba Municipality.

Type material. Holotype: ♂ ( DZRJ 5800) “ Brasil, SP, Ubatuba Picinguaba, Poças no caminho para a casa da farinha, 29/V/2010, Ferreira-Jr N., Theberge R.D.” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr, DET. BRAGA R.B. 2014”; “Htipo” [red plastic label]; “5800” [blue plastic label]. Paratypes: 1 ex. ( DZRJ 5801) “ Brasil, SP, Ubatuba, Picinguaba, poça na estrada, 1/VI/ 2007, Ferreira-Jr. N., Pinto A., Braga R. B.” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5801” [blue plastic label]; 1 ex. ( DZRJ 5802) “ Brasil, SP, Ubatuba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, 07/VI/2008, N. Ferreira-Jr.” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5802” [blue plastic label]; 1 ex. ( DZRJ 5803) “ Brasil, SP, Ubatuba, Picinguaba, Poças no caminho para a casa da farinha, 29/V/2010, Ferreira-Jr N., Theberge R.D.” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5803” [blue plastic label]; 5 ex. ( DZRJ 5906) “ Brasil, SP, Ubatuba, Serra do Mar, Trilha do tronco, 30-31/V/2014, N. Ferreira Jr B. Aguiar” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014”; “Ptipo” [red plastic label] “5906” [blue plastic label]; 10 ex. ( DZRJ 5907) “ Brasil, SP, Ubatuba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, 22/VIII/2002, Ferreira-Jr. N.” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5907” [blue plastic label]; 12 ex. ( DZRJ 5908) “ Brasil, SP, Ubatuba, Picinguaba, Poça na Estrada, 31/V/2007, Ferreira-Jr N. Braga R. [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5908” [blue plastic label]; 1 ex. ( DZRJ 5909) “ Brasil, SP, Ubatuba, Picinguaba, trilha do tronco, 25/X/2004, Ferreira-Jr N. Braga R.B.” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5909” [blue plastic label]; 11 ex. ( DZRJ 5910) “ Brasil, SP, Ubatuba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, Poça na Estrada da casa da farinha, 29/VI/2006, N. Ferreira Jr & R.B. Braga” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5910” [blue plastic label]; 1 ex. ( DZRJ 5911) “ Brasil, SP, Ubatuba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, 04-08/XII/2002, Ferreira- Jr N.” [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5911” [blue plastic label]; 6 ex ( DZRJ 5915) “ Brasil, SP, Ubatuba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, 12/VI/2003, poças no caminho na casa da farinha, Alecrim V.P.”; [23°20’59,96”S 44°51’04,23”W] “ Vatellus caissara Braga e Ferreira-Jr., DET. BRAGA R.B. 2014” “Ptipo” [red plastic label] “5906” [blue plastic label].

Diagnosis. Medium size, habitus as in Fig. 1 . Dorsally brown, ventrally brown; legs bright brown. Ventral margin of male mesofemora with a brush of strongly developed setae. Speleum long, broad basally, apically rounded, apex concave in dorsal view, not strongly curved ( Fig. 14 ). Dorsoapical margin of lateral lobes of male genitalia, with area of dense, fine, elongate setae; curved setae present ( Fig. 10 ).

Description. (Based on holotype). Measures. Total length 5.60 mm; maximum width 2.75 mm; pronotum length 0.90 mm; elytral length 4.20 mm; maximum width of pronotum 1.76 mm.

Habitus ( Fig. 1 ). Body outline discontinuous in dorsal view; lateral elytral margins rounded; dorsoventrally moderately flattened.

Coloration ( Fig. 1 ). Dorsally brown. Ventrally brown, legs bright brown.

Sculpture and structure ( Figs 1–9 , 14 ). Head surface microreticulated, with fine punctation from clypeus to region between eyes, surface posterior to eyes without punctation; anterior clypeal margin distinctly produced; eyes relatively small, rounded. Pronotum densely punctate, surface between punctures microreticulated, punctures with short, fine, white setae; pronotum cordate with shagreened margins, transverse sulcus absent. Elytra densely punctuate as pronotum, surface between punctures microreticulate ( Fig. 2 ). Prosternum moderately short, setose; prosternal process broad, concave in midline, lateral margins rounded, apex narrowly pointed. Pro- and mesotarsomeres expanded ( Fig. 7 ); mesotrochanteres with incision bearing a brush of well developed setae; ventral margin of basal half of mesofemora with brush of strongly developed setae ( Fig. 4 ); metaventrite coarsely punctate, surface between punctures shiny, smooth; midline area ventrally produced; metacoxae with lateral portion relatively coarsely punctate, medial portion finely and densely punctate, metacoxal lines strongly divergent anteriorly, approximate posteriourly ( Fig. 3 ); metatrochanteres short, apically rounded ( Fig. 6 ), metatarsal claws finely dentate. Abdominal ventrites finely punctate laterally, surface smooth, shiny; ventrite VI flattened, apically rounded with sparse setae and apical lobe produced ( Fig. 9 ); speleum long, broad basally, sides convergent anteriorly, apically rounded, apex concave in dorsal view, not strongly curved ( Fig. 14 ).

Male genitalia ( Figs 10–13 ). Median lobe in lateral view evenly curved, narrowed apically, apex narrowly sharpened, without subapical setae, basal portion slightly broad, robust ( Fig. 12 ); in ventral view narrow, apically with lateral margins converging to sharp apex ( Figs 11, 13 ). Lateral lobes with apical portion narrow, parallel margins and rounded apex, dorsoapical margin with area of dense, fine, elongate setae; curved setae present ( Fig. 10 ).

Intraspecific variation. Small differences in size; total length 5.38–5.72 mm; maximum width 2.50–3.00 mm; pronotum length 0.88–0.94 mm; elytral length 4.00–4.20 mm; maximum width of pronotum 1.63–1.76 mm. In few specimens head and pronotum are lighter than elytra.

Sexual dimorphism. Male mesotrochanteres with incision bearing a brush of well developed setae; ventral margin of basal half of mesofemora with brush of strongly developed setae ( Fig. 4 ); in female incision on mesotrocantheres lacking, with weakly developed brush of setae; brush of setae on mesofemora weakly developed respect in male ( Fig. 5 ). Male pro- and mesotarsomeres thicker than in female ( Figs 7–8 ).

Female genitalia ( Figs 15–17 ). Gonocoxosternites very broad, robust, apical angle rounded, anterior margin concave, medial margin straight, anterior lobe long and slender ( Fig. 17 ). Gonocoxae elongate, very slender, almost straight, apex relatively narrowly rounded, apodeme elongate and slender ( Fig. 15 ). Receptacle spherical, of almost same size as spermatheca; spermatheca spherical, triangular process large, very broadly expanded ( Fig. 16 ).

Etymology. The specific name caissara refers to masculine and feminine noun “caiçara”, gentilic for the natives of the Coast of São Paulo state, the place of origin of the type material.

Taxonomic notes. This species can be distinguished from other members of the genus by the well-developed mesofemoral tuft of setae in males, and the shape of the speleum with an enlargement in the middle of its length. Vatellus caissara shares similarities with species of several of the clades defined by Miller (2005), therefore it was not possible to place it in a specific clade. In shape, gonocoxae and gonocoxosternites are similar as in V. grandis Buquet, 1840 and V. bifenestratus ( Zimmermann, 1921) but each gonocoxa has the anterior margin more concave and the medial margin straight instead of being concave as in the latter two species. The male lateral lobes have a tuft of stiff setae like V. drymetes Miller, 2005 , V. grandis and V. bifenestratus but the apical half is not so abruptly narrowed as in V. grandis and V. drymetes , and it has no parallel margins like in V. bifenestratus . Also the base in V. caissara is larger than in V. grandis and V. bifenestratus and is almost quadrangular whereas in the aforementioned species it is more rounded, while is pointed in V. drymetes . The median lobe is similar to that of V. tarsatus ( Laporte, 1835) , although the apex is more narrow.

Geographic distribution. So far known only from the São Paulo State in Brazil.

Figures

FIGURES 1 – 9. Vatellus caissara. 1. Dorsal habitus, 2. Dorsal punctation; 3. Metacoxal process; 4. Male left mesotrochanter and mesofemur, ventral view; 5. Female left mesotrochanter and mesofemur, ventral view; 6. Left metatrochanter and metafemur, ventral view; 7. Male left mesotarsus (a) and protarsus (b), ventral view; 8. Female left mesotarsus (a) and protarsus (b), ventral view; 9. Male ventrite VI, ventral view. Scales: Figs. 1 – 2 = 1.0 mm, Figs. 3 – 9 = 0.5 mm.

FIGURES 10 – 17. Vatellus caissara. 10 – 13. Male genitalia; 10. Right lateral lobe; 11. Median lobe, lateral view; 12. Detail of apex of median lobe, ventral view 13. Median lobe, ventral view; 14. Speleum and ventrites V and VI, dorsal view; 15 – 17 Female genitalia; 15. Spermatheca and associated structures, ventral view (a) and dorsal view (b); 16. Gonocoxae, ventral view; 17. Gonocoxosternites, ventral view. Scales: Figs. 10 – 13 and 15 – 17 = 0.1 mm, Fig. 14 = 0.5 mm.