Denticulobasis garrisoni sp. nov.

Figures 1, 3, 6, 7, 10, 11, 13, 15, 17, 22, 23, 88.

Etymology: Named after my colleague and friend Rosser W. Garrison, who collected the types in Rondônia and has helped me in the form of specimens and advice for over 20 years.

Type specimen: Holotype (3) and allotype (Ƥ). BRAZIL, Rondônia State: Rio Pardo and tributaries, ca 13 Km NW of Fazenda Rancho Grande, 62 Km SW of Ariquemes (10º50´S, 63º7´W), 187 m.; 5–10 November 1989, R.W. Garrison leg. (taken at ground level deep in forest in the company of Megapodagrion megalopus Selys, rare) (MNRJ). Paratypes: 2 3, same data as holotype (RWG); 1 3, same data as holotype (ABMM).

Description. Male holotype.

Head. Labium yellowish white. Labrum, base of mandibles, genae, and anteclypeus whitish yellow. Postclypeus olive. Antefrons and top of head brown with blue postocular spots (Fig. 101 d).

Thorax. Prothorax: laterally blue, dorsally orange yellow, except for the anterior lobe, which has an orange yellow spot surrounded by blue. Pterothorax: meso and metapleuron orange yellow with blue, antehumeral, mesepisternal, and metepimeral stripes. Legs yellow, wings hyaline, venation and pterostigma brown. Px in FW 11–12 in HW 10–11, R3 arising near Px 6 in FW and near 5 in HW. Petiolation distal to Ac by a distance ½ of its length in both wings.

Abdomen. S1, S2 and proximal part of S3 laterally blue, dorsally yellow; remaining part of S3, S4–6 laterally yellow, dorsally dark brown; S7 reddish brown with a black ring at mid-length, S8–9 dorso-laterally yellowish orange, cercus orange yellow, distal lobe whitish yellow.

Structural characters. Hind prothoracic lobe (Fig. 6) with a small lateral lobe, median lobe projecting caudally, semicircular, two-lipped; ventral lip continuous, dorsal lip disappearing antero-laterally. Mesepisternal horns (Fig. 6) with a basal and a distal portion, each one occupying about 1/2 horn's length; basal portion smooth and directed antero-laterally, distal portion transversally ridged like a screw and directed postero-laterally. Cercus in dorsal view (Fig. 13) subrectangular, about as wide at base as at the apex (excluding distal lobe), with a white, approximately rounded, basal membranous depression. Medial borders with a basal convexity and a distal concavity; a large whitish distal lobe present. After relaxing and spreading paraprocts, a digitiform transverse process directed medially is clearly visible in ventro-posterior and dorsal views (Figs 13, 17). Penis (Fig. 90) as in D. dunklei .

Dimensions (mm). Abdomen 27.8–31.4 (mean 30.2); HW 18.2-19-4 (mean 18.7).