Desmopachria volatidisca Miller, 2000

Miller, Kelly B., 2001, Descriptions Of New Species Of Desmopachria Babington (Coleoptera: Dytiscidae: Hydroporinae: Hyphydrini) With A Reassessment Of The Subgenera And Species Groups And A Synopsis Of The Species, The Coleopterists Bulletin 55 (2), pp. 219-240 : 226-227

Desmopachria volatidisca Miller , new species

Figs. 11–13 , 18 Diagnosis. Distinguishable from other species by distinctive and complicated shape of male genitalia ( Figs. 11–13 ); median lobe very robust with

three pairs of apical rami ( Figs. 11–12 ); lateral lobe very broad in lateral aspect with apicoventral truncate process ( Fig. 13 ).

Description. Measurements. n = 10, TL = 1.57–1.74mm (x = 1.69 mm); GW = 1.05–1.16 mm (x = 1.13 mm); TL/GW = 1.48–1.53 (x = 1.50).

Habitus. Moderately sized for genus; rounded laterally in dorsal aspect, elongate oval; rounded laterally; greatest width slightly posterad of middle; rounded posteriorly; slightly flattened dorsoventrally; medium brown to yellow brown.

Coloration. Head and pronotum evenly yellow. Elytron brown to yellow brown, basally with poorly­defined yellow areas medially. Antennae and palpi yellow. Pro­ and mesothoracic legs yellow; metathoracic legs yellow­brown. All sterna yellow.

Sculpture and structure. Head finely punctate; clypeal margin anteriorly produced, strongly beaded; antennae short, antennomeres 6–10 anteroapically lobed. Pronotum evenly, finely punctate; lateral pronotal margins strongly rounded; lateral bead slightly expanded anteriorly. Elytron with punctation distinct, but fine and sparse, finer and less dense laterally and posteriorly; epipleuron narrow, very finely and inconspicuously punctate, punctures sparse. Prosternum very short, medially with posterior tubercle. Prosternal process broad medially, posteriorly acuminate. Metasternum impunctate. Metacoxae very finely and inconspicuously punctate. Abdominal sternite impunctate. Legs not unusually modified.

Male genitalia ( Figs. 11–13 ). Median lobe extremely complex, laterally and dorsoventrally very broad and robust, medially hollow; apically multi­lobate with very distinctive, posteriorly­directed rami, apex with flattened, laterally broad lobes ( Figs. 11–12 ). Lateral lobe in lateral aspect broad, apicoventrally with a pronounced, subrectangular projection, posterior surface with few, short setae ( Fig. 13 ).

Female genitalia ( Fig. 18 ). Spermatheca large, globular, spermathecal cap with large, distinctive anterior lobe; gonocoxae absent, apex of vagina with large, triangular, thickened membranous region; gonocoxosternites elongatetriangular, anterior lobe robust, anteriorly hooked, posterolateral margin of gonocoxosternite with region of short setae, apex with few, stout setae.

Variation. This species varies in color with some members laterally more lightly colored on the elytron. The basal elytral diffuse pale area varies in extent from nearly absent to rather broad.

Taxonomy. I have placed this species in the D. glabricula group (see Discussion below for clarification of group classification) since its median and lateral lobes are extremely robust ( Figs. 11–13 ).

Etymology. This species is named volatidisca from the Latin words, volatis, meaning ‘‘flying’’, and discus, meaning ‘‘saucer’’, in reference to the general shape of specimens (like small, spherical spaceships).

Natural History. This species was collected from a pool in a slow stream, a cattail marsh and an artificial cattle watering pond in the Bolivian lowlands.

Material Examined. Holotype: ϐ in MHNB, labeled, ‘‘ϐ/ BOLIVIA: Dpto Sta Cruz , Prov Velasco 2.5km SE San Ignacio, cattail marsh, 20 June 1999, K.B. Miller, colr./ 16°23'24̎ S 60°57'13 ̎W 325m #2–7 / HOLOTYPE Desmopachria volatidisca K.B. Miller, 2000 [red label with double black line bor­ der].’’ Paratypes: 1, same data as holotype; 6 labeled, ‘‘ BOLIVIA: Dpto Sta Cruz Prov. Velasco, 2.8 km SSW San Ignacio, marsh, 22 June 1999 / 16°24'11̎ S 60°58'26 ̎W, 383m #2–8/ PARATYPE Desmopachria volatidisca K.B. Miller, 2000 [blue label with black line border];’’ 1 labeled, ‘‘ BOLIVIA: Dpto Sta Cruz Prov. Chiquitos, 2.2 km E San Jose, artificial cattle watering pond, 26 June 1999 KB Miller, colr./ 17°51'00̎ S 60°43'02 ̎W 315m #2–12/ PARATYPE Desmopachria volatidisca K.B. Miller, 2000 [blue label with black line border];’’ 11 labeled, ‘‘ BOLIVIA: Dpto Sta Cruz Prov. Chiquitos, 2.7 km S San Jose, pool in stream, 27 June 1999 KB Miller, colr./ 17°52'20̎ S 60°44'28 ̎W 333m #2–15/ PARATYPE Desmopachria volatidisca K.B. Miller, 2000 [blue label with black line border];’’ 3 labeled, ‘‘ BOLIVIA: Dpto Sta Cruz Prov. Chiquitos, San Jose, mud puddle 28 June 1999 KB Miller, colr./ 17°50'52̎ S 60°44'16 ̎W 326m #2–16/ PARATYPE Desmopachria volatidisca K.B. Miller, 2000 [blue label with black line border];’’ 33 labeled, ‘‘ BOLIVIA: Prov Sta Cruz Prov. Chiquitos, 1.3 km WSW San Jose, pool in stream, 28 June 1999 KB Miller, colr./ 17°51'13̎ S 60°44'53 ̎W 320m #2–17/ PARATYPE Desmopachria volatidisca K.B. Miller, 2000 [blue label with black line bor­ der].’’

Figures

Figs. 2–14. Desmopachria spp., male genitalia. 2–4) D. amyae; 2) median lobe and left lateral lobe, dorsal aspect; 3) same, median lobe, right lateral aspect; 4) same, right lateral lobe, right lateral aspect; 5–7) D. challeti; 5) median lobe and left lateral lobe, dorsal aspect; 6) same, median lobe, right lateral aspect; 7) same, left lateral lobe, left lateral aspect; 8–10) D. signatoides; 8) median lobe and left lateral lobe, dorsal aspect; 9) same, median lobe, right lateral aspect; 10) same, right lateral lobe, right lateral aspect; 11–13) D. volatidisca; 11) median lobe, dorsal aspect; 12) same, median lobe, right lateral aspect; 13) same, right lateral lobe, right lateral aspect; 14) Desmopachria signatoides, left antenna, dorsal aspect. bars = 0.1 mm

Figs. 15–20. 15–16) D. amyae, female genitalia; 15) right gonocoxosternite; 16) same, right gonocoxa; 17–20) Desmopachria species, female genitalia, ventral aspect; 17) D. challeti; 18) D. volatidisca; 19) D. convexa; 20) D. youngi; al = anterior lobe of gonocoxosternite, bc = bursa copulatrix, co = common oviduct, ds = spermathecal disc, fd = fertilization duct, fs = fertilization sac, gc = gonocoxa, gs = gonocoxosternite, ra = ramus, sd = spermathecal duct, sp = spermatheca, va = vagina. bars = 0.1 mm.