Desmopachria andreae Megna & Sánchez-Fernández, 2014

Megna, Yoandri S. & Sánchez-Fernández, David, 2014, A new species of Desmopachria Babington (Coleoptera: Dytiscidae) from Cuba with a prediction of its geographic distribution and notes on other Cuban species of the genus, Zootaxa 3753 (6), pp. 585-596 : 587-592

Desmopachria andreae Megna & Sánchez-Fernández , sp. n.

( Figs. 1 , 6 a, 7–9)

Type material: Holotype male ( CZCTR): CUBA. Sancti Spíritus: Codina, 01–VII–10, Y. S. Megna leg. 21°54′42′′N, 80°03′36′′W, elevation ca. 891 m [printed], Holotype, Desmopachria andreae sp. n., Megna det. 2012 [red, printed]. Paratypes ( CZCTR if not stated otherwise): 6 males, 5 females, with same data as holotype. 1 male, CUBA: Sancti Spíritus: Salto del Caburní, 29–VI–10, Y. S. Megna leg. 21°55′17′′N, 80°00′20′′W, elevation ca. 520 m. 1 male, CUBA: Santiago de Cuba: Cabezadas del Río Cauto, 01–XII–2005, Y. S. Megna leg. 20°02′38′′N, 76°10′42′′W, elevation ca. 620 m. 2 males, 3 females, CUBA: Santiago de Cuba: El Olimpo, 04–VIII–2004, A. Deler-Hernández leg. 20°0′17′′N, 75°38′48′′W; 1 male, 1 female, CUBA: Santiago de Cuba: La Marsella, 02–XII– 2005, Y. S. Megna, leg. 20°00′4′′N, 76°13′06′′W, elevation ca. 370 m. 3 males, 1 female ( NMPC), CUBA: Santiago de Cuba: La Majagua, 14–VIII–2004, Y. S. Megna, leg. 19°57′38′′N, 76°52′32′′W. Each paratype is provided with its respective red label.

Description (male). Habitus ( Fig. 1 a). Body oval, broadly rounded in dorsal view; slightly flattened dorsoventrally; greatest width slightly anterior to midlength.

Measurements and ratios (minimun-maximun, mean), in mm (n=10): HL 0.2–0.3, 0.3; HW 0.7–0.8, 0.7; DBE 0.3–0.4, 0.3; PL 0.4–0.5, 0.5; PW 1.2–1.3, 1.2; PW/PL 0.3–0.4, 0.4; EL 1.2–1.5, 1.4; EW 1.3–1.4, 1.4; TL/EW 1.5–1.9, 1.6; TL 1.9–2.2, 2.1.

Color. Dorsally, head testaceous, darker posteriorly ( Fig. 1 a); pronotum testaceous, darker along posterior margin. Elytra testaceous, darker along the elytral suture and anterior margin ( Fig. 1 a); venter testaceous. Antennae and palpi yellow. Pro- and mesothoracic legs yellow; metathoracic legs brown.

Sculpture and punctation. Head inconspicuously punctate, clypeus indistinctly beaded; pronotum with rows of fine punctures along anterior margin, posteriorly with some fine sparse punctures, lateral bead of even width ( Fig. 1 a); elytron inconspicuously punctate. Venter without punctation.

Structure. Antenna with segments 1-2 wider than following segments; pronotum with posterolateral angles produced, rounded laterally and continuous in outline with elytra; elytra with apex rounded; convex in lateral view; prosternal process short, with apex acute, contacting metaventrite; metacoxal process without lateral lobe; abdomen with last ventrite rounded; protarsi and mesotarsi pentamerous without modification; metatarsal claws unequal.

Male genitalia. Median lobe with acute apex in dorsal view ( Fig. 1 b), in lateral view as in figure 1c. Parameres symmetrical, narrowing apically, with short setae on apex ( Fig. 1 d).

Female. Similar in habitus, vestiture and coloration to male, except lighter in colour.

Measurements and ratios (minimum-maximun, mean), in mm (n=10): HL 0.2–0.3, 0.3; HW 0.7–0.8, 0.7; DBE 0.3–0.4, 0.3; PL 0.4–0.5, 0.5; PW 1.1–1.3, 1.2; PW/PL 0.3–0.4, 0.4; EL 1.3–1.4, 1.3; EW 1.2–1.4, 1.3; TL/EW 1.5–1.8, 1.6; TL 2.0–2.2, 2.1.

Diagnosis. Adults of D. andreae can be readily distinguished from other species of the genus by the aedeagus, with the median lobe having an unsclerotized and acute apically ( Fig. 1 b); and parameres without a preapical, articulated process and the apex narrowing evenly ( Fig. 1 d).

Etymology. The new species is dedicated to Andrea Megna Alicio, mother of the first author, for her love. The species name is a noun in the genitive case.

Distribution. D. andreae has been recorded from localities in mountainous areas of the Sierra Maestra (Oriental region) and Guamuhaya (Central region) ( Fig. 6 a).

Ecology. According to Miller (2005) species of Desmopachri a can occupy a wide variety of habitats including ponds, streams, forest pools and phytotelmata. Specimens of D. andreae were collected in the backwaters of freshwaters with clear water and muddy-stony bottoms, located in highlands with little exposure to sun, with abundant cover vegetation but without aquatic vegetation ( Fig. 7 ).

Species distribution modelling. The predictive map for D. anderae shows a high suitability (red areas in Fig. 9 ) in a few areas of the Sierra Maestra (S-SW of Cuba), while other suitable areas are distributed in the south of the island, mainly in the mountainous areas and also in the Macizo de Guamuhaya (central part of Cuba). Our model also predicted that most of the study area has a low (<0.5) probability of presence (mainly in the western parts of Cuba; blue areas in Fig. 9 ).

The model achieved a 1.26 regularised gain value indicating good fit to presence data. The AUC was high, with a mean value of 0.94 for test data; i.e., values indicate an excellent predictive ability.

The analysis of single variable contribution ( Fig. 8 ) showed that mean temperature of the wettest quarter (63%), maximum temperature of the warmest month (10%) and altitude (10%) were the main factors influencing model performance. Mean temperature of the wettest quarter seems to provide more information by itself than the other variables, as derived from the Jackknife procedure ( Fig. 8 ).

Key to Desmopachria of Cuba

1 Parameres with apex deeply bifid ( Fig. 3 ) and with long apical setae; Jamaica, Hispaniola, Colombia, eastern Cuba ( Fig. 6 c)................................................................................ D. darlingtoni Young, 1989

- Parameres not deeply bifid, apical setae absent or very short; USA, Bahamas, Cuba................................. 2

2 Larger, TL> 1.9 mm; parameres without a preapical, articulated process ( Fig. 1 b); central and eastern parts of Cuba ( Fig. 6 a)....................................................................................... D. andreae sp. n.

- Smaller, TL <1.7 mm; parameres with a preapical, articulated process............................................ 3

3 Median lobe of aedeagus with a single tip and apex narrowed ( Fig. 2 ); USA, Bahamas, central part Cuba ( Fig. 6 b)........................................................................................... D. aspera Young, 1981

- Median lobe of aedeagus with two tips and apex expanded; Cuba................................................ 4

4 Median lobe of aedeagus expanded, bulbous at the base ( Fig. 4 ); body color usually uniformly dark brown; western part of Cuba ( Isla de la Juventud) ( Fig. 6 d).................................................... D. glabella Young, 1981

- Median lobe of aedeagus not expanded at the base ( Fig. 5 ); color reddish brown, with sutural margin of elytra darker brown; central and eastern parts of Cuba ( Fig. 6 e)............................................... D. tarda Spangler, 1973

Figures

FIGURE 6. Map of the known distribution of Desmopachria species in Cuba. a) D. andreae sp. n; b) D. aspera; c) D. darlingtoni; d) D. glabella; e) D. tarda. See Appendix 2 for additional information on the localities reported in each map.

FIGURE 7. Type locality of D. andreae sp. n. Codina (Cuba, Sancti Spíritus). Photo D. Leyva.

FIGURE 8. Representation of the contribution provided by the environmental variables considered to develop the MaxEnt model for D. andreae sp. n. Grey bars show the percent contribution of each variable to the model and corresponding values are given on the right axis. Jackknife results for the model (values on the left axis) are also shown for single variables (diagonal shade), for all variables except the one selected (black bars) and for all variables (white).

FIGURE 9. Maximum entropy model developed for D. andreae sp. n. in Cuba. Values range from high (red areas) to low environmental suitability (blue areas).

FIGURES 1 – 5. Desmopachria species from Cuba. 1) D. andreae sp. n. a) dorsal habitus; b) male genitalia, dorsal view; c) median lobe in right lateral view; d) right paramere, lateral view; 2 - 5) male genitalia, dorsal view; 2) D. aspera; 3) D. darlingtoni; 4) D. glabella; 5) D. tarda. Drawings of D. aspera and D. glabella are reproduced from Young (1981).