Zapotecanillus nanus, Sokolov, Igor M., 2013

Sokolov, Igor M., 2013, A new genus and eight new species of the subtribe Anillina (Carabidae, Trechinae, Bembidiini) from Mexico, with a cladistic analysis and some notes on the evolution of the genus, ZooKeys 352, pp. 51-92 : 59-61

Zapotecanillus nanus sp. n. Figs 19, 20, 25, 39-41, 61, 69, 73, 77, 90-92, 94

Type material.

HOLOTYPE, male, in NMNH, point-mounted, labeled: \ MEX. Oax., 15mi. S. Valle Nacional, 4000' 21.V.1971 S.Peck Ber.204, leaf litter \ Borrowed Ex. J.M. Campbell \ USNMNH 2051867\. PARATYPES (27 ex., 4♂4♀ were dissected), 4 ex. labeled same as holotype, except one specimen, which has an additional label: \ Geocharidius n. sp. det. T.L.Erwin 76\, where italicized font means handwriting.; 12 ex. labeled: MEXICO: Oaxaca, 15mi. S. Valle Nacional, 4000' 21 May 1971, leaf litter, S. Peck \ THOMAS C. BARR COLLECTION 2011 Acc. No. 38014\; 1 ex. labeled: \ MEXICO: Oaxaca 15.1mi S Valle Nacional 4300' VIII-11-18-1973 \ under bark hardwood A.Newton \ Borrowed ex. MCZ \ Loan from USNMNH 2051867\; 10 ex. labeled: \ MEXICO. Oaxaca 18.7mi S Valle Nacional 5200' 17 Aug.1973\ A.Newton Collector \ Loan from USNMNH 2051867\ (deposited in CAS, CMNH, NMNH).

Specific epithet.

The specific epithet is a Latin adjective, nanus, in the masculine form, meaning dwarf, miniature, and refers to the small size of the beetles.

Type locality.

Mexico, Oaxaca, 15mi S from Valle Nacional.

Recognition.

Adults of this new species are distinguished from those of other species of the genus by the combination of small size and brunneorufous color; and males can be further distinguished by the shape of the median lobe (Fig. 39).

Description.

Size. Small for genus (SBL range 1.02-1.16 mm, mean 1.10 ± 0.049 mm, n=12).

Habitus. Body form (Fig. 25) moderately convex, slightly elongate (WE/SBL 0.41 ± 0.09), head of normal proportions for genus (WH/WPm 0.75 ± 0.016), pronotum narrow compared to elytra (WPm/WE 0.75 ± 0.028).

Color. Body monocolorous, brunneorufous, appendages testaceous.

Microsculpture. Microlines partially effaced on disc of pronotum.

Prothorax. Pronotum relatively long (LP/LE 0.43 ± 0.020) and moderately transverse (WPm/LP 1.26 ± 0.030), with margins straight and markedly constricted posteriorly (WPm/WPp 1.38 ± 0.044). Basal margin slightly oblique laterally. Posterior angles small, contour of posterior angles obtuse (112-126°) without or with 1 small denticle in front of the angles.

Elytra. Slightly convex, not depressed along suture, comparatively wide (WE/LE 0.72 ± 0.025). Margins rounded, moderately divergent in basal half, evenly rounded to apex in apical third, maximal width of elytra slightly behind the midpoint.

Legs. 1st male protarsomere markedly dilated apico-laterally (Fig. 20).

Male genitalia. Median lobe of aedeagus (Fig. 39), with small, slightly elongated apex, angulately rounded at tip. Dorsal plate 1 long, with apical pointed attenuation of moderate length. Dorsal plate 2 joined to plate 1 at its middle ventrally, where it forms a distinct protuberance. Ventral sclerites with sides divergent ventrally, trianguloid in shape. Right paramere short and moderately narrow (Fig. 41). Left paramere with distinct apical constriction (Fig. 40). Ring sclerite with long handle-like extension, pointed apically (Fig. 61).

Female genitalia. Gonocoxite 2 comparatively short, with slightly curved blade and narrowly rounded apex (Fig. 69). Laterotergite with 5-6 setae. Spermatheca standard for genus (Fig. 73).

Geographical distribution.

The species is known from a few localities in the Sierra de Juárez Range, a part of the Sierra Madre de Oaxaca, along the ~5km stretch of the Rio de Valle Nacional (Figs 77 and 94, white triangles).

Way of life.

According to the label data, the elevations of localities range from 4000' to 5200' (1200-1600 m).

Relationships.

Aedeagal characters (shape of dorsal plates and left paramere) suggest that Zapotecanillus nanus is most closely related to the sympatric Zapotecanillus oaxacanus . See also Fig. 90 for cladistic affinities.