Metophthalmus clarki, Andrews, Fred G., 2001

Andrews, Fred G., 2001, New Species Of Metophthalmus (Coleoptera: Latridiidae) With Notes On The Genus In The Baja California Peninsula, Mexico, The Coleopterists Bulletin 55 (2), pp. 129-133 : 131-133

Metophthalmus clarki new species

Figs. 4, 5, 6 Description. Length 1.0– 1.2 mm. Width 0.38–0.50 mm (n 5 27). Small. Body short, subparallel, humped in profile, glabrous. Cuticle shining, pale red­

dish brown. White chalky exudate covering dorsum of head, low profile areas of pronotum, apex and lateral margins of elytra and most of undersurface of body except legs and terminal abdominal segments. Head short; lateral longitudinal carina extending length of head, sigmoid, widest between eyes; median longitudinal carina extending posteriorly one­half of head length (measured from clypeal suture); dorsal surface between carina smooth without setae or puncta except narrow punctate channel interior to lateral longitudinal carina, short erect setae on carina dorsum. Lateral genal margin rounded, serrulate, extending laterally beyond lateral margin of eye by width of eye. Antennae 11­segmented, segments 3 to 8 short, transverse; segment 3 trapezoidal, widest basally; 3­segmented club abruptly formed; segments 9 and 10 tranverse; segment 11 quadrate, equal in length to 9 and 10 combined. Eyes 12 faceted. Tempora lacking. Pronotum wider than long by ratio of 100:65; lateral margin rounded, micro serrulate, 14–18 setose serrulations; dorsal surface smooth, without punctures or setation; except longitudinal carina that are reduced to two anterior and two posterior punctate nodes ( Fig. 4 ); pronotal cup reduced to slight depression between anterior nodes with few indistinct puncta ( Fig. 4 ); transverse groove distinct. Elytra 7­striate ( Fig. 6 ); sutural striae 15–17 punctate; punctures small, round, uniform size; interstriae straight, interstriae 3 and 5 raised, rounded; anterior humeral angle, small, tooth­like. Ventral surface mostly smooth, without punctures or setae. Mentum transverse, posteriorly notched, three transverse slits. Coxae round. Trochanters short, as long as wide. Mesocoxa narrowly separated, separation less than one­half procoxal width. Metasternum posteriorly with trough­shaped depression ( Fig 5 ); base of trough­shape contiguous with transverse depression on first abdominal sternite between metacoxa.

Type Series. Holotype. MEXICO: Baja California, 8 km. NW Santo Tomas, 200 m, IV­5­1985 / III­3­1986, W.H. Clark & P.E. Blom. Deposited in the California Academy of Sciences . Paratypes (69): Same data as holotype (26)[ CIDA] ; VIII­11­1982 / I­7­1984, (3) [ CIDA]; 8 km. NW Santo Tomas, Jct Hwy 1, 200 m , I­6­1982 / VIII­10­1982, W. H. Clark & P. E. Blom (6)[ CIDA] ; I­7­1985 / III­2­1986 (1) [ CIDA]; VIII­10­1982 / IX­4­1982 (5) [ CIDA]; I­7­1984 / III­2­1986, (1) [ CIDA]; VIII­30­1982 / I­7­1984 (2) ; III­9­1991 / VII­3­1991, W. H. Clark, et al. (3)[ CIDA] ; VI­22–1990 / III­9­1991, W. Clark & E. Clark (1)[ CIDA]; 9.7 km. E El Rosario, 140 m , II­7­1984 / IV­2­1985, W. H. Clark & P. E. Blom (1)[ CIDA]; 10.7 km. E El Rosario , 160 m , II­7­1984 / IV­2­1985, W. H. Clark & P. E. Blom (2)[ CIDA] ; IV­1­1985 / III­2­1986 (1) [ CIDA]; 11 km. air ENE El Rosario , 140 m , IV­1­1985 / III­2­1986, W. H. Clark & P. E. Blom (1)[ CIDA]; 12.7 km. E El Rosario , 180 m , IV­1­1985 / III­2­1986, W. H. Clark & P. E. Blom (2)[ CIDA] ; III­9­1991 / VII­18­1991, W. H. Clark, et al., (1)[ CIDA] ; VI­22­1990 / III­9­1991, W. H. Clark & E. M. Clark (1)[ CIDA]; 14.7 km. E El Rosario , 190 m , IV­1­1985 / III­2­1986, W. H. Clark & P. E Blom (10)[ CIDA] ; II­7­1984 / IV­2­1985 (1) [ CIDA]; VI­22­1990 / III­9­1991 , W. H. Clark & E. M. Clark (2)[ CIDA] . Paratypes deposited in the California State Collection of Arthropods, Albertson College of Idaho Collection and the Universidad Nacional Autonoma de Mexico .

Etymology. Named for William Clark, a tireless field biologist, who has contributed greatly to our knowledge of the natural history of Baja California.

Remarks. Metophthalmus clarki and M. septemstriatus are the only two Nearctic species with a seven striate elytron ( Andrews 1976). The complete internal longitudinal carina and heavy punctuation on the head of M. septemstriatus immediately separate it from M. clarki . Their distributions do not over­ lap, although M. septemstriatus does occur in mainland Mexico. Most collections of M. clarki have been along the coastal areas of northern Baja California extending along Mexico Highway 1 for approximately 100 miles; however, two collections are known from higher elevations in the Sierra de Juarez. Metophthalmus clarki and M. trux occurred together in all coastal collections, and M. rudis occurred together with M. clarki in the Santo Tomas area.

In addition to the two new species described above three species known only from the United States ( Andrews 1976) have been discoved from the Baja California Peninsula. They are know only from the northern one­half of the peninsula, but likely will be found in the southern one­half of the peninsula as additional Berlese sampling and Antifreeze pit fall trapping is conducted there. The Baja California distribution of these three species is provided below .

Figures

Figs. 4–9. Metophthalmus spp. 1) M. clarki, dorsal habitus; 2) M. clarki, ventral habitus; 3) M. clarki, oblique habitus; 4) M. trux, dorsal habitus; 5) M. haigi, dorsal habitus; 6) M. rudis, dorsal habitus.