Laccophilus vacaensis vacaensis Young 1953

Laccophilus vacaensis vacaensis Young Laccophilus vacaensis Young, 1953a, pp. 31-34. Holotype: University of Michigan Museum of Zoology, male; near Marathon, Vaca Key, Florida, viii.22.49, J. S. Haeger and F. N. Young; Young, 1954, p. 46; Young, 1963, p. 5.
DIAGNOSIS. — L. v. vacaensis has an irrorated pattern and color similar to a dozen other species of North American Laccophilus, but possesses structural characters in both males and females that permit comparatively easy identification. The males have the fifth segment of the two front pair of tarsi more than two and a quarter times as long as the corresponding fourth. Other species do not exceed twice the length. Females have a crease, immediately above the epipleuron, that extends nearly two-thirds the length of the elytron. The presence of this crease seems to be directly related to the longer tarsal segment of the males. The distance from the ventral margin of the epipleuron to the crease is about the same as the length of the fifth tarsal segment, so this is probably an adaptive feature to assist the male to grasp the female for copulation.
L. v. vacaensis is most likely to be confused with the sympatric species, L. proximus and L. spangleri. In the first case, the lack of a file in the male and the presence of a forklike, instead of sawlike, ovipositor in the female will assist — along with the characters given above. L. spangleri can be best separated by the male shorter fifth tarsal segment or by the weaker crease on the female elytra and by the male aedeagus. VARIATION. — The degree of pigmentation of the pronotum and of the elytral pattern varies considerably in this race. Specimens from Yucatan and Central America are much darker than those from Texas and the east coast of Mexico, with the individual dots of the pattern tending to form more continuous chains of five or six dots. A few specimens tend to be dark enough to suggest suffusion of pigment rather than irroration. Central American specimens have a prominent darkened area on the anterior margin of the pronotum between the eyes, while those from farther north may have only a faint suggestion of reddish-brown or brown color.
Males appear to average 0.05 to 0.10 mm larger than females, but the largest specimen examined was a female (fig. 16). There seems to be a geographical difference in size, since the specimens from Guatemala and Costa Rica (especially the latter) are almost 0.1 mm larger than those from south Texas and almost 0.25 mm larger than those from Progreso, Yucatan. There are too few samples to decide whether the difference in size is racial, clinal, or local. — The range of this race is a wide one and a perplexing one. It was first described from a single locality from the Florida Keys and is now known to occur on several Caribbean Islands as well. It should occur clear around the Gulf of Mexico, but it has not been reported from Alabama or Mississippi. It is found in lowlands of Central America (fig. 15). This part of its distribution is entirely logical, if one assumes that it occurs in temporary pools and ponds that are often subject to temperatures above 40° C; but the rest of the distribution is more difficult to explain; making it appear that another unrecognized race is involved. It has been collected from several localities at 5000 feet or above in Morelos, Jalisco, Sonora, and Arizona. It would thus be expected that these populations should be closer to v. chihuahuae, which more typically occurs at the higher elevations; but they Young ( 1953a) collected vacaensis in a small freshwater pool in which the principal vegetation was Chara. The pool was drying up, the surface was unshaded, and the noon temperature of the surface water may have exceeded 40° C. I have collected a large number of specimens from what may have been a brackish temporary pool about a mile inland from an extensive mangrove swamp near Progreso,
Yucatan. The water was very dark, only a few inches deep, and filled with debris, but had some emergent, grassy vegetation. Interestingly enough, vacaensis was taken in association with L. quadrilineatus mayae and Young (1963 ) also described vacaensis as being in association with L. inagua Young in the Bahamas. L. inagua most resembles q. mayae among North American and West Indian Laccophilus. UNITED STATES OF AMERICA. — ARIZONA. Santa Cruz County. Pena Blanca, Pajarito Mts., 2 8, 1 2, vii.19.62, Arnett and Van Tassel (CUA). LOUISIANA. Cameron County. Cameron, 1 9, vii. 10-14.05, Van Dyke? (CAS). TEXAS. Bastrop County. 1 2, vii.13.37 (TAM) . Cameron County. Brownsville, 3, vi.— .— ; 16, — .— .— (USNM); 1 8, ii.24.96, H. F. Wickham (AMNH); 1 2, x.— .42, E. S. Ross (CAS); 1 8, ii.— .— , Wickham (ANSP); 1 8, Wickham (MCZ). Port Isabel, 1 8, 7 2, x.20.49, O. Bryant (CAS). Hidalgo County. Edinburg, 1, ii.24.36, J. G. Needham (CNL). Kleberg County. Kingsville, 4, —.—.—, C. T. Reed (CNL); 1 2, x.20.61, B. McDaniels; 1 8, xi.5.59 (USNM). Victoria County. Victoria, 3, ix.18.14, J. D. Mitchell (USNM); 1, ix.22.14 (USNM).
BRITISH WEST INDIES. — BAHAMAS. Great Inagua Is., Matthewtown, 8 8,1 2, i. 3 1.53, L. Giovannoli & E. B. Hayden; New Providence Is., Nassau, 1 2, iv.5.53, E. B. Hayden (AMNH).
CUBA. — Santiago, Vista Alegra, 1, vi. 16.42, C. T. Randall (USNM). HAITI. — Attelye, 1 8, 1 2, x.22.25, W. A. Hoffman (USNM). COSTA RICA. — Bagaces, 2 8, 2 2, vii. 12.57, D. R. Lauck; La Cruz, 16 m. S., 100 +, vii.25.63; Liberia, 12 m. SW., 1 8, vii.25.65; 5 m. SW., 22 8, 31 2, vii.24.65, P. J. Spangler (USNM).
GUATEMALA. — Aldea lesus Maria, 6 $, 6 2, viii.15.65, P. J. Spangler MEXICO. — CAMPECHE. Champoton, 11 m. SW., 1 8, ix.27.63, JRZ (NMSU ) . JALISCO. Guadalajara, 1 1 m. S., 2 8 , 1 2 , vii.30.62, JRZ (NMSU) . Jiquilpan, 15-20 m. W., 1 8, xi.30.48, E. S. Ross (CAS). Near Cuautla, 1 2, 3 2, viii.28.62; Puente de Ixtla, 1 2, viii.29.62, JRZ (NMSU). SINALOA. Mazatlan, 2 8, viii.1.62; 1 2, xii. 11.62, JRZ (NMSU). SONORA. . Aribabi (E. of Moctezuma), 2 8, xii.15.62, JRZ (NMSU). Naco, 1 2, viii.15.49, G. M. Bradt (AMNH). TAMAULIPAS. Llera, 20 m. S., 1 8, iii.24.63, JRZ (NMSU). Matamoros, 15 m. S., 1 8, vi.10.60, F. N. Young (UMMZ). YUCATAN. Progreso, 5 m. S., 128 8 , 229 2, xi.24.63, JRZ (NMSU).