Laccophilus spangleri Zimmerman 1970

Laccophilus spangleri
DIAGNOSIS. — Laccophilus spangleri can best be identified by the follow
LACCOPHILUS V THERMOPHILUS o ing combination of characters: irrorated pattern, lack of file in males or females, rakelike ovipositor, and the fifth front tarsal segment less than twice as long as the corresponding fourth. The rakelike ovipositor and lack of a file separates spangleri from most irrorated species, but it is easily confused with vacaensis and peregrinus. Its size is intermediate and overlaps with both species. The front tarsal segment of the males of vacaensis is more than twice as long as the corresponding fourth and helps to separate males, but females cannot be separated with complete assurance. Irroration in spangleri tends to be darker with more fusion of the individual dots. In specimens from Mexico the "fingers" that form the anterior part of the elytral pattern are more clearly defined and do not tend to fuse anteriorly, while in v. vacaensis there is considerable fusion with discrete "fingers" not really apparent. South of Mexica, this is not a reliable difference. The darkened area on the head and pronotum is more apparent in spangleri than in vacaensis.
L. proximus and L. fuscipennis, which are sympatric with spangleri in Veracruz and have similar patterns and color, have metacoxal files in the males and sawlike ovipositors in the females. L. peregrinus peregrinus has a similar aedeagus and ovipositor; but in Veracruz the elytral pattern is more uniform than
spangleri, and the average size is about 0.3 to 0.5 mm shorter (Tables 22, 24). DESCRIPTION. — Medium (length, 4.1 to 4.8 mm; width, 2.3 to 2.7 mm), brown, irrorated species; metacoxal file absent; prosternal process short; ovipositor rakelike. COLOR. Head: generally pale brownish-yellow tinged with red above and beneath except for some dark reddish-brown on the occiput between the eyes. Pronotum: pale yellowish-brown except anteriorly between the eyes; here darker color matches the darkened area of the head; some of the darker color trails weakly across the disc and the apex may be translucently reddish-brown. Elytra: heavily irrorated, reddish-brown pattern on yellow background; considerable coalescence of dots especially around margins of pattern; epipleura pale anteriorly and reddish-brown posteriorly. Tergite VIII: basally dark brown, but posterior half light yellowish-brown. Venter: variably light yellowish-brown with reddish tinge; front two pair of legs usually lighter than rest; sutures, coxal bases usually darkened. Genitalia: about the same color as venter. ANATOMY. Microreticulation: clearly double on much of the head and pronotum, but only weakly so on the elytra, especially in females; surface shining. Head: supraclypeal seam arching slightly upward at center above margin. Pronotum: WH/PW, 0.70; LP/PW, 0.40. Elytra: slight truncation of apices; female epipleura without flange. Venter: prosternal process with a median crest that nearly attains the anterior prosternal margin; postcoxal processes rounded, laterally projecting slightly posterior to the midline; last visible segment of males slightly truncated with produced apex and with an asymmetrical median crest; a small tuberosity near the left hind margin of the next to last ventral segment; last female segment not truncated, but nearly triangular; marginate groove on either side of the apex; both sexes with numerous setigerous punctures. Legs: proand mesotarsi enlarged in a dorsoventral plane; fifth tarsal segment of both legs about one and three-quarters as long as the corresponding fourth; palettes easily visible at 20 power magnification; profemoral setae (6 or 7) smaller and shorter than mesofemoral ones (6 to 8). Genitalia: oval plate with produced acuminate tip; its ventral crest curving slightly to the left as it extends anteriorly to near front margin; numerous raised lines of varying thickness on either side of the crest; aedeagus curving without noticeable angle; unevenly tapered to small knob at apex; ovipositor with about eight pairs of rakelike teeth.
VARIATION. — The elytral irroration varies in intensity and in the degree to which the dots tend to coalesce. In some specimens from Veracruz, the color is almost completely suffused with little evidence of irroration. South of Mexico there is much more spreading and fusing of the "fingers" so that the most anterior part of the pattern has a more solid appearance similar to that of vacaensis.
Females are slightly larger than males (Table 13, fig. 16), but there is almost complete overlap. There is no clear geographic trend in overall size, as seen by the similarity of means for the samples from La Tinaja, Veracruz, and from San Benito, Nicaragua. io -<t Wfl no "tf </->>/-> no >/-}
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— This species has been taken from several localities in northern and central Veracruz, from three localities on the south side of the Isthmus of Tehuantepec, and in Honduras and Nicaragua (fig. 15). Additional collecting will probably show that it occurs in most of the coastal regions of southern Mexico and Central America. It is a tropical lowland species. It seems to prefer temporary pools that are frequently subject to high surface temperatures, and that are located in clay soils. Holotype male, allotype female, five male, and five female paratypes with the following locality data are in the United States National Museum; Tehuantepec, Oaxaca, ix.2.63, J. R. Zimmerman. One male and one female paratype with the same locality data are also in each of the following collections: California Academy of Sciences, San Francisco, the University of Michigan Museum of Zoology, Ann Arbor, in the Departmento de Entomologia, Laboratorio de Sanidad Vegetal, Coyoacan, D. F., Mexico.
HONDURAS. — San Marcos Colon, 3 8, 2 2, vii.28.65, P. J. Spangler (USNM).
MEXICO. — OAXACA. Juchitan, 20 km. N., 3 <J, 2 5, ix.7.64; 3 m. E., 8 8, 33 2, ix.7.64; Tehuantepec, 26 <$, 23 2, ix.2.63, JRZ (NMSU). VERACRUZ. Cuitlahuac, 1 8, viii.25.62; near La Tinaja, 10 8, 8 2, viii.25.62; Paso de Ovejas, 10 8, 13 2, viii.27.62, JRZ (NMSU). Poza Rica, 2 8 , 1 2 , viii.27.65; Tantoyuca, 15 m. SE., 8 <J , 12 2, viii.28.65, P. J. Spangler (USNM).
NICARAGUA. — Esteli, 9 m. R, 14,5, 9 9, vii. 10.65; La Trinidad, 1 2, vii.27.65, P. J. Spangler; Rivas, 1 8 , vii. 3 1.67, O. S. Flint; San Benito, 13 m. N., 36 8, 28 2, vii. 11. 65; Somoto, 3 8, 5 2, vii. 11. 65, P. J. Spangler (USNM). This is a highly variable, polytypic species that ranges from Sinaloa and Veracruz, south to Panama, and probably into South America. It is composed of two races that are roughly separated by the Isthmus of Tehuantepec. The northern race, peregrinus, has two allopatric populations, which conceivably could be split even more into separate races; but lacking any character that could be demonstrated as consistently different between the two, they were retained as one. Veracruz populations have enough elytral pattern variation that some individuals with an irrorated pattern could readily be included in the west coast population. Others, however, have almost uniformly reddishbrown elytra and, hence, look quite different from the irrorated ones. The data from measurements are too incomplete to show much difference in the two populations and, in fact, show a close similarity when
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T OTAL LENGTH (mm) and L. fascipennis. Males are shown crosshatched; females, stippled.
compared to the values obtained for variabilis. The structure of the aedeagus supports retaining them as a single race, also.
The southern race, variabilis, has an even more heterogenous appearance than peregrinus. It varies from a black and yellow variegated form to one with nearly uniformly black elytra to one with a pattern which is found in typical peregrinus. The variation occurs in a north -south direction, so that the unlikely situation exists that individuals from Panama superficially most resemble those from Sinaloa. The quantitative data, however, show enough uniformity to suggest no great separation or differentiation of the different variabilis populations.
In this species elytral pattern has been less reliable for the recognition of intergrades than comparison of male aedeagi. In other species, L. maculosus and L. fasciatus for example, the pattern has frequently manifested intergrade features while the aedeagus did not. Only in a few instances were individual males found that had an aedeagus that clearly represented the intermediate condition. In L. peregrinus in Chiapas both races are represented as judged by elytral patterns. The southern race was taken in Ixtapa and nearby Chiapa de Corzo and the northern race in Comitan, which is about 90 miles closer to Guatemala. Other specimens of the southern variabilis were taken from three other localities in Oaxaca. None showed any intergradation in elytral pattern; but the males have unmistakenly intermediate aedeagi, and the aedeagi of the various Chiapas males are virtually identical.
Additional evidence for intergradation is found in the quantitative data.
The mean values for all four measurements for the Ixtapa and Chiapa de Corzo females are larger than for any of the other variabilis populations and approaches the value for typical peregrinus females (Table 14). In figure 18, 13 of the 18 largest individuals are females from Chiapas. Note that these females lie at about the mean value for p. peregrinus females (and males). This suggests that the larger size is due to gene flow from the northern race.