A. M. Chickering.
The Male of Mecynometa globosa (O. P.-Cambridge) (Araneae, Argiopidae).
Psyche 70(3):180-183, 1963.

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THE MALE OF MECYNOMETA GLOBOSA
(0. P.-CAMBRIDGE) (ARANEAE, ARGIOPIDAE)* BY ARTHUR M. CHICKERING
Museum of Comparative Zoology
The female of this species was described from Guatemala by the elder Pickard-Cambridge in 1889. Apparently it was known only from that part of Central America until Dr. Petrunkevitch reported a female specimen from the Wilcox camp on the San Lorenzo River in Panama in 1925. Air. Banks reported two females from the Pan- ama Canal Zone in 1929. I now have in my collection about two dozen females from several localities in the Canal Zone and El Valle, Panama. Only three males have appeared in the collection and all were collected in 1934 and 1936. Mecynometa is an interesting genus with a total of seven species now known. Simon described a species from the African Congo; five species have been described from South America; M. globosu (0. P.-Cambridge) is now known from two countries in Central America. Because males have hitherto been unknown I have thought it worth while to describe one of these in this brief paper.
Mec~nometa globosa (0. P.-Cambridge), 1889 (Figures 1-5)
Meta globosa 0. P.-Cambridge, 1889
Argyroepeira globosa Keyserling, 1893
Mecynometa globosa Simon, 1894
hf. globosa F. P.-Cambridge, 1903
M. globosa Petrunkevitch, 1911
M. globosa Petrunkevitch, 1925
,M. globosa Banks, 1929
AT. globosa Roewer, 1942
M. globosa Bonnet, 1957
Male. Total length 2 mm.
Carapace about I mm. long; about .8
mm. wide between second and third coxae where it is widest; about .4 mm. tall; with median fovea a broad, shallow depression. Eyes. Eight in two rows. Viewed from above, anterior row strongly recurved; posterior row only slightly so. Viewed from in
front, anterior row almost straight; posterior row procurved, all measured by centers.
Central ocular quadrangle as wide in front as behind; longer than wide in ratio of about IT : 10. Ratio of eyes
AME :ALE : PAIE : PLE = 7.5 : 6 : 7 : 5. LE somewhat angu-
*Manuscript received by the editor January 8,1963. I 80




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Figs.
tibia of
male pa
behind.
1-5. External anatomy of Mecynometa globose. Fig. 1. Tarsus and left palp of male; dorsal view. Figs. 2-3. Two other views of same Ip. Figs. 4-5.
Epigyna from two different specimens; as viewed from lar. AME separated from one another by about their diameter, from ALE by slightly more than their radius. PME separated from one another by slightly less than their diameter, from PLE by their diame- ter. Height of clypeus equal to a little less than the diameter of AME. A long, slender spinule lies ventral to the interval between AXE and ALE on each side.
Chelicerae. Nearly vertical and parallel ; moderately robust ; basal segment about .8 mm. long; fang normal, regularly curved; fang groove with teeth but exact number and placement not determined because of fragility of specimen.
Maxillae. Parallel; fairly broad; quite normal in respect to the usual features; without special modifications. Lip. Much broader than long; strongly rebosdered; does not quite reach to middle of the maxillae.




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I 82 Psyche [September
Sternum. Broadly scutiform; broader than long in ratio of about 8 : 7; with numerous stiff bristles; not continued between fourth coxae which are separated by a little less than their width. Legs. 1234. Width of first patella at "knee" .I3 mm., tibial index of first leg 3. Width of fourth patella at "knee" .I I mm., tibial index of fourth leg 5.
Femora Patellae Tibiae Metatarsi Tarsi Totals (All measurements in mm.)
Legs well supplied with relatively long hairs. The few spines are long and slender. Some of the curled hairs on the fourth femora have been broken off but there appear to be two rows of eight or nine in each row; these are in longitudinal rather than oblique rows as seen in Leucauge and extend nearly throughout the proximal half of the prolateral surface of the segment.
Palp. Both patella and tibia are short as shown in the table above. The cymbium has three unusual spines, two near the distal end and one near middle. The most important features are shown in Figures 1-3.
Abdomen. About I mm. long; only slightly overlapping the carapace; about .8 mm. wide near posterior end where it is widest; about .8 mm. tall; closely resembles the abdomen of the female. Color in alcohol. Cephalothorax, legs, and mouth parts all yel- lowish white with variations. Grayish flecks occur on several parts but their distribution is too irregular for description. Abdomen: basically yellowish white; with many silvery flecks on the dorsolateral and lateral surfaces; the middorsal region is free from the silvery flecks; there is a relatively large silvery spot on each side on the posterior surface dorsal and lateral to the spinnerets, less conspicuous in the male than in the female but still distinctive; the whole pos- terior end is light grayish except for the silvery spots but is probably quite deeply colored in some males as in certain females in the col- lection; the venter is generally yellowish white with a conspicuous transverse spot near the middle which is composed of a group of bright stlvery flecks.
Female. The fang groove has three relatively robust teeth on the



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19631 Chickering - Mecynometa globosa 183 promargin; the retromargin has four teeth, the first of which is relatively large, the other three smaller. The curled hairs on the fourth femora appear to be arranged in two longitudinal rows with twelve in each row. Published figures of the epigynum differ con- siderably. This has led me to make a rather careful examination of these organs on several specimens. I have noted considerable difference in the appearance of this organ in different individuals. Perhaps these differences can be attributed to variations in internal tension and degree of chitinization and development following the process of moulting. Figures 4 and 5 illustrate differences noted in two females among specimens in my collection. Collection records. Both Pickard-Cambridges ( I 889-1 903) and Keyserling (1893) gave Guatemala as the locality for the original specimens. In addition to the specimens reported by Petrunkevitch ( 1925) and Banks ( 1929) as cited in the introduction to this paper I can now report collection of the species as follows: numerous females from Barro Colorado Island, Frijoles, and the Canal Zone Experiment Garden, all in the Canal Zone; four specimens from El Valle, Panama.
I also have a total of four males in the collection. One of these is from El Valle, Panama; the remaining three are from Barro Colorado Island, C. 2. The described male was taken in August, 1936. All specimens in my collection have been taken in July and August during my repeated collecting trips to the Canal Zone and other parts of Panama beginning in the summer of 1928. BANKS, NATHAN
1929. Spiders from Panama. Bull. Mus. Comp. 2001, 69: 53-96, 4 pis. BONNET, PIERRE
1957. Bibliographia Araneorum. 2. 3me partie. Toulouse : Les Artisans de I'Imprimerie Douladoure.
CAMBRIDGE, 0. P.-AND I?. P.-CAMBRIDGE
1889-1903. Arachnida-Araneida. In: Biologia Centrali-Americana. Du- lau & Co. London.
PETRUNKEVITCH, ALEXANDER
1925.
Arachnida from Panama. Trans. Conn. Acad. Arts and Sci,, 27: 5 1-248.
SIMON, EUGENE
1907. Arach. rec. par Fea sur la cote occid. dlAfrique I. Ann. Mus. Civ. Genova. 43 : 218-323, f. 1-3.




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