Saussurobolus Carl 1919 p. 389 New Synonymy
Centrelus Cook 1911 p.154 New Synonymy
Comanchelus Hoffman and Orcutt 1960 p.128 New Synonymy
Toltecolus Chamberlin 1943 p. 27 New Synonymy
Uvaldia Loomis 1968 p.499 New Synonymy
Mannobolus Loomis 1968 p.505 New Synonymy
Diagnosis: With characters of the family. Anterior gonopods: coxites with extended mesodistal processes rounded or angular. Coxites mostly quadrate in shape. Vinculum narrow at terminus, sub-triangular and partially fused with coxites. Lateral corners more narrow and not inserted like Atopetholus. Vinculum rising approximately half the length of the coxal apices. Posterior gonopods mostly curved and canoe shaped. Similar to
Arinolus, but coxal apices shorter and broader. Collum front margin curved from collum
182
Remarks: Generic differences were based largely on the presence or absence of
structures that have been observed to be variable, such as spinules. Authors such as Loomis (1968) have commented that certain species were being described in a particular genus, but could be pulled into another genus just as easily. When I looked at the species in aggregate, there is no denying they are closely related based on anterior and posterior gonopod morphology, pre-gonopodal legs, and collum shape. In particular the anterior gonopods are very similar – quadrate with a narrow vinculum. The posterior gonopods are canoe shaped or truncated canoe shaped. The spinules were observed on several specimens from the same samples of different species to be variable. All species have elongated lobes on the coxae of the third pair of legs. Until genetic data can be generated, I propose the oldest genus name, Eurelus be applied to all species in the genus and the other names be regarded as junior synonyms.
Distribution: Throughout Mexico, except the states of Veracruz, Tabasco, Chiapas, Campeche, Yucatan and Quintana Roo, southerneastern Arizona, central New Mexico and throughout west Texas, Sixteen species.
Key to the species of Eurelus
1a. Posterior gonopod telopodite canoe shaped with lateral margin fins... 2
183
2a. Posterior gonopod with telopodite distal end truncated ……… 3
2b. Posterior gonopod without telopodite distal end truncated ………..……… 8
3a. Posterior gonopod telopodite distal end appearing flat
with lateral margins expanded into pointed, sub-triangular
projections as in figure 182………...E. hubrichti Hoffman
3b. Posterior gonopod telopodite distal end with rounded
projections on the lateral margins, creating an irregular
appearance to the terminal end as in figure 250...……….E. soleatus Cook
4a. Posterior gonopod telopodite without sutureline visible near base of
telopodite……….……...……….5
4b. Posterior gonopod telopodite with suture line visible near base of telopodite
184
5a. Posterior gonopod telopodite without sub-basal solenomerite……...…...6
5b. Posterior gonopod telopodite with sub-basal solenomerite
as in figure 228…….…...…..…………..E. nietanus DeSaussure
6a. Posterior gonopod telopodite with rounded terminal end………....…………..….7
6b. Posterior gonopod telopodite with pointed terminal end
as in figure 234…………...…...…….E. nigrscens Chamberlin
7a. Posterior gonopod telopodite with emarginate lateral margin as in
figure 220………...…....………...E. neglectus Carl
7b. Posterior gonopod telopodite with terminal end curved proximad
185
8a. Posterior gonopod telopodite with terminal end pointe...……… 9
8b. Posterior gonopod telopodite with terminal end not pointed...……… 10
9a. Terminal end beak shaped as in figure 170………...E. chihuanus Chamberlin
9b. Terminal end rounded and cup shaped as in figure 204…... E. marisae n. sp.
10a. Posterior gonopod telopodite with a rounded terminal end
and lateral fins on one margin………...…. 11
10b. Posterior gonopod telopodite with lateral fins on both margins
a rounded terminal end as in figure 242..……..E. proximus Chamberlin
11a. Posterior gonopod telopodite with lateral fin and distal end
186
11b. Posterior gonopod distal marginwith an angular exapansion of the lateral margin
187 Eurelus alisonae, n. sp.
(Figs. 158 – 164)
Type: Male holotype from MEXICO, Nuevo Leon, 8.1 mi W. Iturbide, collected on 18
October 1965 by Ball-Whitehead (VMNH). Georeferenced coordinates: 24.720115°, - 100.028921°. Primary key: 1661.
Diagnosis: Posterior gonopod simple and canoe shaped curved with rounded terminal
end curved proximad. Similar to E. isaiasi but lacking suture on posterior gonopod telopodite. Differing from E. neglectus with posterior telopodite curved not bent and terminal end curved proximad. Differing from E. nietanus in the posterior telopodite lacking the sub-basal solenomere. Differing from E. nigrescens in the posterior telopodite broader, rounded and curved at the terminal end.
Etymology. The name is a noun in the genitive case. This species is named in honor of
my neice Alison Medrano.
Description: Male holotype 3.41 mm wide at the collum, 4.02 mm wide at segment 6/7,
3.7 mm wide at the epiproct. Ocelli: 45/45 (right/left) in a rounded patch. Several broken specimens in vial, no length measurement or segment count available. Color in alcohol light brown or tan mottled with reddish brown. Margins of pleurotergites yellowish in color. Collum with characters of the genus, posterior margin emarginate. No striations on
188
collum. Leg pairs 1 and 2 slightly incrassate. Coxal lobes on leg pair 3 elongated and strongly curved produced caudally to leg pair 6. Coxal lobes of leg pairs 4 through 6 sub- triangular and flattened. Coxal lobes of leg pair 7 quadrate and flattened. Anterior gonopods with characters of the genus. Posterior gonopod simple and canoe shaped curved with rounded terminal end curved proximad.
Additional Records. MEXICO: Nuevo Leon: 14.8 mi W. Linares on Rt. 60, 19 October
1965 by Ball-Whitehead (VMNH); MEXICO: Nuevo Leon: 8.1 mi W. Iturbide, 18 October 1965 by Ball-Whitehead (VMNH); MEXICO: Nuevo Leon: 10.2 mi E San Robarto jet, on rte 60, 20 October 1965 by Ball-Whitehead (VMNH); MEXICO:
Tamaulipas: 4.5 mi S. of Miquihuana, 16 February 1961 by R.O. Albert (FSCA). (Fig.