Paruroctonus coahuilanus Haradon 1985

Paruroctonus coahuilanus Haradon, 1985: 38, 41, fig. 27-30.
Paruroctonus coahuilanus:: Kovarík, 1998: 144; Sissom 2000: 514.

type(s):  Paruroctonus coahuilanus Haradon - Holotype male (adult) from México, Coahuila, Cuatro Cienegas basin, 14 August 1968 (S. C. Williams, M . A . Cazier, J. Bigelow). Depository: California Academy of Sciences (Type No . 15059).

ooriginal description:
Haradon, 1985: 38, 39, fig. 27-30

Description of holotype male. —Measurements: Table 4. Pigmentation: uniformly pale yellow, except fuscous markings about median ocular tubercle. Carapace: anterior margin protrudes slightly medially; surface granular; furrows and carinae well developed. Tergites: I-VII anterior elevated area smooth, posterior area finely granular in anterior half and coarsely granular in posterior half; median carina I-11 weak, III-VII moderately developed, granular; VII with two pairs granular lateral carinae. Sternites: III-VI very finely granular, VII finely granular with one pair weak lateral carinae. Chelicera: fixed digit without denticles on inferior carina; similar to P. williamsi and P. pecos (see Sissom and Francke 1981: figs 27-28, 31-32). Trichobothria typical of genus in number and distribution, as in P. williamsi and P. pecos (see Sissom and Francke 1981 :figs .13-26). Humerus: all carinae well developed, coarsely granular ; intercarinal surfaces lightly granular; macrosetae include one internal supramedial, two internal inframedials on proximal 3/5; four dorsals; three external medials on distal 3/5. Brachium: all carinae well developed, coarsely granular; intercarinal surfaces finely granular; four internal macrosetae. Chela: eight major carinae moderately developed; external carina irregularly and weakly granular, other carinae irregularly to moderately granular; intercarinal surfaces finely granular, moderately concave; supernumerary denticles well developed, six on fixed finger, seven on movable finger; primary denticles on fixed finger 3-2,4,5,5-6,6-7,13-12, movable finger 3,6-7,7,7,9-10,9-8; macrosetae include one long on internal carina, two on ventrointernal carina (proximal long, distal short), one long internal proximal on movable finger. Basitarsi I-III: moderately compressed laterally; superior setae on I six, irregularly distributed, on II 4+2, on III 6+2; mrs seta on I not clearly differentiated from superior setae, on II moderately off set from superior setae (Figs . 27-28), on III considerably offset (Figs . 29-30). Telotarsal setae I-IV: proinferiors 1,2,2,2; two each promedials, prosuperiors, retrosuperiors, retromedials; retroinferiors 1,1,2,2; retroinferior terminals 1,2,2,2. Ungues about 3/5 as long as telotarsus. Pectines extend to about mid-length of trochanter IV. Metasomal carinae: dorsals well developed, strongly crenulate; dorsolaterals I-IV strongly crenulate, V coarsely to moderately granular; laterals I crenulate, II-III with few posterior granules, IV obsolete, V present and granular anterior 1/4 only; ventrolaterals I-IV well developed, granular, V dentate; ventrals I-II moderately developed, lightly granular, III-IV well developed, granular, V dentate; intercarinal surfaces finely granular, except scattered coarser granules ventrally on V. Metasomal setae: all long; dorsals 1,1,1,2; dorsolaterals 2,3,3,3,; laterals 2,0,0,0,2; ventrolaterals 2,3,4,4,8; ventrals 3,3-4,4,5. Telson: smooth; 11 pairs ventral and lateral setae.

subsequent accounts:

Sissom and Hendrickson 2005:39 Key to the Vaejovid Scorpion Species of Northeastern México -  Dorsolateral carinae of metasoma more or less evenly denticulate throughout (i.e., without an enlarged terminal denticle); legs I–III with distinct retrolateral setal combs; Anterior margin of carapace almost straight; fixed cheliceral finger with ventral keelextending from tip to bicusp area; Pectinal tooth counts less than 24 in males and 17 in females; basitarsus of leg II with mrs seta; pedipalp chela fixed finger with 25–28 primary denticles (excluding proximal row) ...................................................................... Paruroctonus coahuilanus

distribution: NORTH AMERICA. México  (Known only from the Cuatro Cienegas basin, Coahuila). View Map

published records:  Paratypes. México: COAHUILA; Cuatro Cienegas basin, 14 August 1968 (S. C Williams, et al.), 12 males (CAS).

notes:   Haradon 1985 Diagnosis.—Female unknown. A species of subgenus Paruroctonus, stahnkei infragroup (cheliceral fixed digit with inferior carina extending proximally to level of bicusp; pectinal teeth 18-22 in males; pedipalp primary denticles excluding proximal row, 25-28 on fixed finger, 32-38 on movable finger; basitarsus II with mrs seta; dorsal metasomal setae I-IV 1,1,1,2), and williamsi microgroup (carapace length/cheliceral fixed digit length ratio 4.8-5.6; telotarsi II-IV with two retroinferior terminal setae; cheliceral fixed digit without denticles on inferior carina), differentiated by: basitarsus III (Figs. 29-30) with six distal plus two proximal (6+2) superior setae (occasionally 5+2 on one leg only).
Comparisons: P. williamsi and P. pecos differ in having four distal plus two proximal (4+2) superior setae on basitarsus III (Figs, 25-26); P. williamsi differs further in having 1,3,3,3 dorsal metasomal setae on I-IV.
Variation .—Total adult length 35-43 mm . Carapace length of adult males 4 .2-5 .1 mm. Pectinal teeth in males 18-22 (see Table 3) . Three specimens (out of 13) each had on one basitarsus III seven (five distal, two proximal) superior setae instead of the normal eight (6+2) . Pedipalp primary denticles (three specimens only), excluding proximal row, total on fixed finger 25-28, movable finger 32-38 . Metasomal setae : dorsals 1,1,1,2, except for an occasional loss; ventrolaterals I-IV normally 2,3,3,4 ; ventrolaterals V with seven to 10 (95% with eight or nine); ventrals normally 3,4,4,5, except for loss or presence of individual extraneous seta.
Etymology .— The name "coahuilanus" refers to the state of Coahuila.
Remarks.—The difference in fuscous pigmentation between P. williamsi and P. pecos reported by Sissom and Francke (1981: 107) appears to reflect a difference in intensity of a basically similar but highly variable pattern. The virtual absence of fuscosity in P. coahuilanus is very likely only a local edaphic characteristic and not of fundamental taxonorrlic importance (see P. gracilior Remarks above). Some males of P. pecos (CAS) from southern New Méxicoare very similar to P. coahuilanus in the development of the ventral metasomal carinae, and therefore any apparent distinction in this character that might be inferred from the description of P. pecos by Sissom and Francke (1981 :103) seems, rather, to be obscure. This character is subject to considerable sexual dimorphism in the williamsi and especially the borregoensis microgroups (i .e., males have well developed granular carinae, and females have weakly developed smooth carinae).
The three allopatric species constituting the williamsi microgroup are very similar, differing significantly only in the two diagnostic characters used to separate them, and possibly in the tendency of P. coahuilanus to have a longer mrs seta on basitarsus II (compare Figs . 23 and 27). Therefore, they might be regarded as subspecies of a single species . That they are currently isolated from one another is indicated by the fact that they have so far been found only in, and are probably restricted to, sand dunes . This would explain, also, why the less restricted species, P. gracilior, though sympatric with the williamsi microgroup and showing considerable local variation throughout that region, has remained, in contrast, a single species. The holotypes of P. williamsi and P. pecos (AMNH) and paratypes of each (OFF, WDS) were examined, in addition to the following P. coahuilanus material.