Vaejovis crumpi Ayrey et Soleglad, 2011

Ayrey, Richard F. & Soleglad, Michael E., 2011, A new species of Vaejovis from Prescott, Arizona (Scorpiones: Vaejovidae), Euscorpius 114 (111), pp. 1-15 : 5-13

Vaejovis crumpi Ayrey et Soleglad , sp. nov.

Figures 1–20; Table 1

Diagnosis: Small scorpion, 21–28 mm, color medium brown, lighter on the legs and telson with underlying mottling on carapace and mesosoma. Chelal palm large and bulbous on the male, chela length/width = 3.380 and chela length/depth = 3.117. Pedipalp movable finger with 7 ID denticles. Ventral surface of tarsomere II with single median row of spinules terminating distally with one spinule pair. Hemispermatophore with short bifurcated lamellar hook, distal crest on lamina terminus, and sclerotized mating plug with smooth barb. Carapace is shorter than the fifth metasomal segment. Pectinal tooth counts 11–13 (12) for the male, and 10–11 (11) for the female.

Distribution: Known only from the type locality, Prescott, Yavapai County, Arizona, USA. See map in Fig. 22.

Etymology: This species was named in honor of Darrell Crump for originally discovering the scorpions.

Type: Holotype male, Prescott , Yavapai County, Arizona, USA, 14 September 2009 ( R. F. Ayrey), specimen #251, deposited in California Academy of Sciences ( CAS).

MALE. Description based on holotype male except where noted. See Fig. 2 for dorsal and ventral views of a male paratype and Table 1 for measurements of holotype male and male and female paratypes.

COLORATION. Color is medium brown, lighter on the legs, telson orange. Underlying mottling on the carapace and mesosoma.

CARAPACE ( Fig. 5). Anterior margin of carapace moderately emarginated. Carapace moderately granular. Three lateral eyes on each side. Median furrow moderate and traverses entire length of carapace. Ratio of median eyes location from anterior edge/carapace length 0.326; carapace length/width at median eyes 1.394.

MESOSOMA ( Figs. 3, 6, 10, 19 paratype male and female). Tergites moderately granular with vestigial median carina on Tergites I– VI. Tergite VII with strong median carina on distal 2/3 and strong dorsal lateral and lateral supramedian granular carinae. Sternites III– VI finely granular and without carinae. Sternite VII with granular ventral lateral carinae on middle third. Presternites smooth. Sternite V posterior medial edge slightly swollen and whitish in color ( Fig. 19), more so than other sternites. Spiracles ovoid with median side rotated 35 degrees from posterior sternite margin. Sternites with variable number of microsetae.

STERNUM ( Fig. 13, 14, paratype female). Sternum conforms to type II, lateral lobes and apex subtly defined Sclerite is wider than long.

GENITAL OPERCULUM ( Fig. 13, 14, paratype female). Sclerites separated on most of length, genital papillae visible between sclerites at posterior edge. See comparison to female below.

PECTINES ( Fig. 13, 14, paratype female). All pectinal teeth, 12 in number, have exterodistal angling with large sensorial area. Middle lamellae 7/7. Fulcra are present. Each fulcrum with 1–3 central setae.

METASOMA ( Fig. 6). Segments I–IV: dorsolateral carinae strong and granular with distal denticle of I–IV enlarged and spinoid. Lateral supramedian carinae I–IV strong and granular with enlarged spinoid distal denticle. Lateral inframedian carinae moderately granular on segment I, posterior 3/4 of II, posterior 1/2 of III, and obsolete on IV. Ventrolateral carinae strong, granular. Ventral submedian carinae moderate, granular. Dorsal and lateral intercarinal spaces very finely granular. Segment I–IV ventral submedian setae 3/3. Segment V: Dorsolateral carinae strong, distally crenulate, basally granular. Lateromedian carinae strong, granular on basal 3/5, obsolete on distal 2/5. Ventrolateral carinae strong, granular. Ventromedian carina moderate, granular. Intercarinal spaces finely granular. Segment V ventrolateral setae 4/4.

TELSON ( Figs. 6, 12). Smooth with four pairs of large setae on the ventral surface, three large setae along both lateral edges of the vesicle and numerous smaller setae. Subaculear tubercle present but small. LAS present with 6-6 serrations.

CHELICERAE ( Fig. 11, paratype female). Dorsal edge of movable cheliceral finger with 2 subdistal (sd) denticles. Ventral edge is smooth, with well developed serrula on distal half.

PEDIPALP ( Figs. 7–9, 17, 4, female paratype). Femur. Dorsointernal carina serrated, dorsoexternal and ventrointernal crenulated, ventroexternal rounded. Patella. Dorsointernal carina serrated, ventrointernal crenulated, dorsoexternal and ventroexternal carinae granulated. Dorsal patellar ( DPS) and ventral patellar ( VPS) spurs formed with a pointed granule, DPSc carina well developed with 9 serrated granules. Chela. Digital (D1) carina weak, irregularly granulate, subdigital (D2) represented with a single rounded granule, dorsosecondary (D3) rounded with slight median granules, dorsomarginal (D4) round and smooth, dorsointernal (D5) rounded and irregularly granulated, ventroexternal ( V 1) and ventromedian ( V 2) carinae rounded and smooth, ventrointernal ( V 3) rounded, and external (E) carina weak to obsolete. Inner base of fixed finger with small raised area covered with 5 to 6 granules. Chelal finger median denticle ( MD) rows in straight line. Fixed finger median denticles ( MD) divided into 6 groups by 5 outer ( OD) denticles, and 6 ID denticles are found on the inner edge. Movable finger with 6 MD groups, 6 OD denticles and 7 ID denticles. Trichobothrial pattern type C orthobothriotaxic (see Figure 17). Chelal ib and it trichobothria located at fixed finger’s base, considerably proximal of sixth ID denticle; Dt on chela is proximal of palm midpoint; dt and dst are proximal to et and distal of est; patellar v 3 is located on external surface and positioned distally of et 3.

LEGS (Figs, 15, 16, paratype male). Ventral surface of tarsomere II with single median row of spinules terminating distally with one spinule pair.

HEMISPERMATOPHORE ( Fig. 18, paratype male). The hemispermatophore is lightly sclerotized with a somewhat centrally wide lamella that tapers distally. On the dorsal surface a distal crest is present on the inner distal aspect of the lamella, which is also visible from the ventral surface. The lamellar hook, which is highly sclerotized, is relatively short, emanating from the dorsal trough, and is widely bifurcated. The shortness of the lamellar hook is also indicated by comparing its length to the lamellar length, a ratio value of 0.288. Also, comparing the trough difference (i.e., the vertical distance between the ventral and dorsal troughs) to the lamellar hook length, a ratio of 0.774, indicates the hooks relative shortness. Due to the wide internomedian area of the lamella, a narrow non-conspicuous basal constriction is present. A weak, subtle truncal flexure is visible on the external aspect of the trunk/lamella juncture. A quite small slightly sclerotized mating plug was located on the ventral surface, on the internal area just below the ventral trough. Its stock is somewhat thick and the barb’s ventral edge is smooth.

Variability, male and female ( Figs. 13, 14, paratype female, 19). Pectinal teeth are longer and more angled in the male than in the female, the basal tooth is located closer to the pectinal base. Pectinal tooth counts are 11– 13 (12.09) (±0.47) [32] for the male and 10–11 (10.80) (±0.42) [10] for the female. The genital operculum is larger and longer in the male, the sclerites disconnected for most of their length, genital papillae protruding proximally. The genital operculum in the female is separated only on the proximal one-fifth. Posterior edge of sternite V expanded medially on the male ( Fig. 19). The metasomal segments are slightly thinner in the male, mean value differences of length to width ratios ranging from 0.8 % to 8.1 % (based on three males and females).

Dominant morphometrics, female/male ( Tab. 1). Comparing 351 possible ratios from 27 separate morphometrics between the female and male (three specimens each), the following morphometrics dominated for each gender: holotype male: chelal palm depth 26/0 and chelal palm width 25/1; paratype female: carapace length 26/0, chelal movable finger length 25/1, and chelal fixed finger length 24/2. These data imply that the male has a wider and deeper chelal palm whereas the female has a relatively longer carapace and longer chelal fingers. Maximizing on these data (i.e., using the most dominant morphometric per gender), six morphometric ratios show 20 % or greater MVD between these two genders, the carapace length / chelal depth = 24.1 %, the largest.

Type locality description. All of the type specimens were found on tributary washes of Lynx Creek , Prescott , Yavapai County, Arizona (N 34.5361°, W 112.3925°), at an elevation of 1688 m asl. The holotype male was found under a rock near the floor of a wash (see Fig. 1). Most of the specimens were found in leaf litter with a blacklight at night. The vegetation type is mesic Ponderosa Pine and mixed evergreen oak woodland (see Fig. 20). No other scorpions were found syntopically with V. crumpi , during 8 field trips to the area. Figure 20 shows a female with first instar juveniles. Figure 21 shows the locality of the holotype specimen .

Type material. Holotype: male, Prescott , Yavapai County, Arizona, USA, 14 September 2009 ( R. F. Ayrey) specimen #251, deposited in CAS . Paratypes (5 specimens): Prescott , Yavapai County, Arizona, USA, 14 September 2009 ( R. F. Ayrey), 2 males, 3 females ( RFA) .

Comparison to Related Species

The map in Fig. 22 shows the locality of the seven currently known Vaejovis species found in Arizona (type localities are indicated). We compare new species V. crumpi with all six species, five of these briefly, but concentrating specifically on species V. paysonensis , its closest relative.

Vaejovis vorhiesi , V. cashi , and V. deboerae : These species, occurring in the southeast corner of Arizona, roughly 180 miles from V. crumpi ’s locality, along with V. feti found in New Mexico, are referred to as the “sky island” species ( Graham, 2007; Ayrey, 2009). They are very closely related, exhibiting minor morphological differences, and all occupy their own unique mountain tops. However, they all exhibit only six inner denticles (ID) on the chelal movable finger, not seven which is commonly found in the vaejovids, including V. crumpi .

Vaejovis lapidicola : This species, one of Stahnke’s “inscrutable species”, was recently redescribed by Graham (2006) where a lectotype was declared and described. V. lapidicola has a very unique carapace, referred to as “planate (= flat)” by Graham (2007: 3). Its uniqueness, however, in our opinion, is its shape: the lateral sides from the proximal edge to the median eyes are subparallel, the carapace tapering abruptly from this point to the anterior edge (see Graham, 2007: figs. 1, 12). In contrast, the carapace in V. crumpi ( Fig. 5) tapers evenly from its proximal edge to the anterior edge. To quantify this difference in the two carapaces, we have constructed three morphometric ratios for two male type specimens: decrease in width from posterior edge to median eyes, 16.4 and 24.6 %, decrease in width from median eyes to the anterior edge, 39.3 and 29.8 %, and overall decrease in width from posterior edge to anterior edge, 49.3 and 47.1 %, for V. lapidicola and V. crumpi , respectively. From this data it is clear that in V. lapidicola , carapace tapers much less proximally than in V. crumpi (50 % difference) but increases in narrowing anteriorly (32 % difference) where the percentage of tapering is larger. The last ratio shows that the overall carapace tapering between the two species is essentially the same (only a 4.7 % difference), further emphasizing the abruptness of the anterior tapering of V. lapidicola . The carapace in V. lapidicola is longer than metasomal segment V (1.033) and pectinal teeth number is 14 in males, and 13 in females. In V. crumpi , the carapace is shorter than segment V (0.835, n = 3) and pectinal teeth number 12 in males, and 11 in females. Of particular interest is the close similarity of the hemispermatophore of these two species. Soleglad & Fet (2007: figs. 71–73) illustrated the hemispermatophore of three Vaejovis species, including V. lapidicola (fig. 71). Comparing the two hemispermatophores (see our Fig. 18) we see that both species exhibit a short bifurcated lamellar hook and a distal crest on the lamina terminus. Two morphometric ratios, lamellar hook length/lamina length and trough difference/lamellar hook length, are almost identical between the two species, showing only 1.4 and 0.1 % difference.

Vaejovis jonesi : This species is not well known, and has yet to be redescribed; though the type specimen exists and resides at the California Academy of Sciences (pers. comm. Vincent Lee, March 2011), the depository for the original Stahnke ASU collection. Therefore our comparison is based primarily on Stahnke’s (1940: 84– 86) original description in his unpublished PhD thesis, based on a adult female, as supplemented with presumably V. jonesi specimens available to us. V. jonesi is a larger species, roughly 50 % larger than V. crumpi . Stahnke provides measurements of the carapace (47 % larger), metasomal segments I (48.4% larger) and V (49.9 % larger), the telson (44.9 % larger), and the chelal movable finger length (45.5 % larger). These size differences are further endorsed by the pectinal tooth counts, V. jonesi female with 13 teeth and V. crumpi with 11 (a 18 % difference). Stahnke reports V. jonesi with two pairs of carinae on the seventh sternite whereas only the lateral carinal pair is present in V. crumpi ( Fig. 6). Finally, McWest (2001: fig. 241) reports that V. jonesi has two distal pairs of ventral spinules on the leg tarsus, while V. crumpi has a single pair ( Fig. 16).

Vaejovis paysonensis : We consider V. paysonensis the closest relative of V. crumpi . They agree in all major structural characteristics; i.e., chelal finger dentition, carapace shape and coloration, overall carination, pectinal tooth statistics, etc. However, by simple observation, it is clear that V. crumpi ’s chela palm in the male is noticeably globular, much more so than that exhibited in V. paysonensis . Consequently, we measured three male and female V. crumpi and a single male and female of V. paysonensis (the remaining specimens from the original set used to describe this species, Soleglad (1973)). From these eight morphometric sets, all possible morphometric ratio combinations were tested between Vaejovis crumpi , sp. nov., and V. paysonensis . 26 possible ratio combinations per morphometric value are possible. Table 1 shows the actual morphometric values of all eight specimens and Table 3 presents the key morphometric values that dominated in the ratio comparisons. We see a trend in this data: the chela, patella, and femur of V. crumpi are relatively wider than in V. paysonensis , where the widths dominated on an average of 21.88 tests out of 26. In V. paysonensis , 20.38 tests out of 26 dominated for these segments lengths (or fingers in the case of the chela). When these dominant value pairs are compared across the two species, we obtain ratio differences that are significant for the males in six ratios and for the females in two ratios (see Table 2). These ratio mean value differences ranged 12.6–27.3 % for the males and 11.8–18.5 % for the females. Another important dominant morphometric is the carapace length in V. paysonensis which dominated 25 and 23 tests for the male and female, respectively. In contrast, metasomal segment V length dominated in V. crumpi , 19 and 24 tests for the male and female, respectively. Combining the carapace length with metasomal segment V and the pedipalp patella and femur widths, we obtain, again, significant ratio differences between the two species, 19.8–23.8 % for the males and 11.1–16.3 % for the females. In all, thirteen morphometric ratios exhibited mean value differences of 12.6– 33.3 % for the male, and five ratios with differences of 11.1–18.5 % for the female. We hypothesize here that the male differences are more exaggerated due to the noticeable sexual dimorphism in the male V. crumpi whose chelae are noticeably inflated. This is quite apparent in Fig. 23 where the male chela of V. crumpi is compared to that of V. paysonensis .