Eremocosta, Roewer, 1934

Cushing, Paula E., Channiago, Felix & Brookhart, Jack O., 2018, Revision of the camel spider genus Eremocosta Roewer and a description of the female Eremocosta gigas Roewer (Arachnida, Solifugae), Zootaxa 4402 (3), pp. 443-466 : 464

Key to the species of Eremocosta

1 Fondal notch (male) deep and distinct ( Figs. 2I, K, S )....................................................... 2

- Fondal notch short and/or indistinct ( Figs. 2A, E, O, W )...................................................... 4

2 VDC (male) proximal on ventral edge of fixed finger ( Figs. 1C , 2I, J )................................. E. formidabilis

- VDC distal on ventral edge of fixed finger................................................................. 3

3 Male fixed finger dagger-like ( Fig. 2K ) with distinct MM and distinct tooth-like MD ( Fig. 2K , arrow). Female genital operculum as in Fig. 4C with wings tear-drop shaped......................................................... E. gigas

- Fixed finger not dagger-like, MM lacking or greatly reduced and MD present as a ridge ( Fig. 2S , arrow). Female genital operculum with straight, parallel, narrow anterior arms broadening into distinct, rounded club-shaped wings, shaped like hockey sticks ( Fig. 4E )................................................................................ E. striata

4 Male movable finger with quadrate MD ( Fig. 2O , arrow), female genital operculum as in Fig. 4D with recurved anterior arms and recurved posterior margins................................................................. E. gigasella

- Movable finger with no MD, female genital operculum not as above............................................. 5

5 Male fixed finger usually as long as or slightly longer than movable finger. Movable finger usually with two small MSM (sometimes only one) ( Fig. 2W ). Lower edge of VDC, when viewed from ectal side of chelicera, slightly concave ( Fig. 2W ). Female genital operculum with long straight anterior arms; posterior wings quadrate as in Fig. 4F. .............. E . titania

- Fixed finger usually slightly shorter than movable finger. Movable finger usually with just one small MSM ( Figs. 2A, 2E ). Lower edge of VDC, when viewed from ectal side of chelicera, slightly convex ( Figs. 2A, 2E ). Female genital operculum as in Figs. 4A or B........................................................................................ 6

6 Male movable finger with small but distinct MM ( Fig. 2E ). Female genital operculum club-shaped with long anterior arms and a posterior knob, posterior wing ovate as in Fig. 4B............................................... E . calexicensis

- Movable finger with barely visible MM (sometimes a tiny ridge) ( Fig. 2A ). Wings of genital operculum thin and curved as in Fig. 4A..................................................................................... E . bajaensis

Figures

FIGURE 1. VDC on the fixed finger of the right chelicera of male Eremocosta. Refer to Figure 2 for scale. A) Eremocosta bajaensis (holotype from CAS).B) Eremocosta calexicensis (holotype from USNM).C) Eremocosta formidabilis (IBUNAM). Note the more proximal locationof the VDC on the fixed finger of thisspecies.D) Eremocosta gigas (holotype from SMK).E) Eremocosta gigasella (DMNS ZA.35465). F) Eremocosta striata (DMNS ZA.21079). G) Eremocosta titania (DMNS ZA.15427).Arrows point to an internal carina in the VDC of some species.

FIGURE 2. Retrolateral (left) and prolateral (right) cheliceral views of the right chelicera of Eremocosta species. Scale bars = 1.0 mm. See text for collection abbreviations. A & B) Eremocosta bajaensis male (holotype from CAS). C & D) Eremocosta bajaensis female (IBUNAM). E & F) Eremocosta calexicensis male (holotype from USNM). G & H) Eremocosta calexicensis female (allotype from USNM). I & J) Eremocosta formidabilis male (IBUNAM). K & L) Eremocosta gigas male (holotype from SMK). M & N) Eremocosta gigas female (IBUNAM CNAN Sol00114). O &P) Eremocosta gigasella male (DMNS ZA.35465). Q & R) Eremocosta gigasella female (DMNS ZA.17350). S & T) Eremocosta striata male (DMNS ZA.21079). U & V) Eremocosta striata female (DMNS ZA.25451). W & X) Eremocosta titania male (DMNS ZA.15427). Y & Z) Eremocosta titania female (DMNS ZA.36256).Arrows in K, O, and S point to MD tooth (see text).

FIGURE 4. Genital opercula of females. Same specimens as illustrated in Fig. 2. Scale bars = 1.0 mm. A) Eremocosta bajaensis(IBUNAM).B) Eremocostacalexicensis (allotypefrom USNM).C) Eremocosta gigas (IBUNAM CNANSol00114). D) Eremocosta gigasella (DMNS ZA.17350). E) Eremocosta striata (DMNS ZA.25451). F) Eremocosta titania (DMNS ZA.36256).