Eremobates angustus species group

Diagnosis:

Muma (1951) recognized this species group as including two species: Eremobates anugustus Muma 1951 and Eremobates cruzi Muma 1951. Per his original definition of the group (Muma 1951), males have a constriction but no distinct notch at the base of the fixed finger (Fig. 1) when viewed from a dorsal aspect, no ectodorsal process (flange) is present, and the mesoventral groove of the fixed finger is not dilated basally (Fig. 2). Males, he noted, are not usually provided with ctenidia on the first postspiracular abdominal sternite, and females have roughly triangular opercula that are adjacent but are prolonged laterobasally. He reported that both rows of fondal teeth are graded in size I, III, II, IV, although he later (Muma 1986, 1987) suggested that fondal tooth formulae are not valid for genus or group separation, as they are subject to wear, especially by females. Muma (1986) also added a third species (Eremobates becki Muma 1986) to the group. Monophyly of the group has not been tested, and its relationship to other Eremobates species groups as not been established.


Literature accounts:


Muma 1989: 6-7 (key):

(Male) Mesal groove of fixed chelicera! finger mesoventral in position...........................
Mesal groove narrow apically, occupying less than half of finger width...........................
Mesal groove not dilated basally ............................................................. angustus group


(Female) Opercula not or only moderately separated posteriorly; broadly triangular in shape and without distinct pits midway along ectal margins except for E. mimbrenus new species................................................................................................................................
Mesal margins of opercula straight or evenly curved to the posteriomesal notch............
Mesal margins of opercula divergent both anteriorly and posteriorly ......angustus group


Notes:



Included species


  • Eremobates angustus Muma 1951
  • Eremobates becki Muma 1986
  • Eremobates cruzi Muma 1951

Distribution:


 


Key to species (males):


Fondal notch quadrangular, slightly wider than long, only slightly narrower or wider than the fixed finger (Fig. 3); anterior tooth of movable finger low, flattened; metatarsus of palpus with or without scopula....................................................................................................Eremobates becki Muma 1986

Fondal notch triangular in form, distinctly longer than wide, and much wider than the base of the fixed cheliceral finger (Fig. 4); anterior tooth of the movable cheliceral finger distinctly tooth-like; metatarsus of palpus with or without scopula......................................................................................2

Metatarsus of palpus without scopula ..............................................Eremobates angustus Muma 1951

Metatarsus of palpus with a scopula of 30 to 40 papillae.........................Eremobates cruzi Muma 1951


Bibliography: