Eremocosta bajaensis Muma 1986

Eremocosta bajaensis (Muma 1986)

Eremorhax bajaensis Muma, 1986: 4–5, figs 8–12; Muma, 1987: 4–5, figs 8–12; Vázquez Rojas, 1995: 30; Vázquez Rojas, 1996: 76.

Eremopus bajaensis (Muma): Muma, 1989: 5 (key).

Eremocosta bajaensis (Muma): Harvey, 2002: 451; Harvey 2003: 245; Brookhart & Brookhart 2006: 303; Cushing, Channiago and Brookhart, 2018: 446-448, 450, 451, 453, 454, figs 1A, 2A-D, 3A, 4A, 5A.

Eremocosta spinipalpis (Kraepelin 1899): Cushing, Graham, Prendini, and Brookhart 2015: 285, 286, 288, 289, Table 2, figs. 1-3 (misidentiication).

 

ABOVE SPACE RESERVED FOR IMAGES FROM SCAN DATABASE

 

Diagnosis:

Chelicerae of male similar to that of Eremocosta calexicensis (Muma), but distinguished by the much smaller and more ridge-like (rather than tooth-like) medial tooth of the movable finger. Fondal notch short but distinct. Anterior edge of propeltidium dark. Wings of females' genital opercula thin and curved.


Holotype:

Male holotype from Baja California Norte, México, 2 miles east of Ranch San Salvador along road to Valle Trinidad from Ensenada; 21 June 1973; coll. S.C. Williams & K.B. Blair, SCW # 314(4) (CAS). Female allotype from 10.2 km north of Santa Maria, Baja California, México (CAS).


Original description:

Muma 1986: 4, 5, figs. 8-12:

4,5 - "Eremorhax bajaensis new species
Figures 8 to 12.

DIAGNOSIS: This species is distinguished from the closely related E. calexicensis Muma by the more extensively dusky propeltidia of both sexes, the slightly dusky palpal tarsi, the indistinct aborted anterior tooth of the male movable cheliceral finger and the smoothly curved widely separated posterior lobes of the female opercula.

MALES: Total length 32.0 to 34.0 mm. Holotype smaller measurements.

MALES: Total length, 17.0 to 23.0 mm.

 

Chelicera

Propeltidium

Palpus

Leg 1

Leg 4

LENGTH

8.4-9.4 mm.

4.4-4.4

31.0-32.5

23.0-25.0

38.0-40.0

WIDTH

3.6-3.9 mm.

6.0-6.8

CL/CW=2.34

PW/PL=1.45

A/CP=7.10

Coloration in alcohol pale to dusky-yellow with the palpi, legs, chelicerae, and venter unmarked. Eye tubercle dusky-purple with a black ring around eyes; propeltidium reticulate with dusky-purple except for a pale spot behind the eye tubercle; mesopeltidium, metapeltidium, and abdominal tergites reticulate with dusky-purple and somewhat darker on tergites; pleura of abdominal segments also dusky purple. Dentition of chelicerae as shown in figures 8 and 9. Fondal notch U-shaped, wider than deep, about half as wide as the base of the fixed finger and bearing one to three minute denticules. Mesal tooth large and distinct. Groove of fixed finger a flat, half-oval, mesoventral concavity that occupies about the distal half of the finger. Anterior tooth of movable finger a low flat ridge. Chelicerae longer than wide by a ratio of 1 to 2.3. Propeltidium wider than long by a ratio of 1 to 1.5. Other characters essentially as in E. calexicensis.

FEMALES: Total length 44.0 to 52.00 mm. Allotype smaller measurements.

 

Chelicera

Propeltidium

Palpus

Leg 1

Leg 4

LENGTH

6.1-7.3 mm.

2.9-3.2

30.0-34.0

24.0-27.0

39.0-44.0

WIDTH

3.6-3.9 mm.

4.4-5.6

CL/CW=2.31

PW/PL=1.61

A/CP=10.10

Coloration in alcohol similar to that of males except females are paler and propeltidial markings are not as distinct.

Dentition of chelicerae as shown in figure 10. Fondal notch as in males. Chelicerae longer than wide by a ratio of 1 to 2.3.

Opercula as in figures 11 and 12 of allotype and paratype.

General structure as in males but much more robust. Propeltidium wider than long by a ratio of 1 to 1.6. Mean appendage length 10.10 times the mean length of the combined chelicerae and propeltidium.

TYPE LOCALITY: Male holotype from 2 miles east of Rancho San Salvador along road to Valle Trinidad from Ensenada, Baja California Norte, Mexico on June 21, 1973 by S.C. Williams and K.B. Blair, deposited in California Academy of Science, San Francisco. Female allotype from 7 miles north Santa Maria, Baja California Norte, on July 12, 1969 by S.C. Williams and V. F. Lee, deposited in Callifornia Academy of Science, San Francisco. Female paratype with same data as allotype.

RECORDS: Male paratype from Campo, California on July 7, 1969 by Steve Parkis.

REMARKS: The legs of females of this species are distinctly proportionately longer thanthose of E. calexicensis and E. titania Muma. The above cited female paratype lacks the oval, anterior opercular concavities present on the female allotype."


Subsequent accounts:

Muma 1987: 4, 5, figs. 8-12:

4,5 - "Eremorhax bajaensis new species
Figures 8 to 12.

DIAGNOSIS: This species is distinguished from the closely related E. calexicensis Muma by the more extensively dusky propeltidia of both sexes, the slightly dusky palpal tarsi, the indistinct aborted anterior tooth of the male movable cheliceral finger and the smoothly curved widely separated posterior lobes of the female opercula.

MALES: Total length 32.0 to 34.0 mm. Holotype smaller measurements.

MALES: Total length, 17.0 to 23.0 mm.

 

Chelicera

Propeltidium

Palpus

Leg 1

Leg 4

LENGTH

8.4-9.4 mm.

4.4-4.4

31.0-32.5

23.0-25.0

38.0-40.0

WIDTH

3.6-3.9 mm.

6.0-6.8

CL/CW=2.34

PW/PL=1.45

A/CP=7.10

Coloration in alcohol pale to dusky-yellow with the palpi, legs, chelicerae, and venter unmarked. Eye tubercle dusky-purple with a black ring around eyes; propeltidium reticulate with dusky-purple except for a pale spot behind the eye tubercle; mesopeltidium, metapeltidium, and abdominal tergites reticulate with dusky-purple and somewhat darker on tergites; pleura of abdominal segments also dusky purple. Dentition of chelicerae as shown in figures 8 and 9. Fondal notch U-shaped, wider than deep, about half as wide as the base of the fixed finger and bearing one to three minute denticules. Mesal tooth large and distinct. Groove of fixed finger a flat, half-oval, mesoventral concavity that occupies about the distal half of the finger. Anterior tooth of movable finger a low flat ridge. Chelicerae longer than wide by a ratio of 1 to 2.3. Propeltidium wider than long by a ratio of 1 to 1.5. Other characters essentially as in E. calexicensis.

FEMALES: Total length 44.0 to 52.00 mm. Allotype smaller measurements.

 

Chelicera

Propeltidium

Palpus

Leg 1

Leg 4

LENGTH

6.1-7.3 mm.

2.9-3.2

30.0-34.0

24.0-27.0

39.0-44.0

WIDTH

3.6-3.9 mm.

4.4-5.6

CL/CW=2.31

PW/PL=1.61

A/CP=10.10

Coloration in alcohol similar to that of males except females are paler and propeltidial markings are not as distinct.

Dentition of chelicerae as shown in figure 10. Fondal notch as in males. Chelicerae longer than wide by a ratio of 1 to 2.3.

Opercula as in figures 11 and 12 of allotype and paratype.

General structure as in males but much more robust. Propeltidium wider than long by a ratio of 1 to 1.6. Mean appendage length 10.10 times the mean length of the combined chelicerae and propeltidium.

TYPE LOCALITY: Male holotype from 2 miles east of Rancho San Salvador along road to Valle Trinidad from Ensenada, Baja California Norte, Mexico on June 21, 1973 by S.C. Williams and K.B. Blair, deposited in California Academy of Science, San Francisco. Female allotype from 7 miles north Santa Maria, Baja California Norte, on July 12, 1969 by S.C. Williams and V. F. Lee, deposited in Callifornia Academy of Science, San Francisco. Female paratype with same data as allotype.

RECORDS: Male paratype from Campo, California on July 7, 1969 by Steve Parkis.

REMARKS: The legs of females of this species are distinctly proportionately longer thanthose of E. calexicensis and E. titania Muma. The above cited female paratype lacks the oval, anterior opercular concavities present on the female allotype."


Muma 1989: 5 (key) [as Eremopus bajaensis (Muma)]:

5 - "Key to species of striatus group (Males)

"1'. Movable cheliceral finger without a process distal of anterior teeth, a fixed finger that is
      gradually enlarged basally, and an elliptical mesoventral, ventral, or ectoventral groove not
      distinctly enlarged basally....................................................................................................4

4'.  Distinct groove of fixed cheliceral finger distal in position; minor teeth of movable cheliceral
      finger not on anterior margin of principal tooth..................................................................5

5.   Anterior tooth of movable chelicera! finger aborted to at most a tiny tooth-like spur; palpi
      and legs pale or indistinctly dusky..........................................................E. bajaensis (Muma)"

 

Harvey 2002: 451:

451 - Recognized Eremopus Roewer 1934 as a junior homonym of the copepod genus Eremopus Brady 1910, resurrected Eremocosta Roewer 1934, transferred Eremorhax bajaensis Muma 1986 to Eremocosta.

 

Harvey 2003e: 245:

245 - "Eremocosta bajaensis (Muma)

Eremorhax bajaensis Muma, 1986: 4–5, figs 8–12; Vázquez Rojas, 1995: 30; Vázquez Rojas, 1996: 76.

Eremopus bajaensis (Muma): Muma, 1989: 5.

Eremocosta bajaensis (Muma): Harvey, 2002: 451.

Type locality: 2 miles E. of Rancho San Salvador, Baja California, Mexico.

Distribution: Mexico, U.S.A. (California).".


Brookhart & Brookhart 2006: 303:

"303 - Eremocosta bajaensis Muma 1986

Eremorhax bajaensis Muma 1986:4.

Eremocosta bajaensis (Muma): Harvey 2002:451.

Type material.—Male holotype from 3.2 km east of Rancho San Salvador, Baja California, Mexico (CAS). Female allotype from 10.2 km north of Santa Maria, Baja California, Mexico (CAS).

Recorded specimens.—Two males and one female.

Distribution.—Mexico: Baja California Norte. Biome: Sonoran Desert.


Cushing, Graham, Prendini, and Brookhart 2015 (as Eremocosta spinipalpis (Kraepelin, 1899)): 282-285 (Table 2), 286 (Fig. 1), 288 (Fig. 2), 289 (Fig. 2):

282-285 - Table 2 provides the following locality data for the specimen utilized in the analysis: MEXICO: Baja Norte (no additional locale data). Specimen unique ID: UNAMspi.
The GenBank accession numbers for the specimen are identified as 16S: KT276624, CO1: KT276706, H3: KT276872, and 28S: KT276790

286, 288 - Figures 2 and 3 depict E. bajaensis (as E. spinipalpis) to be the sister taxon to (E. calexicensis + E. titania), with divergence estimated to be in the upper Miocene.


Cushing, Channiago and Brookhart, 2018: 446, 447 (text and Fig. 1A), 448 (Figs. 2A–D), 450, 451 (text and Fig. 3A), 453 (Fig. 4A), 454 (Fig. 5A)

446,447,450,451 - "Eremocosta bajaensis (Muma 1986)
Figs. 1A, 2A–D, 3A, 4A, 5A

Eremorhax bajaensis Muma 1986: 4–5, figs. 8–12.

Eremopus bajaensis (Muma 1987): Muma 1989: 5.

Eremocosta bajaensis (Muma 1986): Harvey 2002: 451.

Type material.—Male holotype from Arizona, USA, no further locality data (AMNH).

 Recorded specimens.—Known from type and 3 males.

 Distribution.—USA: Arizona. Mexico: Sonora.

 Biome: Sonoran Desert.

Type material. Male holotype from Baja California Norte, México, 2 miles east of Ranch San Salvador along road to Valle Trinidad from Ensenada; 21 June 1973; coll. S.C. Williams & K.B. Blair, SCW # 314(4) (CAS). Female allotype from 10.2 km north of Santa Maria, Baja California, México (CAS). Examined male holotype but was unable to examine female allotype.

Other specimens examined. Males (11). MÉXICO: Baja California Norte, 2 August 2002, coll. Rcho [sic] & Enriques (2 males: IBUNAM no number); USA: California, Riverside County, Santa Rosa Mountains, Highway 74, 1 mile W Pinyon Pines [fire station], N 33.58947°, W 116.47021°, 4000 m elev., 19 July 2005, coll. Wendell Icenogle, one male (collected near a female) on highway in car headlights at 01:30 hr (DMNS ZA.36272); USA: California, San Diego County, Alpine at home, N 32.83505°, W 116.76641°, 579 m elev., 3 July 2001, coll. D. Stokes (DMNS ZA.15433); USA: California, San Diego County, Rancho Jamul Ecological Reserve, N 32.683°, W 116.81836°, 249 m elev., 21 July 2005, coll. Dustin A. Woods, pitfall trap (DMNS ZA.16321); USA: California, San Diego County, Hollenbeck Canyon Wildlife Area, N 32.728°, W 116.815°, 524 m elev., July 2003, coll. USGS, pitfall trap (DMNS ZA.16323); USA: California, San Diego County, Rancho Jamul, N 32.683°, W 116.81836°, 249 m elev., July 2007, coll. USGS (RAJ), pitfall trap (DMNS ZA.19091); USA: California, San Diego County, San Diego Wild Animal Park [San Diego Zoo Safari Park], N 33.08983°, W 116.98668°, 201 m elev., 9–13 August 2010, coll. USGS, pitfall trap (DMNS ZA.33088); USA: California, San Diego County, San Diego Wild Animal Park [San Diego Zoo Safari Park], N 33.09153°, W 116.98241°, 20–24 July 2009, coll. USGS, pitfall trap (DMNS ZA.33089); USA: California, San Diego County, San Diego National Wildlife Refuge, N 32.72446°, W 116.94318°, 107 m elev., 3–7 August 2009, coll. USGS, pitfall trap (2 males: DMNS ZA.33091). Females (5). MÉXICO: Baja California Norte, 2 August 2002, coll. Rcho [sic] & Enriques (IBUNAM no number); USA: California, Riverside County, Santa Rosa Mountains, Highway 74, 1 mile W Pinyon Pines [fire station], N 33.58947°, W 116.47021°, 4000 m elev., 19 July 2005, coll. Wendell Icenogle, one female (collected near a male) on highway in car headlights at 01:30 hr (DMNS ZA.36272); USA: California, San Diego County, San Diego Wild Animal Park [San Diego Zoo Safari Park], N 33.09761°, W 116.98011°, 235 m elev., 12 September–16 January 2011, coll. USGS, pitfall trap (DMNS ZA.33051); USA: California, San Diego County, San Diego Wild Animal Park [San Diego Zoo Safari Park], N 33.09761°, W 116.98011°, 235 m elev., 17–21 August 2009, coll. USGS, pitfall trap (DMNS ZA. 33090); USA: California, San Diego County, Alpine area, N 32.8305°, W 116.76641°, 562 m elev., 15 September 2003, coll. unknown (DMNS ZA.36271)."

Diagnosis. Eremocosta bajaensis male chelicera is similar to that of E. calexicensis. It is distinguished by the much smaller and more ridge-like (rather than tooth-like) MM of the movable finger of E. bajaensis (compare Fig. 2A and E), a short but distinct fondal notch; color pattern of propeltidum (compare Fig. 5A and B), with E. bajaensis having a darker anterior edge; and color of appendages. Female genital operculum wings thin and curved (Fig. 4A) and very different from that of E. calexicensis (Fig. 4B).

Measurements. Male holotype. TL 21.0; CL 5.5; CH 2.3; FNL 0.3; FNH 0.6; FFH 0.9; PL 19.2; PT 1.8; PMT 7.0; LI 16.0; LIV 25.0; PPL 4.2; A/CP 6.2; FNL/FNH 0.5; FFH/FNH 1.5.

Males (n = 11). TL 27.0–34.0; CL 7.5–9.1; CH 3.4–4.5. FNL 0.3–1.0; FNH 0.4–1.0; FFH 0.8–1.0; PL 21.0– 34.0; PT 1.9–4.0; PMT 4.0–7.9; LI 14.5–23.0; LIV 26.0–37.0; PPL 3.4–5.0; A/CP 5.1–7.3; FNL/FNH 0.5–1.0; FFH/FNH 0.8–2.1; FFH/CH 0.2–0.3.

Females (n = 5). TL 30.0–40.0; CL 8.9–12.1; CH 5.0–5.0; PL 21.0–30.0; PT 1.4–2.1; PMT 6.4–6.9; LI 18.0– 21.5; LIV 30.0–35.0; PPL 4.9–6.4; A/CP 4.4–5.5.

Description. Male holotype. Coloration. Overall dusky yellow, appendages the same; propeltidium lightly reticulate brownish-violet with dark anterior edge (Fig. 5A). Pale oval behind eye tubercle (Fig. 5A). No distinct abdominal coloration. Malleoli white.

Chelicera. Male. VDC deep, occupying approximately half the length of fixed finger (Fig. 1A), narrower than E. calexicensis (Fig. 1B). Thin, straight fixed finger with no median dentition; movable finger: MP-MSM-MM (a tiny medial tooth or ridge); MPL distinct (Figs. 2A & B). Fondal notch short; three RFA; fondal teeth graded II, I, III, IV retrolaterally and I, III, II, IV prolaterally (Fig. 3A).

Setation. Male. Typical male setation. Palp with long, thin setae scattered throughout. A pair of long thin setae just proximal to the tibia-femur joint. A few scattered bacilli on the coxa of LII, LIII, and LIV.

Coloration. Female. As in males but slightly lighter.

Chelicera. Female. Fixed finger: FP-2 FSM (posterior being larger)-FM-smaller FSD-FD; Movable finger: MP-2 MSM-MM; MPL distinct (Fig. 2C & D). Two RFA proximal to FP; fondal teeth graded II, I, III, tiny IV retrolaterally and I, III, II, IV prolaterally.

Setation. Female. Typical.

Genital Operculum. All of the females examined match Muma’s illustration (1987, p. 25, fig. 12) with long, curved anterior arms widening at the posterior wing (Fig. 4A). None had the pits on the anterior arms as illustrated in Muma’s fig. 11.

Distribution. Eremocosta bajaensis appears to occupy an area extending from coastal southern California west of the Peninsular Ridge into Baja de Norte, México. This is the species identified as E. spinipalpis by Cushing et al. (2015). A male and female were also collected as far inland as the Santa Rosa Mountains in Riverside County, California. Collections by USGS, San Diego found E. bajaensis from April to September numbering 6 males and 4 females. Muma’s (1951) list of E. calexicensis from coastal California, San Diego Co. may have been this species.


Distribution:

MEXICO: Baja California; UNITED STATES: Arizona, California.

 

ABOVE SPACE RESERVED FOR MAP FROM SCAN DATABASE

 

Notes:

Partial sequences of the histone H3 (H3) gene [Accession KT276872.1], the 16S ribosomal RNA gene [Accession KT276624.1], the 28s ribosomal RNA gene [Accession KT276790.1], and the cytochrome c oxidase subunit 1 (COI) gene [Accession: KT276706.1] are available in GenBank under Eremocosta spinipalpis (Kraepelin, 1899) (misidentified as such in Cushing, Graham, Prendini and Brookhart (2015); identification corrected in Cushing, Channiago and Brookhart (2018).


Bibliography: