Short-legged daddy-long-leg spiders in North America: the genera Pholcophora and Tolteca (Araneae, Pholcidae)
Author
Huber, Bernhard A.
33607F65-19BF-4DC9-94FD-4BB88CED455F
Zoological Research Museum Alexander Koenig, LIB, Bonn, Germany. Laboratory of Arachnology (LATLAX), Institute of Biology, Universidad Nacional Autónoma de México-Tlaxcala, San Miguel Contla, Santa Cruz Tlaxcala, Tlaxcala, México. Department of Genetics and Microbiology, Faculty of Science, Charles University, Prague, Czech Republic. Campus Amílcar Ferreira Sobral, Universidade Federal do Piauí, Floriano, Piauí, Brazil.
b.huber@leibniz-lib.de
Author
Meng, Guanliang
7E8C41F8-77BB-468F-BE9A-D3F1DFCA1E4E
Zoological Research Museum Alexander Koenig, LIB, Bonn, Germany. Laboratory of Arachnology (LATLAX), Institute of Biology, Universidad Nacional Autónoma de México-Tlaxcala, San Miguel Contla, Santa Cruz Tlaxcala, Tlaxcala, México. Department of Genetics and Microbiology, Faculty of Science, Charles University, Prague, Czech Republic. Campus Amílcar Ferreira Sobral, Universidade Federal do Piauí, Floriano, Piauí, Brazil.
G.Meng@leibniz-lib.de
Author
Valdez-Mondragón, Alejandro
F043A1C7-2B83-40C9-A74E-82C92F00725A
lat_mactans@yahoo.com.mx
Author
Král, Jiří
E836F3B5-D704-4EEC-966A-0C4F1FAD324B
spider@natur.cuni.cz
Author
Ávila Herrera, Ivalú M.
E3687584-7F64-450D-9492-BE0DD4864AD6
ivalu.a@gmail.com
Author
Carvalho, Leonardo S.
28AA7D67-3C9D-495E-8C17-33D35F1A0FAC
carvalho@ufpi.edu.br
text
European Journal of Taxonomy
2023
2023-07-17
880
1
1
89
http://zoobank.org/3f806fd6-2eb3-456a-afd7-780a0fbeb2da
journal article
55344
10.5852/ejt.2023.880.2173
339bce42-a7e7-418b-b9ac-4588e4219b15
2118-9773
8155472
3F806FD6-2EB3-456A-AFD7-780A0FBEB2DA
Genus
Pholcophora
Banks, 1896
Pholcophora
Banks, 1896: 57
.
Type
species:
P. americana
Banks, 1896
.
Pholcophora
–
Gertsch 1971: 76
;
1977: 112
;
1982: 96
. —
Huber 2000: 113
.
Diagnosis
Easily distinguished from only other North American
Ninetinae
genus
Tolteca
by strong male cheliceral apophyses originating proximally (
Figs 5A–B
,
10A–B
; in
Tolteca
small and originating distally); also by presence of stridulatory ridges on male chelicerae; most species (except
P. tehuacan
Huber
sp. nov.
) also by larger size (body length ~1.7–3.1; in
Tolteca
~1.1–1.4) and longer legs (tibia 1>1.0, in
Tolteca
<0.7); from most species of
Tolteca
also by absence of knob-shaped structure between epigynum and pedicel (also absent in
Tolteca sinnombre
Huber
sp. nov.
). From other geographically close genera (
Papiamenta
,
Galapa
) also by simple rod-shaped procursus (
Figs 5C–E
,
10C–E
; much shorter in
Papiamenta
; with dorsal process in
Galapa
); by presence of humps on male sternum (absent in
Papiamenta
); and by unmodified male cheliceral fangs (with processes in
Galapa
).
Description
Male
MEASUREMENTS
. Total body length 1.2–3.1, carapace width 0.55–1.40. Legs relatively short, tibia 1: 0.65–1.85, i.e., 1.2–2.0 × carapace width; tibia 1 L/d 8–16; tibia 2 much shorter than tibia 4 (tibia 2 / tibia 4: 0.75–0.85).
COLOUR
. Live specimens (
Fig. 3
) ochre to brown, prosoma sometimes reddish (which is lost in ethanol); carapace monochromous, sometimes with indistinct darker median Y-mark; abdomen colour slightly variable, usually monochromous, sometimes with indistinct dorsal marks (bluish in ethanol); legs without dark or light bands, femora sometimes distally darkened.
BODY
. Ocular area barely raised (cf.
Fig. 8A
), eight eyes, AME relatively large, diameter 20–60 µm, 45–75% of PME diameter; carapace with low and indistinct thoracic groove (cf.
Figs 8A
,
13A
). Clypeus unmodified but sometimes slightly more protruding than in female. Sternum wider than long, with pair of distinct anterior processes near leg coxae 1. Abdomen globular; gonopore with four epiandrous spigots arranged in two pairs (
Fig. 29C
; examined:
P. americana
Banks, 1896
;
P. tehuacan
sp. nov.
); ALS with seven spigots each (cf.
Figs 8C
,
29G
): one strongly widened spigot, one long pointed spigot, and five cylindrical spigots (one of which is unusually large); PMS with two short, pointed spigots; PLS without spigots.
CHELICERAE
. With one pair of large frontal apophyses (
Figs 5A–B
,
10A–B
); with stridulatory files (
Fig. 29A
), distances between ridges ~2.0–3.8 µm, distances proximally often smaller than distally.
PALPS
. Coxa unmodified; trochanter barely modified (with indistinct or without ventral projection); femur proximally with retrolateral-ventral process and prolateral stridulatory pick (modified hair), distally widened but simple, slightly curved towards dorsal, in
P. texana
Gertsch, 1935
with distinctive brush of feathered hairs ventrally (
Fig. 19A, C
); femur-patella joints slightly shifted toward prolateral side; tibia globular, with two trichobothria; tibia-tarsus joints not shifted to one side; palpal tarsal organ raised, capsulate with small opening (
Fig. 29E
; diameter of opening ~1.5 µm – measured in
P. tehuacan
sp. nov.
only); procursus simple and straight, without dorsal flap, not strongly elongated, often with semi-transparent distal element; genital bulb distally cone-shaped, with species-specific sclerotized and membranous elements.
LEGS
. Without spines and curved hairs; in some species with very short vertical hairs in higher than usual density on tibiae (only anterior tibiae or all tibiae) (length of hairs ~30 µm). Trichobothria in usual arrangement: three on each tibia (except tibia 1: prolateral trichobothrium absent), one on each metatarsus; slightly feathered (
Figs 18F
,
24E
); length of dorsal trichobothrium on tibia 1: ~90 µm; retrolateral trichobothrium of tibia
1 in
very distal position (at 50–65% of tibia length). Tarsus 1 with 5–8 pseudosegments, sometimes only distally fairly distinct; tarsus 4 distally with one comb-hair on prolateral side (cf.
Figs 13H
,
24H
); leg tarsal organs very small, capsulate with small opening (cf.
Fig. 8F–H
; diameter of opening ~1.3–1.8 µm); three claws (cf.
Figs 13G
,
24G
,
29H
).
Female
In general (size, colour) similar to male but sternum without pair of anterior humps, leg tibia 1 with usual low number of short vertical hairs, and chelicerae without stridulatory ridges; legs either slightly shorter than in males or of same length (only
P. americana
with reasonable sample size: male/female tibia 1 length: 1.12). Spinnerets, comb-hairs, and leg tarsal organs as in male; palpal tarsal organ slightly less strongly raised (
Figs 18E
,
23H
). Epigynum main (anterior) plate large, rectangular to oval, sometimes posteriorly excavated, weakly protruding in lateral view; posterior plate also large, short but wide, median part sometimes separated from lateral parts by whitish band. Without knob-shaped structure between epigynum and pedicel. Internal genitalia variable: either without sacs (
Fig. 33A–H;
P
. americana
Banks, 1896
;
P. mazatlan
Huber
sp. nov.
;
P. papanoa
Huber
sp. nov.
;
P.
“Mex354”) or with pair of distinct membranous sacs (
Fig. 33I–L;
P
. texana Gertsch, 1935;
P. tehuacan
sp. nov.
); in Caribbean ‘
Pholcophora
’ with single median tube-like sac (
Fig. 33M–N;
P
. bahama
Gertsch, 1982
;
P.
“
Car
544”;
P.
“Cu12-325”); with pair of distinct transversal sclerites; apparently without pore plates (possibly with very indistinct pair of pore plates near median line, indicated in
Fig. 33E–F, J–L
).
Relationships
In the molecular analysis of
Eberle
et al.
(2018)
, the
type
species
Pholcophora americana
was part of a North American-Caribbean clade of
Ninetinae
, together with “
Pholcophora
?
Car
544”, an unidentified Cuban species (“Gen. Cu12-325”; treated below as “
Pholcophora
? Cu12-325”), and the genus
Papiamenta
. The genus
Tolteca
was not included.
Our new molecular analyses mostly support this North American-Caribbean clade (
Fig. 1
; see also general results of molecular analyses above), and they also support the idea that Caribbean ‘
Pholcophora
’ are not true
Pholcophora
but more closely related with the Caribbean genus
Papiamenta
. Our analyses suggest a sister group relationship between true
Pholcophora
and the Caribbean clade (
Papiamenta
+ Caribbean ‘
Pholcophora
’). By contrast, preliminary analyses of UCE data (G. Meng, L. Podsiadlowski, B.A. Huber, unpubl. data) suggest a sister-group relationship between true
Pholcophora
and
Tolteca
. Since we consider these UCE results more reliable, we will not further discuss relationships here, except for two species not yet included in any molecular dataset:
Pholcophora maria
Gertsch, 1977
from Yucatán, and
Pholcophora bahama
Gertsch, 1982
from
the Bahamas
. Judging from the female internal genitalia (compare
Huber 2000
: fig. 1357 with
Fig. 28B
), we hypothesize that
Pholcophora maria
is closely related with the newly described
P. tehuacan
sp. nov.
It is thus probably a true
Pholcophora
.
Pholcophora bahama
resembles “
Pholcophora
?
Car
544” in having a median tube-like sac in the female internal genitalia (compare
Huber 2000
: fig. 1356 with
Fig. 31G
). It is thus probably not a true
Pholcophora
but part of the Caribbean clade.
Distribution
The genus appears limited to North America (
Fig. 2
); Caribbean species (including Dominican amber fossils) currently placed in
Pholcophora
are probably misplaced (see Relationships above). Of the seven North American named species, six are largely or entirely restricted to
Mexico
.
Natural history
Gertsch (1982)
briefly characterized
Pholcophora
spiders as living “reclusive lives under ground objects, in leaf and plant detritus, and in soil openings and caves”, and mentioned that they “spin web tangles in dark spaces and remain there in close contact with such webs as permanent residents, often in informal colonies”. Our newly collected species and specimens fit this description. Most were collected by turning rocks or sifting litter in shady spots of low and dry forests (
Fig. 34
). They usually shared the microhabitat with one or more other pholcids. In only one case we found two species of
Pholcophora
at a single locality; we never found
Pholcophora
to share a locality with
Tolteca
. Females carried their flattened egg-sacs slightly under the prosoma (
Fig. 3
); eggs sacs contained ~6–
30 eggs
, each with a diameter of ~
0.40–0.60 mm
(
Huber & Eberle 2021
). Some females had a genital plug (cf.
Fig. 16C
).
Composition
The genus now includes 11 nominal species. Of these, seven occur in North America and are here considered to represent ‘true’
Pholcophora
:
Pholcophora americana
Banks, 1896
;
P. maria
Gertsch, 1977
;
P. mazatlan
sp. nov.
;
P. mexcala
Gertsch, 1982
;
P. papanoa
sp. nov.
;
P. tehuacan
sp. nov.
;
P. texana
Gertsch, 1935
. The Caribbean
P. bahama
Gertsch, 1982
is here considered to be misplaced (see Relationships above). All extant species are treated below except
P. bahama
and
P. mexcala
for which we have no new data [in 2019 we searched at four localities close to Mezcala (= “Mexcala”) but could not find
P. mexcala
].
Fig. 2.
Known distributions of ‘true’
Pholcophora
Banks, 1896
(orange marks) and of presumably misplaced Caribbean ‘
Pholcophora
’ and of
Papiamenta
Huber, 2000
(red marks). Dominican amber species currently placed in
Pholcophora
are represented by an “F” in a pink square. Our molecular data suggest that Caribbean ‘
Pholcophora
’ are more closely related with the genus
Papiamenta
than with true
Pholcophora
. Barcoded specimens of
Pholcophora americana
Banks, 1896
are marked with an “x” and accompanied by the vial code (see Table 1 for details).
Three nominal species are only known from amber fossils originating from Hispaniola (
Wunderlich 1988
):
P. brevipes
Wunderlich, 1988
;
P. gracilis
Wunderlich, 1988
; and
P. longicornis
Wunderlich, 1988
. We did not re-examine the amber specimens but judging from their geographic origin we speculate that the three species are part of the clade including Caribbean ‘
Pholcophora
’ and
Papiamenta
. However, the three amber species fit the diagnosis above with respect to the strong male cheliceral apophyses originating proximally and the simple rod-shaped procursus. They are unusually small (but in this respect similar to the exceptionally small extant
P. tehuacan
sp. nov.
and
P. maria
), and the original descriptions remain silent about male cheliceral stridulation and male sternal humps. The females of the three fossil species remain unknown.