Gryllus fultoni (Alexander)

Weissman, David B. & Gray, David A., 2019, Crickets of the genus Gryllus in the United States (Orthoptera: Gryllidae: Gryllinae), Zootaxa 4705 (1), pp. 1-277 : 126-129

Gryllus fultoni (Alexander)

Southern Wood Cricket

Figs 57 , 113–115 , 122–126, Table 1

1957 Acheta fultoni . Alexander (1957). Holotype male ( Fig. 123 , courtesy of M. O’Brien): Ohio, Hocking Co., Goodhope Township . Deposited at UMMZ. Types also photographed on OSF.

1964. Gryllus fultoni . Randell (1964).

‘ Gryllus #28’ of DBW notebooks.

Distribution. East of 98° longitude in southern and central US, to the Atlantic coast and south into Florida.

Recognition characters and song. Small to medium sized cricket, always short hind wings, usually with contrasting yellow cerci when alive, head usually narrower that pronotum ( Fig. 124 ). Song ( Fig. 125 ) of 3p/c delivered at 250 to 360 c/m., PR 35–55. Usually lives in woods or on their edges but sometimes in short to long roadside grasses. Some males climb several feet into bushes and tree trunks to sing. One “effective” generation/year (see below under Life cycle). Differs from sympatric G. vernalis in not being a forest obligate, being slightly larger ( Fig. 120 ), tegmina brown and black with tegminal bar vs. solid black in G. vernalis , no overlap in teeth/mm ( Table 1 , p. 18), PR faster (can hear difference in field when both species singing at same temperature), and yellow cerci common in live individuals (rare in G. vernalis ). Differs from sympatric G. veletis in microhabitat (woods vs. grassland), G. fultoni frequently having the head narrower than pronotum, longer cerci that are usually yellow, smaller size, fewer p/c, and faster PR and CR. Differs from sympatric G. veintinueve in G. fultoni usually having yellow cerci when alive, head narrower than pronotum, faster CR and fewer file teeth, no overlap in its faster PR and different DNA ( Fig. 6 , p. 28 ; Gray et al. 2019).

Derivation of name. Named, by Alexander, in honor of B. B. Fulton who was the first to recognize this species as distinct.

Geographic range. ( Fig. 126 ). From eastern Texas, Oklahoma, and Kansas through the central US to the Atlantic coast and south into Florida (see maps in Walker 2019; Jang & Gerhardt 2006a, b).

Habitat. Usually in woods or along their borders where they live in leaf litter and can be difficult to collect. Never in open fields. Also in holes in the ground under trees where they are easily flushed with water. Occasionally in short roadside grasses (Kansas, S87-69 & 70) with an open tree cover. In eastern Oklahoma males climb into bushes and trees to sing—we collected males singing 1.5–2m above ground on the side of a tree at Keystone State Park (S88-42) and in Tulsa (S07-22).

Life cycle and seasonal occurrence. No egg diapause (checked from Kansas, S87-70; Oklahoma, S88-42; and Missouri, S00-16), with first field adults in mid-late May. Walker (1974) notes that northern Florida can have second generation G. fultoni adults, similar to the situation seen in G. veletisoides in California (see p. 195), G. veletis in Mich- igan ( Alexander 1957, p. 592), and G. firmus in Florida ( Walker 1980). The functionality of this second generation in Florida is unknown but apparently non-contributory to the gene pool (T.J. Walker pers. comm. to DBW, 2011).

Variation. Color: See Fig. 124 above. Head width: 28 of 36 males with head narrower than pronotum while 29 of 31 females with head narrower than pronotum. Size: Florida specimens are larger than more northern ones.

Specimens examined. Arkansas: Garland Co., Lake Ouachita State Park , 16-vi-1995 , T.J. Walker. Indiana: Crawford Co., Hwy 62 11.6 m W intersection with Hwy 135, 750’, 4-vi-2003 (S03-62) . Kansas: Barber Co., 1 m W Medicine Lodge on Hwy 160, 23-vi-1987 (S87-69) . 27 m W Medicine Lodge on Hwy 160, 1750’ 23-vi-1987 (S87-70) . Missouri: Hickory Co., Pomme de Terre State Park , 1000’, 20-vii-1993 (S93-49) . Jefferson Co., Edmond A. Babler State Park , 750’ 2-vi-2003 (S03-56) . Stone Co., Table Rock Dam Visitor Center , 31-v-2000 (S00-16) T.J. Walker. Ohio: Hocking Co. (near type locality), Hwy 33 9 m S Lanchester , 750’, 5-vi-2003 (S03-64) . Oklahoma: Ataka Co., Jack Fork Mts. 3 m SW Daisy on Hwy 43, 750’, 1-v-1988 (S88-46) . Osage Co., near Walnut Creek State Park , 600’ 15-vi-1988 (S88-43) . Tulsa Co., Keystone State Park , 600’, 15-vi-1988 (S88-42) ; Lake Keystone Dam Area 650’, 27-v-2001 (S01-47) ; Tulsa , at intersection I44 and Hwy 244, 680’, 9-vi-2007 (S07-22) ; near Tulsa, Exit 238 off I44 2 m E Tulsa city limit, 796’, 15-vii-2013 (S13-68), 36° 09’ 37.4 -95° 47’ 33.1”. Texas: Bastrop Co., Bastrop State Park , 700’ 31-v-1991 (S91-23) . Marion Co., Caddo Lake State Park , 300’, 18-vi-1993 (S93-42).

DNA. Multilocus G34 (Indiana, S03-62) sister species with G. vernalis and G. cayensis (Gray et al. 2019) . ITS2 shows clear and complete separation between G. fultoni and G. vernalis ( Fig. 115 , p. 121), whereas two G. fultoni ( Fig. 122 , p. 125 ) from Missouri (G38 and G1703, both S03-56) have 16S sequences identical to microsympatric G. vernalis , suggesting the possibility of past hybridization.

Discussion. G. fultoni occurs microsympatric in Missouri (S03-56), Indiana (S03-62), and Ohio (S03-64) with G. vernalis ; in Oklahoma (S88-42, S01-47 and S13-68) with G. veintinueve ; and in Oklahoma (S13-68) with G. veletis . Thus, at the latter Oklahoma locality just east of Tulsa (S13-68), there are 3 Gryllus taxa synchronic and microsympatric that can have 3p/c with different PR and CR. Apparently females can discriminate between such small differences in songs.

Although called the southern wood cricket, the distribution of G. fultoni extends north of the northern wood cricket, G. vernalis (see Fig. 126 and Jang & Gerhardt 2006a, b).

Those males singing in woodlands and grassy areas can be difficult to catch because they sing from under dry leaves and other vegetation. Those males singing in bushes and on tree trucks may jump on approach and get lost in the forest duff. A large butterfly net positioned beneath the male can help in these situations. Aggressiveness in this taxon studied by Jang et al. (2008).

Figures

FIGURE 6. Phylogenetic arrangement of taxa redrawn from Gray et al. (2019). Taxa in grey text are either not considered here because they are not US Gryllus, or are considered only briefly (Pet Store Group; G. bryanti).

FIGURE 28. Five second waveforms of calling songs of (A) G. pennsylvanicus and (B) G. firmus. G. pennsylvanicus (R04-110) Whatcom Co., WA (S04-91), at 25°C. G. firmus: (R03-255) Gainesville, FL (S03-85), at 25°C.

FIGURE 57. ITS2 gene tree. G. veintinueve samples: S02-39 (G134); S07-21 (G1139); S07-27 (G1140, G1211); S09-71 (G1451); OK, Love Co., Hwy 32 at Boggy Creek (2015-055). G. vernalis samples: S03-56 (G27, G1739); S03-62 (G31, G33). G. fultoni samples: S03-62 (G32, G34); S03-64 (G35), S07-22 (G1138). G. veletis samples: S03-58 (G39); S03-60 (G30); S15-9 (G2939); S15-16 (G2927, G2934); S15-21 (G2899); S15-24 (G2936); S15-25 (G2963, G2968, G2983); S15-53 (G3304, G3343).

FIGURE 113. Five second waveforms of calling songs of (A) G. fultoni and (B) G. vernalis. G. fultoni: (R03-86) Hocking Co., OH (S03-64), at 25°C; G. vernalis: (R03-104) Jefferson Co., MO (S03-56), at 24.5°C.

FIGURE 114. One second spectrograms of (A) G. fultoni and (B) G. vernalis, same males as in Fig. 113.

FIGURE 115. ITS2 gene tree. G. vernalis samples: S03-56 (G27, G1739); S03-62 (G31, G33). G. fultoni samples: S03-62 (G32, G34); S03-64 (G35), S07-22 (G1138).

FIGURE 120. Size and color comparison of G. vernalis (left, S03-56, Jefferson Co., MO) vs. G. fultoni (right, S03-62, Crawford Co., IN).

FIGURE 122. 16S gene tree and distribution map showing two 16S Clades for both G. vernalis and G. fultoni (the latter situation is discussed, below, under G. fultoni). G. vernalis samples: S03-56 (G26, G27, G1740); S03-57 (G28, G1700, G1701, G1738); S03-62 (G31, G33, G440); S14-35 (G2754, G2755). G. fultoni samples: S01-47 (G1704); S03-56 (G38, G1703); S03- 62 (G32, G34); S03-64 (G35, G1712); S07-22 (G1020, G1138).

FIGURE 123. Holotype male (upper) G. fultoni and allotype female (bottom), with labels.

FIGURE 124. Color variation in G. fultoni: female (left) and both males (middle and right), all three from Crawford Co., IN (S03-62). Note narrow heads, especially in male on right, and separation of female tegmina.

FIGURE 125. Calling song (R03-86) of G. fultoni from Hocking Co., Ohio (S03-64), recorded at 25°C.

FIGURE 126. Populations of G. fultoni that we studied. See Walker (2019) for more eastern localities.