Nylanderia steinheili (Forel, 1893)

Figs. 89–91 (worker); 92–96 (male)

Prenolepis steinheili Forel, 1893: 342 (worker). Lectotype worker, ST. THOMAS, Antilles, 13.X.78 (examined) (MHNG). Forel, 1908: 64 (queen); Forel, 1912: 66 (male). Lectotype designated by Trager, 1984. Combination in Nylanderia (Nylanderia): Forel, 1912: 66; in Paratrechina (Nylanderia): Emery, 1925 d: 223; in Nylanderia: Kempf, 1972: 168; in Paratrechina: Brandão, 1991: 367; in Nylanderia: LaPolla, Brady & Shattuck, 2010: 127 .

Prenolepis steinheili var. minuta Forel, 1893: 343 (worker, queen and male). 6 syntype workers, 3 syntype queens and 3 syntype males, ST. VINCENT, Antilles (examined; lectotype worker here designated (USNMENT00754828); specimen on pin with three separate points; point with lectotype marked with small red dot) (MHNG). Combination in Nylanderia (Nylanderia): Forel, 1912: 66; in Paratrechina (Nylanderia): Emery, 1925: 223; in Nylanderia: Kempf, 1972: 168; in Paratrechina: Brandão, 1991: 367; in Nylanderia: LaPolla, Brady & Shattuck, 2010: 127 . SYN. NOV.

Worker diagnosis: Dark brown, contrasting sharply with white trochanters and meso/metacoxae; mesosomal dorsum and gastral tergite 1 with moderate to dense pubescence.

Compare with: N. guatemalensis

WORKER. Measurements (n=12): TL:1.70–2.30; HW: 0.49–0.57; HL: 0.57–0.67; EL: 0.14–0.19; SL: 0.63– 0.84; WL: 0.71–0.88; GL: 0.69–0.96. SMC: 12–23; PMC: 2–4; MMC: 2–3. Indices: CI: 81–91; REL: 22–30; SI: 118–155; SI2: 17–24.

Head: sides of head in full face view nearly parallel to rounded; posterolateral corners rounded; posterior margin straight, sometimes slightly emarginate medially; anterior clypeal margin nearly straight to slightly emarginate; median ocellus sometimes present; eyes well-developed. Mesosoma: in lateral view, pronotum convex; anterior margin of mesonotum raised slightly above posterior pronotal margin; metanotal area without short flat area before spiracle; dorsal face of propodeum slightly convex; dorsal face of propodeum and mesonotum approximately the same height or propodeum slightly lower than mesonotum in lateral view. Color and pilosity: body dark brown, trochanters, mesocoxa and metacoxae white; antennae and mandible lighter brown than head, mesosoma and gaster; pubescence abundant across body except mesopleuron and lateral portions of pronotum which are without pubescence.

QUEEN. Measurements (n=3): TL: 3.20–3.40; HW: 0.73–0.78; HL: 0.73–0.78; EL: 0.23–0.24; SL: 0.79–0.89; WL: 1.20–1.30; GL: 1.50–1.80. SMC: 10–12; PMC: 3–6; MMC: 11–12. Indices: CI: 99–105; REL: 31–33; SI: 107–119.

Generally, as in worker with modifications expected for caste.

MALE. Measurements (n=3): TL: 1.70–1.96; HW: 0.52–0.53; HL: 0.50–0.52; EL: 0.19–0.20; SL: 0.62–0.71; WL: 0.75–0.80; GL: 0.70–0.80. SMC: 8–14; PMC: 0; MMC: 10–16. Indices: CI: 99–106; REL: 37–39; SI: 119– 133.

Head: sides of head in full face view rounded; posterior margin rounded; clypeus nearly straight anteriorly; mandible with distinct apical tooth and much smaller, often indistinct, subapical tooth adjacent to apical tooth; basal angle indistinct. Mesosoma: in lateral view, dorsal margin of mesoscutum same as height as dorsal margin of mesoscutellum; propodeum steeply sloping without distinct dorsal and declivitous faces. Genitalia: gonopod apex coming to triangular point in lateral view; gonopod margin in dorsal view curves away from penial sclerite; digitus with pointed apex that bends away from penial sclerite; cuspis tubular, rounded at apex bending sharply toward digitus; anteroventral process of penial sclerite coming to point with ventral margin of process emarginate; valvura of penial sclerite placed ventral to midline (fig. 105). Color and pilosity: body typically dark brown with contrasting yellow-white to yellowish-brown (typically not as light as in workers) trochanters, and mesocoxa and metacoxa; antenna and mandible lighter brown than head, mesosoma and gaster; pubescence abundant across body except on mesopleuron which is without pubescence.

Other material examined: ANGUILLA: Shoal Bay Rd, quarry turnoff, 18.249° N, 63.033° W, 21/May/2006, #106, JK Wetterer; Windward Point sea grapes on hill, 18.280° N, 62.968° W, 20/May/2006, #86, JK Wetter- er; The Quarter, N Tanglewood Rd, 18.217° N, 63.040° W, 20/May/2006, #71, JK Wetterer; Long Bay, scrub, 18.197° N, 63.126° W, 18/May/2006, #46, JK Wetterer ; near Abadam Hole, under tree, 18.273° N, 62.975° W, 20/May/2006, #81, JK Wetterer; Lake’s Quarry, 18.248° N, 63.037° W, 21/May/2006, #105, JK Wetterer; Meads Bay hotel grounds, 18.183° N, 63.143° W, 17/May/2006, #13, JK Wetterer ; Maunday’s Bay, sea grapes, 18.171° N, 63.144° W, 21/May/2006, #100, JK Wetterer ; Airport, parking, 17.139° N, 61.794° W, 13/Jul/2007, #519, JK Wetterer; Wellings, 10 min up trail, 17.032° N, 61.825° W, 26/May/2007, #374, JK Wetterer; ARUBA: Bubali by sanctuary tower, 12.562° N, 70.048° W, 2/Aug/2007, #735, JK Wetterer ; BARBADOS: Trents clump of viny tree, 13.298° N, 59.633° W, 20/Jun/2006, #410, JK Wetterer; Canefield forest patch, 13.193° N, 59.590° W, 16/Jun/2006, #346, JK Wetterer; Lakes Beach, beach, 13.245° N, 59.556° W, 20/Jun/2006, #442, JK Wetterer; Boarded Hall forest, 13.209° N, 59.576° W, 16/Jun/2006, #349, JK Wetterer ; Turner’s Hall Woods, 26/Nov/2003, #100, Wetterer; Codrington College campus, 13.172° N, 59.479° W, 21/Jun/2006, #446, JK Wetterer; Breedy’s scrub forest, 13.251° N, 59.590° W, 16/Jun/2006, #354, JK Wetterer; Bath near route H3, 13.182° N, 59.482° W, 21/Jun/2006, #440, JK Wetterer; Hackleton Cliff base forest, 13.203° N, 59.536° W, 16/Jun/2006, #357, JK Wetterer; BARBUDA: Sand Ground, plantation, 17.602° N, 61.830° W, 8/Jul/2007, #431, JK Wetterer ; BRITISH VIRGIN ISLANDS: Tortola, Sabbath Hill, by sewer tank, 18.435° N, 64.598° W, 16/Nov/2005, #379, JK Wetterer ; Sage Mtn Rd, parking by park, 18.412° N, 64.656° W, 15/Nov/2005, #356, JK Wetterer; Chalwell Hill, by radio tower, 18.425° N, 64.645° W, 16/Nov/2005, #374, JK Wetterer; Martins Joes Hill, Joes Hill Rd, 18.427° N, 64.638° W, 18/Nov/2005, #397, JK Wetterer; DOMINICA: Concord, Hotel garden, 10/Jun/2004, #167, JK Wetterer; Central For. Res., 7 km SW Concord, 11/Jun/2004, #169, JK Wetterer; La Source, 11/Jun/2004, #186, JK Wetterer; La Plaine, 14/Jun/2004, #208, JK Wetterer ; DOMINICAN REPUBLIC: Santo Domingo, Botanical Garden, 9/Dec/2003, Mark Deyrup; Parque Nacional Sierra de Baharuco, 18° 09.310’ N, 71° 45.495; W, elev. 277 m; under leaf litter, 27 vii.2009; SA Schieder & JS LaPolla ; GRENADA: Grand Etang, Morne La Bay, 9/Nov/2003, #12, JK Wetterer; woodlands, cane by factory, 12.025° N, 61.741° W, 28/Jun/2006, #552, JK Wetterer; Coral Cove, 11/Nov/2003, #32, JK Wetterer; Trant’s Bay, W of road by end, 16.753° N, 62.164° W, 19/Jul/2007, #654, JK Wetterer; Old Road Bay, waterfront, 16.742° N, 62.232° W, 16/Jul/2007, #589, JK Wetterer ; MONTSERRAT: Cavala Hill by church, 16.779° N, 62.204° W, 20/Jul/2007, #661, JK Wetterer; Mars Hill Oriole trailhead, 16.770° N, 62.207° W, 16/Jul/2007, #594, JK Wet- terer ; NEVIS: Tower Hill forest, 17.162° N, 62.599° W, 14/May/2007, #170, JK Wetterer; market shop, St George’s Church, 17.131° N, 62.571° W, 16/May/2007, #215, JK Wetterer ; PUERTO RICO: Vieques: Bunkers, 0.7 km SW bunker 309, 8/Jun/2006, #321, JK Wetterer; Vieques: Playa Grande, sea grape, 18.092° N, 65.509° W, 7/Jun/2006, #319, JK Wetterer ; Vieques: Mosquito, S of pier, 18.130° N, 65.510° W, 8/Jun/2006, #334, JK Wetterer; San Juan, international airport, 16/May/2006, #7, JK Wetterer; ST. KITTS: Bayford’s, near radio tower, 17.327° N, 62.731° W, 6/May/2007, #32, JK Wetterer; Wingfield, forest by orchard, 17.334° N, 62.801° W, 8/May/2007, #85, JK Wetterer; Camp Bay, scrub N of PR, 17.298° N, 62.751° W, 8/May/2007, #81, JK Wetterer; Rawlins, Plantation, 17.401° N, 62.828° W, 7/May/2007, #53, JK Wetterer; Boguis forest, 17/Nov/2003, #57, JK Wetterer ; ST. LUCIA: Ambre, 4.4 km E of 52, 16/Nov/2003, #53, JK Wetterer; Prasin, 16/Nov/2003, #48, JK Wetterer; Choc, 15/Nov/2003, #45, JK Wetterer ; ST. MARTIN: La Colombe, Rue de Concordia, 18.062° N, 63.074° W, 24/May/2006, #129, JK Wetterer; French Cul de Sac pasture, 18.107° N, 63.029° W, 23/May/2006, #120, JK Wetterer ; La Soufriere trail, trailhead parking, 13.318° N, 61.156° W, 5/Jul/2006, #707, JK Wetterer; Rickmond Bach SW end of beach, 13.319° N, 61.236° W, 1/Jul/2006, #608, JK Wetterer; TRINIDAD: Blanchisseuse Rd, 4 km N Asa Wright, 30/Oct/2003, #213, Wetterer; Victoris Mayare Res., 7 km N gate, 3/Nov/2003, #234, Wetterer; Palmiste, 21/May/2004, #24, JK Wetterer; North Coast Rd, 6 km of Saddle, 30/Jun/2004, #474, JK Wetterer; 2 km NW Howson, 10/Jul/2004, #488, JK Wetterer; 10 km S Rte Clare, 31/Jul/2004, #541, JK Wetterer; Blanchisseuse Rd, 1 km S Asa Wright, 30/Oct/2003, #211, Wetterer; Victoria Mayare Res. 2 km W gate, 3/Nov/2003, #232, Wetterer; Mt Hope, 21/May/2004, #418, JK Wetterer; North Coast Rd, 6 km 2004, #474, JK Wetterer; 2 km SW Cunaripa, 10/Jul/2004, #487, JK Wetterer ; TOBAGO: Tobago Forest Res., Gilpin Trace, 14/Oct/2003, #192, Wetterer ; U.S. VIRGIN ISLANDS: St Croix, Springfield, 76; 0.5 Km W quarry, 17.732° N, 64.834° W, 9/March/2006, #235, JK Wetterer; St. Croix, Jolly Hill, E of 763; N of 76, 17.732° N, 64.861° W, 3/March/2006, #35, JK Wetterer ; St. John, Bordeaux Mtn, 0.5 Km E of peak, 18.339° N, 64.734° W, 9/Nov/2005, #299, JK Wetterer; St. Thomas, Mountaintop by mall, 18.356° N, 64.947° W, 8/Nov/2005, #270, JK Wetterer ; St. Thomas, Botany Bay, 1 km N of 30, 18.357° N, 65.027° W, 6/Nov/2005, #245, JK Wetterer .

Notes: Trager (1984) considered two morphological differences to separate N. steinheili and N. steinheili minu- ta into distinct species. He noted that the subbasal tooth (tooth 5 counting from apical to basal) in N. steinheili is always small relative to the median tooth (tooth 4 counting from apical to basal). Whereas, there are other specimens were the subbasal tooth is distinctly large relative to the median tooth and these would be distinguishable as N. steinheili minuta . Differences in coloration were also noted, with N. steinheili minuta having the mesocoxae and metacoxae reddish, and N. steinheili with mesocoxae and metacoxae that are bright white. Initially, we were able to separate specimens using the above morphological criteria, but the more specimens we examined the more difficult it became as both morphological characters showed considerable variability. Therefore, until other data becomes available we consider N. steinheili minuta a synonym of N. steinheili .

Nylanderia steinheili is a widespread species, which may or may not be native to the West Indies. There is considerable morphological variation in what we are calling N. steinheili . This species is putatively found in Central and South America as well so it is hoped that as revisions of Nylanderia in those regions are completed further data for better refinement of the morphological limits of this species will be possible.

Nylanderia steinheili and N. guatemalensis are broadly sympatric across the West Indies with both occurring primarily in similarly disturbed habitats. Usually both can be separated relatively easily based on worker body coloration, with N. steinheili being dark brown to black and N. guatemalensis being yellow to light brown (typically with contrasting dark macrosetae). However, particularly in southern Florida and the Bahamas, N. guatemalensis can have a darker body, sometimes approaching dark brown. This can make distinguishing the species difficult. N. guatemalensis and N. steinheili both occur in Florida in contrast to Kallal and LaPolla (2012) which only reported N. steinheili . Apparently, N. guatemalensis occurs only in the extreme southern part of the state, whereas N. steinheili is more widespread. We found N. guatemalensis workers have a SI above 120 while N. steinheili worker have a SI below 120, but there is some overlap. Like N. steinheili, N. guatemalensis putatively ranges into Central and South America.

We did examine the penial sclerites for both N. steinheili and N. guatemalensis males (fig. 105). Overall the penial sclerites are fairly similar in basic structure but there are some importance differences. The anteroventral process of N. steinheili is emarginate, whereas in N. guatemalensis it is broadly rounded. Additionally, the penial sclerite vulvurae are ventrally placed in N. steinheili; in N. guatemalensis they are at the midline of the penial sclerites. As in worker morphology, the male morphology suggests these species are closely related, perhaps even sister taxa. It is important to note we examined a relatively small number of males and both of these species range far outside of the West Indies where male morphology needs to be examined as well.