Lucas & Stange': Florida Myrmeleon Larvae 207

KEY AND DESCRIPTIONS TO THE MYRMELEON LARVAE OF FLORIDA (: MYRMELEONTIDAE) 1

J"EFFREY R. LUCAS2 AND LIONEL A. STANGE3

ABSTRACT Descriptions of the 3rd instar larva of 5 of the 6 species of Myrmeleon found in Florida are given. Only M. immaculatus De Geer has been described previously. Myrmeleon insertus Hagen is a new record for the state. A key to the species is provided with the diagnostic characters (chaetotaxy of the mandible; pigmentation pattern of the ventral surface of the head) illus­ trated.

RESUMEN Clave y descripciones de las larvas de Myrmeleon de Florida. Se describe el tercer estadio de las larvas de cinco de las seis especies floridanas. Son M. carolinus Banks, M. crudelis Walker, M. immaculatus De Geer, M. insertus Hagen, y M. mobilis Hagen. La larva de M. heriocles Hagen es desconocida. Se presentan dibujos y una clave para las especies basada sobre las setas de la mandibula y la pigmentacion de la superficie ventral de la capsula cefalica.

Five species of the -lion genus Myrmeleon have been recorded from Florida. These are immac'uJatus De Geer, mobilis Hagen, crudelis Walker, heriocles Banks, and carolinus (Banks 1928, 1943). In addition, we add to the list a sixth species, insertus Hagen, known only from the Florida Keys and the West Indies. The larvae construct pit-fall traps and can move only backward, be­ havioral traits which distinguish them from all other ant-lion larvae in Florida. Structurally, the short labial palps (shorter than basal width of mandible) and the long 3-toothed mandibles with long setae between the teeth (Fig. 1) serve to distinguish them from other genera in Florida (Stange 1970). Only the larva of immaculatus has been described (Hagen 1873, Wheeler 1930). In this paper we provide descriptions and drawings to distinguish 5 of the 6 known species (heriocles is unknown in the larval stage). Myr1neleon carolinus, crudelis, mobilis, and insertus have been reared several times from various localities in Florida, but immaculatus has been found only as an adult; the larval description is based on material from other states. All specimens examined are preserved in the Florida State Collection of , Gainesville.

l.A joint contribution of the University of Florida~ Depart:ment of Zoology, Gainesville, and the Florida Dept. of Agr. and Consu:mer Services, Division of Plant Industry. Contribution No. 489, Bureau of Ento:mology~ DPI. 2University of Florida~ Depart:ment of Zoology, Gainesville, FL 32611 USA. 3Florida Department of Agriculture and Consu:mer Services, Division of Plant Industry. Gainesville, FL 32602 USA. ot\J 00

TABLE 1. HEAD MEASUREMENTS OF Myrmeleon LARVAE FROM FLORIDA. ALL LENGTHS ARE MEAN VALUES GIVEN IN MM WITH STANDARD DEVIATION IN PARENTHESES. SETAE NUMBERS ARE MEAN VALUES WITH RANGES IN PARENTHESES.

~ Head Head ~ 0 # Setae- # Setae- # Setae- width/ width/ ~ Mandible Head Head jaw to 1st to 2nd to Mand. Head Species Instar N length width length 1st tooth 2nd tooth 3rd tooth width length ~ ~ ~ ~ insertus 3 7 1.63 (.08) 1.31 (.05) 1.76 (.01) 3 (2 .. 6) 0(0) 0(0) 0.80 0.74 0 insertus 2 3 0.99 (.01) 0.81 (.01) 1.07 (.01) 0(0) 0(0) 0(0) 0.82 0.76 ~ 0 crude lis 3 36 1.75 (.06) 1.38 (.07) 1.86 (.10) 8 (3 .. 12) 0(0-1) 0(0) 0.79 0.74 ~ 0 crude lis 2 20 1.11 (.04) 0.88(.04) 1.17 (.05) 2 (0-5) 0(0) 0(0) 0.79 0.75 ~ crude lis 1 7 0.76 (.04) 0.55 (.03) 0.69 (.05) 0(0) 0(0) 0(0) 0.72 0.80 ~. carolinus 3 21 ' 1.58 (.03) 1.40 (.03) 1.82 (.07) 11 (6-18) 4 (2 .. 7) 2 (0-6) 0.89 0.77 C"'I- ~ carolinus 2 17 1.08 (.04) 0.89 (.03) 1.15 (.03) 5 (2-7) 2 (2-4) 1 (0-2) 0.82 0.77 ~ ~ carolinus 1 12 0.70 (.01) 0.54 (.01) 0.65 (.02) 0(0) 0(0) 0(0) 0.77 0.83 l\j mobilis 3 18 2.37 (.13) 1.77 (.10) 2.20 (.14) 0(0) 0(0) 0(0) 0.75 0.80 'wi mobilis 2 17 1.55 (.09) 1.15 (.02) 1.47 (.07) 0(0) 0(0) 0(0) 0.71 0.77 mobilis 1 15 1.03 (.03) 0.71 (.02) 0.87 (.04) 0(0) 0(0) 0(0) 0.69 0.82 immaculatus 3 3 2.54 2.05 2.38 3 (1-4) 0(0) 0(0) 0.81 0.86 from Ohio & Missouri c....r ~ =CD ~

~ (0 00 ~ Lucas & Stange: Florida Myrmeleon Larvae 209

Inner Jaw Setae

~~~p------Distal Palpomere with Sensory Area

Fig. 1. Ventral view of head capsule of Myrmeleon (modified from Principi 1943).

From the 1st to 3rd instar the ratio of head width to mandible length generally increases for all species, and the ratio of head width to head length generally decreases. Thus, earlier instars have relatively longer mandibles and stouter heads than later instars. The following descriptions pertain to the 3rd instar, the last before pupa­ tion.

METHODS Specimens were examined from 36 locations representing 21 different counties in Florida. Larval specimens of M. immaculatu8 were studied from Missouri and Ohio. We reared specimens of carolinus (89 reared), crudelis 133 reared), mobilis (66 reared), and insertus (8 reared). To characterize 210 Florida Entomologist 64 (2) June, 1981 differences between species in size and shape of the head, we measured head width, head length, and mandible length (Table 1). Head width was taken near the mandibles where the width was maximum. Head length was meas­ ured from the point mid-way between the mandible bases to the median posterior point of the head. Mandible length was measured from the tip of the right mandible to its inner base. We also describe setation patterns from the ventral side of the mandibles that are species specific. These setae, which we call inner jaw setae (Fig. 1), are found on the inner side of the mandi­ bles near the teeth. These setae originate from the ventral side of the mandi­ ble. All ant-lions have setae originating from the lateral inner border. All counts are given for the right mandible. The 3 teeth on the inside of the jaw are numbered 1-3, starting from the tooth nearest the base of the mandible (as in Dofiein 1916). We studied 166 larvae of carolinus, 168 of crudelis, 106 of mobilis, and 19 of insertus. Nine specimens of immaculatus from Ohio and Missouri were studied to provide tentative identification, although Florida specimens are needed to confirm the pigment pattern.

RESULTS AND DISCUSSION Five species of ant-lions were examined: M. immaculatus, mobilis, crude lis, carolinus, and insertus. The 6th species, heriocles, which is known only from a few adult specimens, was not available as a larva and is not in­ cluded in this study. The character that most easily distinguishes the species is the pigmenta­ tion on the ventral side of the head. Although one basic pattern is found in all species, each exhibits a unique variation. The pattern consists of a V-shaped mark below the labium with 2 spots, 1 on either side of the head, belo"\v the "V" (Fig. 2-5). The pattern for each species is described below with the species descriptions. Banks (1928, 1943) separated immaculatus and mobilis from crude lis and carolinus adults on the basis of several morphological characters, including size. Inse'rtus is approximately the same size as crudelis and thus the 5 spe­ cies can be broken into large (mobilis and immaculatus) and small (insertus, carolinus, and crude lis ) ant-lions. In general, the color patterns on the ventral side of the head are retained through all 3 instars. Occasionally, the head of the 1st instar carolinus is entirely black below and black with a median tan stripe dorsally. The number of inner jaw setae increases as the ant-lion grows from 1st instar through the 3rd instar, and therefore this character is useful in distinguishing only the 3rd instar (Table 1).

Myrmeleon carolinus Banks 1943 (Fig. 2)

DESCRIPTION: Head oval-shaped, more elongate than other species. Head width (1.40 mm) approximately equal to that of crudelis, smaller than im­ maculatus and mobilis. Mandibles shorter and broader than those of other species. Inner jaw setae always extend past the 1st tooth and usually past the 2nd (Table 1). Setae on head, especially lateral and ventral, shorter than all other species. Lucas & Stange': Florida Myrmeleon Larvae 211

PIGMENTATION: Head and mandibles brown.; Ventral and dorsal side of body with rows of black pigment on gray background. Ventral side of head: "V'" broad with rounded tips, arms separated. Spots large and circular, generally well defined. Lighter pigmentation from "V" to spots forms "M" shape (Fig. 2). Dorsal side of head: Almost entirely dark brown. Median tan stripe in posterior portion and 2 "V"-shaped tan marks behind each eye. DISTRIBUTION: Found throughout North and Central Florida. We have rec­ ords only as far south as Highlands County. Banks (1943) reported carolinus from Florida, Georgia, and North Carolina. M. carolinus is generally found

2 Fig. 2. Ventral view of head capsule of Myrmeleon carolinus Banks. 212 Florida Entomologist 64 (2) June, 1981 in open, sandy areas, although it is occasionally collected in sheltered areas with crudelis. SPECIMENS EXAMINED: FLORIDA: Alachua Co., Gainesville (12) III, V, X, various collectors; Bay Co., St. Andrews State Park (10) 8-111-1980, B. Miller & L. Stange; Dixie Co., 4 miles north Old Town (7) 1-V-1980, J. Lucas & L. Stange; Highlands Co., Archbold Biological Station (4) 13-111-1980, B. Miller & L. Stange, 5 miles south Sebring (15) 12-111-1980, B. Miller & L. Stange; Franklin Co., Carrabelle (6) 10-IV-1978, L. Stange; Okaloosa Co., 2 miles north Holt (3) 7-111-1980, B. Miller & L. Stange; St. Johns Co., Fort Matanzas (2) 7-VII-1978, L. Stange, Ponte Vedra Beach (11) 7-VII-1978, L. Stange.

Myrmeleon crudelis Walker 1852 (Fig. 3)

DESCRIPTION: Head somewhat rectangular with lateral indentations, simila110 in shape to insertus. Head capsule width (1.38 mm) approximately same size as carolinus, and smaller than mobilis and immaculatus. Mandible length to head width ratio as well as head width to head length ratio almost identical

Fig. 3-4. Ventral view of head capsules; 3. Myrmeleon crudelis Walker, 4. M. insertus Hagen. Lucas & Stange: Florida Myrmeleon Larvae 213 to insertus. Average of 8 inner jaw setae from mandible base to 1st tooth. Generally none past 1st tooth. Head relatively long. PIGMENTATION: Head and mandibles light brown to tan. Dorsal and ventral body with rows of black spots on pink to light brown background. Ventral side of head: "V" arms bar-shaped, not attached at base. Spots elongate and angled toward "V". Pigment patterns very distinct (Fig. 3). Dorsal side of head: Posterior portion dark brown with 4 large parallel bars. Anterior light brown with 2 dark triangular spots behind antennae, entire area be­ tween antennae dark. DISTRIBUTION: Found throughout Florida from the Panhandle to Dade and Collier counties. Not found in the Florida Keys. Banks (1928) reported crudelis from Florida, Georgia, New Jersey, North Carolina, Texas, and Virginia. This species is generally found in sheltered areas in a variety of soil types, although it is occasionally collected in open areas where carolinu8 is abundant, often collected with mobilis. SPECIMENS EXAMINED: FLORIDA. Alachua Co., Gainesville (29) year round; Collier Co., Marco Island (20) 9-IV-1952, R. E. Woodruff; Dade Co., Matheson Hammock (8) 14-11-1978, L. Stange, Miami (2) 4-IV-1980, L. Stange; Dixie Co., 4 miles north Old Town (9) 1-1-1980, J. Lucas & L. Stange; Highlands Co., Archbold Biological Station (1) 13-111-1980, B. Miller & L. Stange, 5 miles south Lake Placid (4) 21-111-1978, L. Stange, Highlands Hammock (14) 4-111-1978, L. Stange; Hernando Co., Bayport (2) 22-IV-1978, L. Stange; Franklin Co., Alligator Point (5) 9-IV-1978, L. Stange; Indian River Co., Sebastian (2) 25-1-1962, H. Weems; Lee Co., Sanibel Island (3) 20-IV-1978, L. Stange; Levy Co., Seahorse Key (5) 10- III-1980, J. Lucas & L. Stange; Martin Co., Jonathan Dickinson State Park (4) 15-11-1978, L. Stange; Pasco Co., Bayonet Pass (9) 22-IV-1978, L. Stange; Pinellas Co., Tierra Verde (1) 5-VII-1978, L. Stange; St. Johns Co., Fort Matanzas (3) 7-VII-1978, L. Stange.

Myrmeleon insertus Hagen 1861 (Fig. 4)

DESCRIPTION: Head somewhat rectangular with lateral indentations, very similar in shape to that of crudelis. Head capsule width (1.31 mm) smallest of the 5 species but similar to crudelis and carolinus. Mandible length to head width ratio and head width to head length ratio almost like crude lis. Average of 3 inner jaw setae near the mandible base, none past the 1st tooth (Table 1). Head setae very long compared to other species. PIGMENTATION: Head and mandibles light brown to tan. Ventral and dorsal body with rows of black spots on pink to light brown background. Ventral side of head: "V" short and blunt, arms not attached but each arm often connected to elongated and bar-shaped spots. Together they form an "R" shape (Fig. 4). Dorsal side of head: Posterior portion dark brown with 4 large parallel bars. Anterior light brown with 4 dark round spots, forming a "Y" shape between antennae, with base of "Y" pointing anteriorly. DISTRIBUTION: In Florida, insertus is known only from the Florida Keys. Specimens were collected in sheltered sandy soils. It is also recorded from Cuba (Hagen 1861, Alayo 1968), Haiti (Smith 1931), and the Dominican Republic (Hagen 1861). SPECIMENS EXAMINED: FLORIDA. Monroe Co., Big Pine Key (4) 24-111- 214 Florida Entomologist 64 (2) June, 1981

1978, L. Stange, Ramrod Key (4) 25-111-1978, L. Stange, Bahia Honda Key (11) 22-XI-1980, L. Stange. Myrmeleon mobilis Hagen 1888 (Fig. 5) DESCRIPTION: Head generally square with slight lateral indentations. Head stouter than carolinus, crudelis, and insertus. Head width (1.77 mm) larger than carolinus, crude lis, and insert-ups, and somewhat smaller than im­ maculatus. In relationship to head width, mandibles are the longest of the 5 species. Inner jaw setae entirely absent (Table 1). Setae on head longer than those of carolinus but proportionately shorter than crudelis and insertus. PIGMENTATION: Head and mandibles light brown to tan. Dorsal and ventral body with rows of dark pigment on light brown background. Ventral side of body: "V" broad at base, arms often connected, tips pointed. Spots generally diffuse (Fig. 5). Dorsal side of head: Lighter than crude lis, carolinus, and insertus. Four widely spaced blotches located posteriorly with 4 spots anterior to blotches. Posterior 2 spots triangular as in crude lis, anterior most spots are "T"-shaped. DISTRIBUTION: We have records from the Panhandle south to Collier County. Not found in the Florida Keys. Banks (1928) reported mobilis from Alabama

6

Fig. 5-6. Ventral view of head capsules; 5. Myrmeleon mobilis Hagen, 6. M. immaculatus De Geer. Lucas & Stange: Florida Myrmeleon Larvae 215

and Georgia. Myrmeleon mobilis is generally found in finer soils in sheltered areas, often collected with crudelis. SPECIMENS EXAMINED: FLORIDA. Alachua Co., Archer (1) l-VIII-1967, P. Choate, Gainesville (15) 1-V-1980, J. Lucas & L. Stange; Highlands Co., Archbold Biological Station (5) 23-111-1978, L. Stange, Highlands Hammock (3) 4-111-1978, L. Stange, 5 miles south of Lake Placid (1) 21-111-1978, L. Stange; Jackson Co., Florida Caverns (10) 14-IV-1978, L. Stange; Okaloosa Co., 4 miles north Holt (3) 17-IV-1978, L. Stange. De Geer 1773 (Fig. 6) Hagen 1873: 291. Wheeler 1930: 99, Fig. 13. DESCRIPTION: Head square, more so than in mobilis, ratio of width to length highest of the 5 species. Head width (2.05 mm) largest of all species. Mandi­ bles intermediate in length, not so long (in proportion to head) as mobilis. Average of 3 inner jaw setae near the base of the mandibles (Table 1). Setae on head short but not as short as carolinus. PIGMENTATION: Head and mandibles light brown to tan. Ventral and dorsal sides of body with rows of black pigment on pink to light brown background. Ventral side of head: Less pigmentation than other species. "V" very short, forms 2 almost round bars. Spots elongate, pointing toward "V" (Fig. 6). Dorsal side of head: Three prominant black spots, 1 between the antennae and 2 side by side between them. Two other lighter pigmented areas behind the black spots. DISTRIBUTION: Found only in the northernmost parts of Florida. Myrmeleon immaculatus has one of the most restricted distributions of ant-lions in Florida, but it is widely distributed in North America, found throughout the eastern U.S. and southeastern Canada (Banks 1928). SPECIMENS EXAMINED: OHIO. Hocking Co. (2) 1-V-1954, T. V. Wallace; Ottawa Co. Rockyridge (1) 30-IX-1972, J. Balciunas; MISSOURI. Boone Co., Columbia (3) 11-VIII-1967, S. L. Poe; Marion Co. (3) 24-VII-1972, C. Childers.

Key to 3rd Instar Larvae of Myrmeleon of Florida 1. Mandible without inner jaw setae (Fig. 5) ; head width greater than 1.6 mm ------______mobilis Hagen 1'. Mandible with inner jaw setae (Fig. 2-4, 6) ; head width less than 1.6 mm (except immaculatus) ______2 2. Mandible with inner jaw setae extending to or beyond 2nd tooth (Fig. 2) ; head much darker than grayish body ______corolinus Banks 2 (1'). Mandible with inner jaw setae extending no further than 1st tooth; head coloration similar to that of light tan body ______3 3. Pigmentation on ventral side of head with anterior set of bars tilting toward center usually forming a "V" (Fig. 3) ; mandible with inner jaw setae (usually more than 6) extending almost to 1st tooth ------______crudelis Walker 3 (2'). Pigmentation on ventral side of head forming "H" mark (inse'rius) or much reduced (intmaculatus); mandible with inner jaw setae (often less than 6) not extending to 1st tooth __ ._. _____ 4 216 Florida Entomologist 64 (2) June, 1981

4. Pigmentation on ventral side of head forming "H" mark (Fig. 4) ; head width less than 1.6 mm ______i-nsertus Hagen 4 (3'). Pigmentation on ventral side of head much reduced (Fig. 6) ; head width more than 1.6 mm ______immaculatus De Geer

ACKNOWLEDGEMENT The authors are indebted to Ms. Tina Pellicane for the preparation of Figures 2-6.

LITERATURE CITED ALAYO, P. 1968. Los Neur6pteros de Cuba. Poeyana (B) No.2: 5-127. BANKS, N. 1928. Revision of the nearctic Myrmeleonidae. Bull. Mus. Comp. Zool. 68 ( 1927): 3-84. --. 1943. New Neuroptera and Trichoptera from the United States. Psyche 50: 74-81. DOFLEIN, F. 1916. Der Ameisenlowe. Eine Biologische, Tierpsychologische und Reflexbiologische Untersuchung. Jena, Gustav Fischer, p. 1-138, Tab.1-x. HAGEN, H. 1861. Synopsis of the Neuroptera of North America "\vith a list of the South American species. Smithsonian Misc. CoIL, p. 1-347. ---. 1873. Die Larven von Myrmeleon. Stettin ent. Ztg. 34: 249-95. ---. 1888. Stray notes on the Myrmeleonidae, Part. 5. Canadian Ent. 20: 204-11. MOODY, H. L. 1873. Notes on the habits of the ant lion. Canadian Ent. 5: 63-5. PRINCIPI, M. 1943. Contributi allo studio dei N eurotteri italiania. II. Myrmeleon inconspicuus Ramb. ed Euroleon nostras Fourcroy. Boll. Ist. Ent. Univ. Bologna 14: 131-92. REDTENBACHER, J. 1884. Ubersicht der Myrmeleoniden-Iarven. Denk. Ak. Wien 48: 335-68, pI. i-vii. SMITH, R. 1931. The Neuroptera of Haiti, West Indies. Ann. Ent. Soc. America 24: 798-823. STANGE, L. A. 1970. Revision of the ant-lion tribe Brachynemurini of North America. Univ. California PubI. Ent. 55: 1-192. WALKER, F. 1853. List of the N europterous insects in the collection of the British Museum. Part II (Sialidae-Nemopterides). London, p. 193-476. WHEELER, W. M. 1930. Demons of the Dust. W. W. Horton & Co., New York, 378 p. Bibliography of the Neuropterida

Bibliography of the Neuropterida Reference number (r#): 3776

Reference Citation: Lucas, J. R.; Stange, L. A. 1981 [1981.??.??]. Key and descriptions to the Myrmeleon larvae of Florida (Neuroptera: Myrmeleontidae). Florida Entomologist 64:207-216.

Copyrights: Any/all applicable copyrights reside with, and are reserved by, the publisher(s), the author(s) and/or other entities as allowed by law. No copyrights belong to the Bibliography of the Neuropterida.

Notes:

File: File produced for the Bibliography of the Neuropterida (BotN) component of the Lacewing Digital Library (LDL) Project, 2015.