Matsucoccus gallicolus Morrison, 1939

Ahmed, Muhammad Z., Ray, Charles H., Moore, Matthew R. & Miller, Douglass R., 2020, The Matsucoccus Cockerell, 1909 of Florida (Hemiptera: Coccomorpha: Matsucoccidae): Potential pests of Florida pines, Insecta Mundi 2020 (810), pp. 1-31 : 15-22

Matsucoccus gallicolus Morrison, 1939

( Fig. 9–10 )

Matsucoccus matsumurae (Kuwana) ; Herbert 1921: 15. misidentification ( Morrison 1939: 9–13) (in part; also see M. alabamae ).

Matsucoccus sp.; Parr 1939: 624–630.

Matsucoccus gallicolus Morrison 1939: 9 . Accepted valid name.

Adult Female

( Fig. 9 )

Diagnosis. Cicatrices numbering less than 310, present on segment I to segment VI; cicatrices absent from near body margin; with fewer than 30 multilocular pores; body setae of two distinct sizes; fleshy setae present on distal four antennal segments.

Description. Body elongate, parallel sided, 2.2–4.5 mm long, 1.0–2.7 mm wide. Dorsum: Setae uncommon, inconspicuous, arranged in rows, of one size, 5–8 µm long. Bilocular tubular ducts scattered over surface, uncommon on head and within rows of cicatrices; tubes usually slightly divergent. Cicatrices on segment I–VI; cicatrices present in medial and mediolateral areas, absent near body margin; some anterior segments with separate rows on anterior and posterior sections, anterior rows usually with fewer cicatrices; with 170–378 cicatrices; largest 6–12 µm in diameter.

Venter. Setae uncommon, arranged in rows, of two sizes, smaller setae 5–12 µm long, over most of surface; longest seta anterior of hind coxae 40–55 µm long, longer setae also present in medial areas of abdominal segments. Bilocular tubular ducts arranged segmentally, uncommon on head, most abundant on margin; similar in size and shape as on dorsum or slightly smaller. Multilocular pores in cluster around vulva, most specimens with ventral vulva located at or near abdominal apex; with 20–32 multilocular pores; diameter of largest pore 9–15 µm. Thoracic spiracles without definite sclerotized rim on derm or with narrow band of sclerotization; posterior spiracle with largest diameter of atrium 22–30 µm; with seven pairs of abdominal spiracles, normally with dermal orifice sclerotized, more weakly sclerotized posteriorly, sometimes decreasing in size posteriorly, diameter of dermal orifice of first abdominal spiracle 12–18 µm, of seventh spiracle 8–20 µm. Legs large and conspicuous, with scale-like pattern on all segments except first tarsal segment; hind leg with trochanter with one long seta, 7–10 sensoria; femur 190–260 µm long, with 8–18 setae; tibia 172–310 µm long, with 22–40 setae; tarsus (both segments) 115–170 µm long, tarsal digitule undifferentiated; claw without denticle, with two conspicuous digitules, equal in size. Antennae nine segmented, 0.4–0.9 mm long; apical four segments each with two enlarged setae; first segment 100–155 µm long, 90–160 µm wide, with 5–8 setae on ventral surface, 18–31 setae on dorsal surface; second segment 62–100 µm long, 75–100 µm wide, with 5–8 setae on ventral surface, 5–8 setae on dorsal surface.

Material examined. Alabama, near Birmingham, April 13, 1929, on Pinus virginiana, E.J. Palmer (35332) 1 adult ♀ (paratype). Connecticut: New Haven, received October 26, 1937, on Pinus rigida, R.C. Brown , 3 adult ♀. Georgia: St. Mary’s River, May 1, 1921, on Pinus glabra , unknown collector (39 1510), 3 cysts, 1 adult ♀ (paratype). Maryland: Beltsville , received September 23, 1946, on Pinus rigida, St. George (Hopkins 34109), 3 adult ♀ ; Berlin , September 20, 1970, on Pinus taeda, D.R. Miller , 5 adult ♀ ; Cambridge, March 14, 1971, on Pinus taeda, D.R. Miller , 3 adult ♀. Massachusetts: Amherst , June 9, 1946, on Pinus rigida, W.B. Becker , (46 795) 4 adult ♀ ; Cape Cod , November 5, 1935, on Pinus rigida, W. Becker , 1 adult ♀ (paratype) ; Sandwich, June 9, 1916, on Pinus rigida, Fernald and Hun , 4 adult ♀ (paratype). Missouri: near Tecumseh , N. fork of White River , Ozark Co., October 7, 1927, on Pinus echinata, E.J. Palmer (30893) 1 adult ♀, 1 cyst (paratype). New Hampshire: Nashua , May 27, 1937, on Pinus rigida, T. Parr , 3 adult ♀, 3 cysts, 1 first-instar nymph (paratype). New Jersey: between Tom’s River and Tuckerton, February 18, 1937, on Pinus rigida?, Mr. May, 2 adult ♀ ; Barnegat, July 22, 1936, on Pinus rigida, R.R. Whitten , 2 adult ♀. New York: Centerport , December 1, 1919, on Pinus rigida, J.T. Morton , (Hopkins 16404A) 1 adult ♀ (paratype) ; Centerport , August 25, 1919, on Pinus rigida, L.C. Griffith , 1 adult ♀, 2 cysts (paratype) ; Great River, September 25, 1953, on Pinus rigida, G.V. Johnson ( T.C. # 116) 2 adult ♀, 6 cysts. North Carolina: Ashville , May 8, 1937, on Pinus rigida or P. echinata, B.H. Wilford , (39 1506) 2 adult ♀ (paratype). Ohio: Delaware, received for identification December 2, 1970, on Pinus rigida, J.B. Hanson (70-23862), 4 adult ♀ ; Pennsylvania: State Forest Park, Mont Alto , September 1935, on Pinus rigida, J. C. Kase , 1 ad ♀, 3 first-instar exuviae, 3 cysts (paratype) ; Mont Alto , September 18, 1935, on Pinus rigida, J. C. Kase , 1 adult ♀ (paratype) ; Mont Alto, Januaruy 30, 1937, on Pinus echinata , collector unknown, 5 adult ♀, 1 3 rd ♂ (paratype); Mont Alto, Guilford Turnpike , March 1937, on Pinus rigida, J. C. Kase , 1 adult ♀ (paratype) ; South Carolina: Cooper River, Charleston, April 4, 1909, on Pinus taeda, J.G. Sanders , 1 3 rd ♂. Virginia: Falls Church , Franklin Park , April 20, 1936, on Pinus virginiana, I. Weckerly , 2 adult ♀, 2 cysts (paratype) ; Glouchester , unknown location, January 5, 1968, on Pinus virginiana (witches broom) C.L. Morris, 1 adult female ; Gouchland County, locality unknown, on pine, collector unknown 1 3 rd ♂ ; Princess Anne County, May 1898, on Pinus taeda, T.H. Kearney, Jr. , ( USNM 355800 ), 1 adult ♀, 1 cyst (paratype) ; Rockbridge County, October 31, 1941, on Pinus rigida, M.C. Howard (41 2603), 5 adult ♀, 3 cysts. Washington, D.C., Good Hope Hill , March 19, 1905, on Pinus virginiana, J.G. Sanders , 1 adult ♀ ; Good Hope Hill , May 11, 1936 & March 19, 1905, on Pinus virginiana, L.M. Russell (39 1498), 7 adult ♀ .

Remarks. Adult females of M. gallicolus can be separated from adult females of M. krystalae (characters in parentheses are of M. krystalae ) as follows: With 170–378 cicatrices (437–900); cicatrices absent from marginal areas (marginal cicatrices present on one or more of segments IV–VI); with 20–32 multilocular pores (36–72); vulva and multilocular pores usually at or near posterior apex of abdomen (many specimens with vulva and multilocular pores located under dorsum of segment IV or V).

The above description is based on 52 specimens from 23 localities.

Third-instar Male

( Fig. 10 )

Diagnosis. Two sizes of setae on venter, setae anterior of metacoxae about 20 µm long, marginal setae about 5 µm long; with less than eight bilocular tubular ducts on dorsum of abdominal segment III; abdominal spiracles usually decreasing in size posteriorly; fleshy setae present on distal four antennal segments.

Description. Body elongate, 1.1–1.9 mm long, 0.7–1.1 mm wide. Dorsum: Setae uncommon, inconspicuous, arranged in rows, of one size, about 5 µm long. Bilocular tubular ducts scattered over surface, in segmental rows, associated with setal rows, not arranged in longitudinal lines; with less than eight ducts on abdominal segment III, tubes fused.

Venter. Setae uncommon, arranged in rows, of two sizes, larger 18–20 µm long, smaller about five µm long; longest seta anterior of hind coxae about 20 µm long. Bilocular tubular ducts uncommon on head and medial areas of thorax, most abundant on margin, arranged in longitudinal lines, present submedially and laterally; similar in size and shape as on dorsum, of two variable sizes. Thoracic spiracles without definite sclerotized rim on derm; posterior thoracic spiracle with largest diameter of atrium 15–25 µm; with seven pairs of abdominal spiracles, normally with dermal orifice sclerotized, all equally sclerotized, normally decreasing in size posteriorly, diameter of sclerotized rim of dermal orifice of first abdominal spiracle 12–17 µm, of seventh spiracle 6–10 µm. Legs large and conspicuous, with scale-like pattern on all segments except first tarsal segment; hind leg with trochanter with one long seta, sensoria hidden by bend; femur 125–195 µm long, with 4–7 setae; tibia 92–177 µm long, with 20–32 setae; tarsus (both segments) 77–102 µm long, tarsal digitule undifferentiated; claw without denticle, with two conspicuous digitules, equal in size. Antennae nine segmented, 0.4 mm long; apical four segments each with two enlarged setae; first segment 100 µm long, 88 µm wide, with two setae on ventral surface, 12 setae on dorsal surface; second segment 50 µm long, 67 µm wide, with three setae on ventral surface, three setae on dorsal surface, four sensilla on dorsal surface. Ventral developing genitalia located near posterior apex of abdomen.

Type material. Type data: USA: Pennsylvania, Stroudsburg, farm of Mrs. E. Bethel, on Pinus rigida , April 1936, collected E.C. Pyle. Holotype, female, Type depository: Washington: United States National Entomological Collection, U.S. National Museum of Natural History , District of Columbia, USA ( USNM). Accepted valid name. We have examined the holotype and several of the paratypes. There is a long series of paratypes from many eastern states.

Remarks. Third-instar males of M. gallicolus can be separated from M. krystalae (characters in parentheses are of M. gallicolus ) as follows: 10 or more bilocular tubular ducts on dorsum of abdominal segment III (fewer than 8). Third-instar males of M. gallicolus can be separated from M. alabamae (characters in parentheses are of M. gallicolus ) as follows: setae anterior of hind coxa and in medial area of abdomen about same size as other body setae (setae in these areas conspicuously longer than other body setae).

The above description is based on three third-instar males from three localities. The specimens used for this description are in poor condition; some still have their antennae and legs compacted in dermal pockets causing many of the characters to be difficult to discern.

Life history. The following information is from Parr (1939). The species overwinters as eggs in the ovisac which are usually located under the bark on branches of the pine host. Hatching occurs in late April in Connecticut and Pennsylvania when the new growth on the pine terminals is one to three inches long. Immediately after hatching the dark yellow crawlers move to the new growth, insert their mouthparts, and begin feeding. After continued feeding, the body of the crawler gradually turns dark brownish black and the integument around the mouthparts begins to swell. There is concomitant degradation of plant tissue around the base of the stylets and the ventral surface of the crawler sinks into the cavity in the plant. There also is slight swelling of the plant tissue around the outside of the crawler that continues until the body of the crawler is almost completely enclosed. After six to nine weeks from hatching, the crawler molts to the second-instar cyst. The shed skin of the crawler is usually trapped in the hole in the epidermis of the plant and the cyst is totally encapsulated in plant tissue except for the hole where the shed skin of the crawler is placed. The brownish black cyst is nearly round, legless, with large spiracular openings, and mouthparts. The second molt occurs about a month later. Emergent adult females have legs, but mouthparts are lacking or nonfunctional. Immediately after emerging from the cyst, the adult female integument is very flexible, and the legs and antennae are telescoped inside the body ( Fig. 9 ). The adult female pushes the shed skin of the crawler aside and squeezes through the small opening of the gall. Adult females settle under bark flakes on the main branches or trunk of the host, produce an oval flattened pad of wax that is covered by white wax threads, and lay 150–500 lemon yellow eggs. There is no discussion of males in any stage in Parr (1939) but Morrison (1939) discussed the existence of second and third-instar males when he described the species.

It is not entirely clear that this species has the same life history as that suggested by Parr (1939) in other parts of its distribution. We have examined the dates of collection of all adult females deposited in the U. S. National Museum scale-insect collection in Beltsville, Maryland, and find specimens from every month of the year except August ( Table 4 ). We excluded any specimens that appeared to have been mummies when they were collected.

As indicated above, Parr (1939) suggested that the legs and antennae are telescoped inside the body while pushing through the hole in the host. It appears to us that they are external but are in pockets in the derm. In either case, they are folded in specific ways. Each antenna is oriented posteriorly and is folded at segment three with the distal segments resting under or within the much longer two basal segments. The third segment is bent when the antenna is folded ( Figure 9 ). Each leg is oriented with the claw and tarsus anterior of the tibia and femur. The trochanter is bent in the middle and is attached to the coxa which lies under the rest of the leg (claw, tarsus, tibia, femur and part of the trochanter) ( Figure 9 ). There is a definite division in the middle of the trochanter in fully extended legs, which suggests it is folded during emergence.

Florida distribution. We have examined the specimens reported by Morrison (1939) from Florida that are deposited in the USNM. They are either cysts or first instars and we are unable to verify their identity without examination of associated adult females or third-instar males. The cysts of M. gallicolus are different from all other species treated by Morrison in 1939 based on the protrusion on the dorsum used by the adult female and third-instar male to escape the gall, but we suspect that M. krystalae has the same characteristics. Because identifiable specimens of M. gallicolus have not been collected in Florida, we suspect that the Florida records are actually of M. krystalae .

Distribution outside of Florida. Matsucoccus gallicolus Morrison has been reported from Connecticut, District of Columbia, Georgia, Kentucky, Maine, Maryland, Massachusetts, Missouri, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, Tennessee, and Virginia. We examined a specimen from Alabama and Ray (1982) reported it from South Carolina.

Damage. Parr (1939) did a careful analysis of the effect of the feeding of M. gallicolus on host tissue in Connecticut and Pennsylvania. About two weeks after a crawler begins feeding, a slight yellowing of the twig surface develops around the insect body where it is in contact with the host. Normal epidermal and collenchyma cells outside of the feeding area have heavy walls but those in the area of feeding become thin walled, empty and stop growing. This causes the formation of a depression under the insect and this combined with abnormal growth of the epidermal and collenchyma cells surrounding the body of the crawler causes gall formation. By the end of June, the cells under the insect have lignified and this degradation continues until late August when twig death may occur. On pitch pine an infestation of 1.2 insects per square millimeter will cause twig death by the middle or end of July but an infestation of 0.5 insects per square millimeter will cause death of the twig by late August or September. Parr was able to demonstrate that the saliva from the feeding insect was the source of gall induction by the plant.

According to Aughanbaugh (1949) a quarter acre plot was set up in a pitch pine ( Pinus rigida Mill. ) plantation in Pond Bank, Pennsylvania in 1931. At the time the trees seemed healthy containing about 40 cubic feet of wood per acre. The following table is a synopsis of the tables presented by Aughanbaugh (1949) of the damage sustained by trees in the plot for the next several years ( Table 5 ).

Aughanbaugh (1949) suggested that the annual increment accumulated in 1942 of trees at the early age of 23 years demonstrated the serious damage sustained by the trees. Only 652 trees were alive in 1949 (48%) and it seemed doubtful that they would ever attain timber size. Damage can be recognized by trees with dead leaders or branches as the season progresses.

Figures

Figure 9. Matsucoccus gallicolus Morrison. Adult female. Prince Georges Co., Beltsville, Maryland, September 23, 1946, on Pinus sp., Hopkins No., 34109. A) Antenna. B) Thoracic spiracle. C) Short ventral filamentous seta. D) Long ventral filamentous seta. E) Hind tibia, tarsus, claw. F) Abdominal spiracle. G) Multilocular pore. H) Dorsal filamentous seta. I) Cicatrix. J) Bilocular tubular ducts. K) Middle leg folded after emergence through the exit hole in the gall, L–M) Antennae at two stages of elongation after emergence through the exit hole in the gall.

Figure 10. Matsucoccus gallicolus Morrison. Third-instar male. Cooper River, Charleston, South Carolina, April 4, 1909, on Pinus taeda, S.G. Sanders. A) Apical four antennal segments. B) short filamentous seta. C) Thoracic spiracle. D) Hind tibia, tarsus, and claw. E) 1st abdominal spiracle. F) Long filamentous seta. G) 6th abdominal spiracle. H) Bilocular tubular ducts. I) Short dorsal filamentous seta.