Crustaceans body only was ~2’ long, claw was an additional 20”

=shelled creatures; “the insects of the sea” ! ~ 4’ long total

some crustaceans are quite colorful; blue, red, ~67,000 species orange, yellow

eg: lobsters, crayfish, shrimp, crabs, water fleas, many are bioluminescent copepods, barnacles, pill bugs, etc

A. crustaceans are mostly aquatic, the great majority vary in size from microscopic (<0.1 mm) to 12’ are marine some crustaceans live for several decades; some inhabit most waters of the earth: ocean , arctic , freshwaters, molt throughout life high mountain creeks and lakes thermal springs, brine waters so continuous increase in size 1. many are benthic

eg. crayfish & freshwater shrimp eg. especially the larger crustaceans; shrimp and

crabs largest crustaceans in freshwaters

eg. also isopods, amphipods some up to 2’ and weigh 9 lbs

e. Ostracoda (=seed shrimp) a river shrimp, Macrobrachium jamaicense, was

collected from Devils River, Tx: body was 10.5” common in freshwater and marine habitats long, 3’ long including antennae, 3 lbs

mainly benthic animals that inhabit all types of eg largest (longest) is giant Japanese crab substrates in standing and running water

! up to 12’ from end of claws to tail and a weight of a few actively swim just above the substrate 40 lbs (20 kg)

generally use their antennae to move Lobsters may be the longest lived Crustaceans enclosed in bivalve carapace that completely covers one was collected that weighed 35 lbs the entire animal

was estimated to be 50 yrs old; Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 1 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 2

their shells are so strong that they fossilize well found most abundantly in oceans but also common in freshwaters important to paleontolotists in dating sediment may be the most abundant animals on the planet (65,000 fossil species vs 13,000 living species) feed in a variety of ways: scraping food from hard generally feed on bacteria, fungi, algae and detritus surfaces, filtering articles from the water, seizing and biting prey viable eggs have been collected from dried ponds and revived after 20 years extremely important food source for marine fish

some crustaceans construct tubes in sediment, majority of the diet of commercial fish is wood and rock copepods

some are important vectors for diseases such as eg. boring isopods can destroy wooden pilings in less guinea worm than 2 yrs

eg. Water Fleas (=Cladocerans) some isopods can tunnel through limestone rock

cladocera are most abundant in permanent some have been known to burrow through the freshwater ponds & lakes, among marginal insulation of undersea cables shorting them vegetation out

! important part of freshwater zooplankton some crustaceans are sessile (=attached) body is enclosed within a bivalve shell called a eg. barnacles common in intertidal areas carapace that covers the thorax and the abdomen but not the head 2. many small are at the base of aquatic food chains part of zooplankton large eyes – looks like a single eye but is actually 2 compound eyes that are fused together

eg. Copepods very large antennae that are used for locomotion

small, slender, clearly segmented body inside the carapace are 5 or 6 pairs of feet used to

filter the water for food large pair of antennae used for movement

female carries her eggs around in a brood pouch feathery legs to filter food enclosed in carapace

eggs hatch and young swim free – direct development Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 3 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 4 only animals that flourish in the Great Salt Lake of eg. Krill (Euphasids) Utah and other hypersaline environments

small shrimp-like animals extremely abundant in their eggs can persist in dry salty lakebeds marine plankton today they are cultured extensively as fish food or as 3 often occur in swarms up to 30,000 individuals/m novelties; “sea monkeys”

a major part of the diet of whales, seals, penguins and C. while the vast majority of crustaceans are aquatic, cephalopods among others some groups are semiaquatic or terrestrial

eg. whales eat 2-3 tons of krill per meal eg. land crabs burrow above tide line into the water table

eg. freshwater zooplankton: can survive days out of water

esp. water fleas, copepods, seed shrimp eg. pill bugs & sow bugs (isopods)

B. certain specialized crustaceans are the dominant isopods are the only group of crustaceans with truly animals in highly saline or alkaline environments terrestrial representatives or in temporary waters such as playas have very delicate gill-like respiratory organs that eg. fairy shrimp, tadpole shrimp, clam shrimp must be kept moist

generally inhabit temporary pools, ponds and playas found in damp places under stones and logs

and are generally completely absent from able to roll up for protection (=rolly pollys) permanent bodies of water young develop in brood pouch feed mainly on algae, bacteria, protists and microscopic animals some salt water relatives are found along coasts and live in seaweed, along rocks and algae typically appear in the spring and disappear in late summer or autumn as habitat dries some bore into wood causing destruction of pilings and warves to survive most produce very drought resistant eggs that can survive dried or frozen for years in eg. beach fleas or sand hoppers (amphipods) lake beds some are almost terrestrial; found crawling around on eg brine shrimp (Artemia) piers and jetties

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 5 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 6

Crustacean Body Form most appendages are biramous the most ancient crustaceans resembled some kind of aquatic centipede; lots of segments, each with a they branch like a “wishbone”; one of the pair of appendages branches usually has a gill attached at its base only one small group of these kinds of crustaceans remain today most primitive species had long segmented body with similar segments and similar appendages in most crustaceans today, the body is usually divided into a cephalothorax, abdomen and tail over time, great variety of body types arose cephalothorax appendages modified for a variety of uses: sensory often have carapace extending over the sides of feeding defense the animal walking swimming in some groups carapace forms clamshell like valves that reproduction encloses the whole body respiration

in others the carapace covers cephalothorax but not abdomen lots of variation in appendages between groups abdomen eg in decapods (crayfish, crabs, lobsters, etc):

1st 2 pair ! antennae with chemoreceptors segmentation is most apparent in the abdomen next 5 pr (3-8) ! feeding appendages; including abdomen usually with pairs of jointed mandible, maxilla and maxillipeds

appendages on most segments next 5 (9-13) ! walking legs including cheliped and gills Movement next 5 (14-18) ! called swimmerets; used to carry eggs and as copulatory organ generally have many pairs of appendages

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 7 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 8 last (19) ! uropod = swim fin live in solitary burrows

most crustaceans can cast off legs or pinchers and eyes are stalked and constantly watch for prey

regrow them some are suspension feeders voluntary (striated) muscle tissue arranged in eg. barnacles sit upside down in shell and use antagonistic groups legs to strain water for food

eg. flexors & extensors some are scavengers

similar to vertebrates eg. isopods, amphipods

Feeding & Digestion crustaceans have a well developed digestive system:

cardiac stomach with gastric mill for grinding use jaw-like mandibles as main feeding

structures gastric mill has hardened “teeth”

also maxillae and maxillipeds pyloric stomach for sorting

great variation in feeding types: digestive gland secretes digestive enzymes

many are predators Respiration eg. crabs use large claws used to break open shells to feed in small crustacea: no special organs eg. mantis shrimp

is an ambush predator, extremely carnivorous and ! exchange across body surface aggressive in larger crustacea: respiration usually by feathery called “split thumb” in Bermuda and West Indies gills front end looks like praying mantis on bases of walking legs has “jackknife claws”

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 9 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 10

in some sides of carapace form gill chambers at base of antennae that enclose gills saclike; opens to surface by pore have an appendage called a “bailer” that creates a water current across gills take in sand grains which trigger hair cells to provide info on orientation Circulation 6. hearing: communication by sound open circulatory system many crustaceans make underwater noises to most crustaceans have some kind of blood pigment to communicate better distribute oxygen to tissues eg. pistol crabs snap claws together producing sound most: hemocyanin ! bluish pigment with Copper like pulling a cork from a bottle

others: hemoglobin ! red pigment with Iron eg. one species of mantis shrimp makes a vigorous rasping noise by rubbing uropods against some: no pigments underside of telson

eg. Florida spiny crab produces sound like moist Sense Organs fingers rubbing against a window pane sense organs are well developed in crustaceans some crabs have striae or ridges on inner side of chelae that they rub against tubercles on 1. most have compound eyes and simple eyes carapace

some crabs have tympanic membranes on their 2. chemoreceptors (taste) on mouthparts, st 1 leg segments to pick up these sound 3. crustaceans uniquely have 2 pairs of antennae vibrations

4. tactile hairs and spines spread over body sound is used for warning, to frighten enemies, mating rituals, etc 5. statocysts for orientation

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 11 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 12 7. Light emitting organs & communication by Excretion light nitrogen wastes are excreted through skin (if no gills) many crustaceans have light emitting organs (=photophores) that use luciferase to or through gills & antennal glands (or produce light maxillary/green gland)

many crustaceans give off rich blue sparks of light antennal glands also used to regulate water & when disturbed salts

+ eg. some ostracods and a few copepods, even some (K & Ca conserved; SO4 & Mg excreted) freshwater decapods [no malpighian tubules] krill have light organs with lens and reflector to focus and intensify the light beam Reproduction

many pelagic crustacea flash brilliantly during most are separate sexed (dioecious) mating swarms but a few are hermaphrodites including barnacles Endocrine System

female can only mate after final molt hormones help control:

develops large “apron” for carrying eggs molting

copulation: male delivers sperm packet to body coloration ! chromatophores receptacle using modified swimmerets

heart rate a few groups reproduce parthenogenetically

sexual development eg. brachiopods, ostracods, isopods and a few crayfish

blood sugar levels males are rare or unknown

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 13 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 14

eggs are generally released into the water b. mutualistic interactions some retain their eggs until they hatch in brood eg. cleaner shrimp remove skin parasites from fish pouches c. a diverse variety of crustaceans have become eg. Most crabs and shrimp parasitic in some crustacea such as crayfish, development is eg. Fish Lice direct with no larval stage parasites on marine and freshwater fish but most crustaceans produce a variety of distinctive have flattened bodies, compound eyes and maxillae larval forms as the animal develops modified into suckers to attach to the sides of fish many marine crustaeans begin with a characteristic mouth borne on a long tube or piercing organ used to obtain food; blood and body fluids of host larval form after feeding on host the parasite detaches and drifts = nauplius larva downstream 2 pr antennae 3 prs appendages many species can tolerate both fresh and salt waters 1 pr mandibles eg. Tongue Worms

then zoea larva or some other larva distinctive for so unlike other crustaceans that until recently they were the specific group classified in their own phylum, pentastomida

wormlike; 2-13 cm long; >70 sp, 4 fossil genera Symbioses 4 clawlike appendages at anterior end a. numerous commensal relationships with other mouth with protuberance invertebrates no resp, circ or excretory organs eg. many bivalves harbor commensal crabs within their shells parasites in lungs of carnivourous vertebrates esp reptiles and some birds eg. crabs and shrimp also live inside sponges, worm tubes, etc few human infections

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 15 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 16 ! both male and female resemble mature female intermediate host is vertebrate prey of final host bearing eggs: physically and behaviorally larvae live in blood

eg. probably the most bizzare of all parasitic animals is Sacculina

Sacculina is a highly modified barnacle that has become a parasite of crabs

female cypris larva attaches to a crab and injects a mass of eggs

these cells migrate to intestine of host and develop rootlike growths that permeate the hosts body

develops an extensive system of branches extending into every appendage

a saclike growth appears under the crabs abdomen where eggs and sperm form (Sacculina is a hermaphrodite)

the crabs metabolism is completely altered:

the cells of the parasite multiply and differentiate into a reproductive form which produce an egg mass in the female hosts apron

the host protects, ventilates and grooms the egg mass as if it were her own

if crab is a male:

body assumes shape of a female reduced length of some segments broadening of abdomen testes reduced or converted to ovaries

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 17 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 18

Classification of Crustacea Ecological Role of Crustaceans

6 Classes: many examples have already been cited

Class Remipedia (10 sp.) crustaceans feed a vast number of other animals in Class Cephalocarida (9 sp.) the oceans and in freshwaters

Class Branchipoda (10,000 sp.) small planktonic crustaceans such as copepods, water fleas, fairy shrimp, brine shrimp) ostracods and krill are essential links between

Class Maxillipoda (10,000 sp.) producers and larger consumers in aquatic food copepods, barnacles, fish lice and tongue worms webs

Class Ostracoda (13,000 sp.) krill and copepods are extremely abundant in the seed shrimp worlds oceans Class Malacostraca (20,000 sp.) sand fleas, shrimp, crabs, lobster, wood lice may be the animals with the greatest biomass on

the planet

[short descriptions of these major groups can be found on pp 24 & ff] their numerous symbioses help to control populations

of other animals

without crustaceans, animal populations in aquatic ecosystems would collapse

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 19 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 20 Economic Importance of Louisiana produces 70-90% of all commercial crayfish, most of it from aquaculture Crustaceans

recent (2007) annual harvest of ~55,000 tons many are at the base of aquatic food chains part of zooplankton Krill are now being harvested for human consumption around the Antarctic 1. as food

eg. crab, lobster, crayfish, shrimp can harvest 12 tons/hour

more than 10 million tons of crustaceans are but they are difficult to process harvested for food each year (2007) 2. bait ! mostly shrimp, crab, lobsters and prawns crayfish are commonly sold and used as bait either live or only the tail meat the heyday of lobster fishing was in the 1890’s: sometimes causes problems with bioinvasions

1892 yield was 24 M lbs of lobster; 3. pets 25 pounders were common crayfish are kept as pets in freshwater aquaria 80% of all crustaceans are harvested in Asia, mainly China land crabs are often sold in pet stores

some crab are harvested by breaking off claws 4. many crustaceans are serious pests and throwing rest back a. cause crop destruction crayfish (crawfish) are commonly eaten in the southern US and in other countries eg. rice crabs in China and India eat rice; burrows may drain rice fields destroying crops

eg. crayfish destroy young cotton plants Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 21 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 22

Short Descriptions of the Major b. boring & fouling organisms Groups of Crustacea borers destroy warves & docks and wooden hulled boats Class Remipedia

very primitive characteristics undermine sea walls and bore into stone ! resembles a centipede in general body form but with destroy underwater cables biramous legs

very poorly known ! all known species are from underwater adhere to ships reduce efficiency and increase caves hull decay Class Cephalocarida

eg. barnacles occur along the coasts of the United States, in the West Indies and Japan 5. Many Crustaceans are endo- and ectoparasites on other organisms 2-3 mm long

live in bottom sediment from intertidal zone to 300 m eg. many kinds of copepods

eg. Sacculina also thought to be very primitive

6. some act as intermediate hosts for human Class Malacostraca parasites largest crustacean class eg. Guinea worm larva is in copepods; swallowed in contaminated water extremely diverse grow in lymphatic system up to 3’ long appendages on both thorax and abdomen female produces blister like lesions on lower extremeties to lay eggs in water Isopoda

eg. fish tapeworm only group of crustaceans with truly terrestrial larva in Cyclops and Diaptomus representatives: sow bugs, pill bugs eaten by fish humans eat uncooked fish

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 23 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 24 most species are either marine or terrestrial, only a few Amphipods, Sand Fleas or Scuds (=Amphipoda) (5%) are freshwater species a mainly marine group with some freshwater species mainly found crawling on the substrate or under rocks and submerged plants in small lakes and streams strongly compressed laterally, no carapace

a few cave adapted forms occur in subterranean abdomen not sharply separated from cephalothorax waters compound eyes lie flat on the sides of the head rather than commonly dorsoventrally flattened, segmented, with a on stalks reduced cephalothorax generally much more active at night than during daytime most are less than .5”, the largest is over 12” long (Bathynomus – a deep water species) amphipods are voracious feeders

seldom found in open water omnivorous scavengers

isopods are mainly scavengers feed on all kinds of plant and animal matter

dioecious with no larval stage a few are parasites

eg. pill bugs & sow bugs (isopods) like decapods, the females brood eggs and young in a ventral brood chamber only truly terrestrial crustaceans eg. beach fleas or sand hoppers (amphipods) have very delicate gill-like respiratory organs that must be kept moist found in both freshwaters and marine habitats

found in damp places under stones and logs some are almost terrestrial; found crawling around on piers and jetties able to roll up for protection (=rolly pollys) Decapoda young develop in brood pouch best studied group of crustacea some salt water relatives are found along coasts and live in seaweed, along rocks and algae ~10,000 species

some bore into wood causing destruction of pilings most larger crustaceans; shrimp, crayfish & true crabs and warves vast majority are marine, some found in freshwaters

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 25 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 26

5 pairs of walking legs one was collected that weighed 35 lbs was mainly benthic: in and on the sediment estimated to be 50 yrs old; body only was 2’ long, claw was an additional 20” ! ~ 4’ long lots of specialized legs total

crabs use large claws used to break open shells to feed the heyday of lobster fishing was in the 1890’s:

fiddler crab uses largest claw for social interactions 1892 yield was 24 M lbs of lobster

only uses small claw for scavenging food from 25 pounders were common sand eg. crayfish & freshwater shrimp others are filter feeders, herbivores or scavengers freshwater decapods most crab and shrimp carry eggs or brood their young largest crustaceans in freshwaters eg. cleaner shrimp remove skin parasites from fish some up to 2’ and weigh 9 lbs eg. land crabs burrow above tide line into the water table a river shrimp, Macrobrachium jamaicense, was can survive days out of water collected from Devils River, Tx: body was 10.5” long, 3’ long including antennae, 3 lbs eg. mantis shrimp Krill (Euphasids) is an ambush predator, extremely carnivorous and aggressive small shrimp-like animals extremely abundant in marine plankton called “split thumb” in Bermuda and West Indies 3 often occur in swarms up to 30,000 individuals/m front end looks like praying mantis a major part of the diet of whales, seals, penguins and has “jackknife claws” cephalopods among others

live in solitary burrows eg. whales eat 2-3 tons of krill per meal

eyes are stalked and constantly watch for prey Class Branchiopoda

eg. Lobster “breath through their feet”

Lobsters may be the longest lived Crustaceans Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 27 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 28 ! feathery gills at base of walking legs large eyes – looks like a single eye but is actually 2 the most characteristic crustaceans of freshwaters compound eyes that are fused together

most are exclusively freshwater forms very large antennae that are used for locomotion

some in brines, only very few marine species inside the carapace are 5 or 6 pairs of feet used to filter the water for food eg. fairy shrimp, tadpole shrimp, clam shrimp, water fleas female carries her eggs around in a brood pouch enclosed feed mainly on algae, bacteria, protists and microscopic animals in carapace

except for the water fleas, the branchipoda generally inhabit eggs hatch and young swim free – direct development temporary pools, ponds and playas Fairy Shrimp (=Anostraca) and are generally completely absent from permanent bodies of water common but seldom seen unless pursued

typically appear in the spring and disappear in late summer stalked compound eyes or autumn as habitat dries no carapace to survive most produce very drought resistant eggs that can survive dried or frozen for years in some grow up to an inch lake beds graceful movements, often transparent the eggs of most hatch into nauplius larvae use legs to swim upsidedown Water Fleas (=Cladocerans) eg brine shrimp (Artemia) cladocera are most abundant in permanent freshwaters only animals that flourish in the Great Salt Lake of ! important part of freshwater zooplankton Utah and other hypersaline environments

cladocera are most abundant among vegetation at margins their eggs can persist in dry salty lakebeds of ponds and lakes today they are cultured extensively as fish food body is not obviously segmented Tadpole Shrimp body is enclosed within a bivalve shell called a carapace that covers the thorax and the abdomen but not the large shield-like carapace covering most of the body head Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 29 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 30

look somewhat like tiny horseshoe crabs difficult to study and identify ! usually requires dissection

at end of abdomen are two long filamentous extensions many species are parthenogenetic

Clam Shrimp viable eggs have been collected from dried ponds and revived after 20 years laterally compressed Class Maxillipoda enclosed within a carapace of 2 valves to resemble a small clam Copepoda

Class Ostracoda (=seed shrimp) small, lack carapace

resembles clams and clam shrimp but much smaller (usually slender, clearly segmented body <1mm) large pair of antennae used for movement common in freshwater and marine habitats feathery legs to filter food mainly benthic animals that inhabit all types of substrates in standing and running water found most abundantly in oceans but also common in freshwaters important interstitial fauna common as plankton, benthos, interstitial fauna a few actively swim just above the substrate also many parasitic species generally use their antennae to move feed in a variety of ways: scraping food from hard enclosed in bivalve carapace that completely covers surfaces, filtering articles from the water, seizing and the entire animal biting prey

their shells are so strong that they fossilize well may be the most abundant animals on the planet

important to paleontolotists in dating sediment extremely important food source for marine fish

(65,000 fossil species vs 13,000 living species) majority of the diet of commercial fish is copepods

nearly all traces of segmentation are gone some are important vectors for diseases such as guinea worm generally feed on bacteria, fungi, algae and detritus Barnacles (=Cirripedia)

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 31 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 32 they don’t feed and die after inseminating the sessile: secrete shell of several calcium plates in which female they live barnacles are preyed on especially by starfish and snails considered a kind of mollusk until 1830 some in symbiosis with humpbacks and other whales but once they were discovered to produce a nauplius larva it was clear they were a kind of crustacean stick on skin; esp head, flippers and flukes

there are 2 main kinds of barnacles: appear to cause little damage except for some species that seem to burrow into the skin but don’t seem some with stalk = goose barnacles to cause serious inflammation

some without = acorn barnacles feed on scraps produced by whale feeding

eggs hatch into motile, nauplius larvae then a cypris larva some are parasitic

after swimming a short time the larva secretes a includes one of the most bizarre parasites of all, strong polysaccharide cement from its antennae Sacculina: and attaches to the substrate Sacculina is a highly modified barnacle that has ! the strongest adhesive known become a parasite of crabs

adults secrete chemicals that attract the larvae to settle female cypris larva attaches to a crab and injects near them to facilitate reproduction a mass of eggs

the carapace develops into a mantle that secretes these cells migrate to intestine of host and calcareous plates develop rootlike growths that permeate the hosts body legs develop in feathery cirri for filtering water develops an extensive system of branches extending animal sits up-side-down in shell and extends legs to filter into every appendage feed a saclike growth appears under the crabs abdomen almost all are hermaphrodites yet they cross fertilize with where eggs and sperm form (Sacculina is a internal fertilization hermaphrodite)

a few species are dioecious with the dwarf males the crabs metabolism is completely altered: attached to the female

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 33 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 34

the cells of the parasite multiply and differentiate after feeding on host the parasite detaches and drifts into a reproductive form which produce an downstream egg mass in the female hosts apron many species can tolerate both fresh and salt waters the host protects, ventilates and grooms the egg mass as if it were her own Tongue Worms

if crab is a male: so unlike other crustaceans that until recently they were classified in their own phylum, pentastomida body assumes shape of a female reduced length of some segments wormlike; 2-13 cm long; >70 sp, 4 fossil genera broadening of abdomen testes reduced or converted to ovaries 4 clawlike appendages at anterior end

! both male and female resemble mature female mouth with protuberance bearing eggs: physically and behaviorally body covered by chitinous cuticle, periodically molted barnacles are one of the most important “fouling” organisms on ocean going ships single digestive tract

! reduce speed up to 50% no resp, circ or excretory organs ! increase duration of voyage ! increase fuel consumption parasites in lungs of carnivourous vertebrates esp reptiles ! increase wear and tear on engine and some birds

all this translates into millions of dollars lost in few human infections ocean transport intermediate host is vertebrate prey of final host in Chile a large 9” barnacle is an important food source that larvae live in blood is used in soups and chowders

Fish Lice

parasites on marine and freshwater fish

have flattened bodies, compound eyes and maxillae modified into suckers to attach to the sides of fish

mouth borne on a long tube or piercing organ used to obtain food; blood and body fluids of host

Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 35 Animals: Arthropoda - Crustacea; Ziser Lecture Notes, , 2012.10 36