SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fd87b101f530dd9a4ef3f7eb172112494239f3abddcb387f917bfecbfad094e' 
  AND token = 'fq9CWkTqQhqHBhH4J1yV11swaKavynpXqJfViLTuEDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}